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Fit for September: Must Haves

FitSugar — Tue, 02 Sep 2008 05:30:00 -0700

Now that Labor Day has passed us by, it's time to kiss the dog days of Summer good-bye. Just because you're putting away your bathing suit does not mean that you should also put away your motivation to stay fit. Being healthy is much more than looking good on the beach. Use my September Must Haves to welcome the first day of Fall, and of the rest of your life.

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Fit For September: Must Haves

FitSugar — Tue, 01 Sep 2009 03:30:36 -0700

Thirty days has September, and with items like these you can make the most of those 30 days! Fall is beginning and it's back-to-school time. Even if you are not headed to class, these five buys will help you be fit for September.

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Fit For September: Must Haves

FitSugar — Tue, 04 Sep 2007 04:00:00 -0700

"Thirty days has September" and with items like these you can make the most of those thirty days! Fall is beginning and it's back to school time! Even if you are not headed to class these five buys will help you be fit in and for September.

To read about these must haves just read more

What better way to head back to school than on a bike! Jorg and Olif have just introduced their latest city bike - the Scout ($495). Cruise around town in style on the limited edition red bike.
When tooling about town on your retro bicycle, you are going to want to protect your laptop as well as your back, by carrying all your gear in the Kata Ergo-Tech Sensitivity V backpack ($85) by Kata. Not only does it look like something James Bond would carry, but this pack will not double cross your shoulders or back since its ergonomic design is body friendly.
Because it is (or will be by the end of the month hopefully) getting cooler outside, you're going to need a hoodie and I am loving the Practice Hoodie ($69) by Athleta. The feminine pattern combined with the three quarter sleeves give it a girly, yet sporty look.
Fall just wouldn't be fall without an apple for your teacher, but this September I would go with apple juice instead, and the cloudier the better. Recent studies indicate the cloudier the apple juice the more antioxidants it contains. So drink up!
You should also start thinking about moving some of your workouts inside and if you are a cardio junkie you need to also start thinking about adding weight training into your routine. I say this because the new exercise guidelines suggest adding 2 days of strength training a week. Look for circuit training group classes where you can get your heart rate up while you build some muscle. Or create you own!

Gear Review: Hatha Power Pants by Lucy

FitSugar — Mon, 21 Sep 2009 10:00:20 -0700

Occasionally, I come across a pair of yoga pant that I just never want to take off and lately Hatha Power Pant ($88) by Lucy have become my second skin. Made from Lucy's powermax fabric, a mixture of nylon and lycra, these pants are designed to manage the moisture that can accompany a sweaty yoga class. Wicking fabrics are important for yoga too. The low-rise waistband is super comfy and placement of the seams makes the pants extremely flattering. My husband comments how much he likes these pants every time he sees me in them, which these days is frequently. In honor of National Yoga Month, Lucy is donating five percent of the sales from the Hatha Power Pant to Off the Mat, Into the World. This yoga inspired non-profit organization, created by activist yogi Seane Corn, seeks to change the world by inspiring yoga students to become involved in their local community and the global community to create positive change in the world. Lucy is so dedicated to this organization that they are offering free shipping on the Hatha Power Pant through the end of September. If you're looking for a new pair of luxury yoga pants, good for Pilates and weight training as well, try the Hatha Power Pant. They might just get you onto the mat, and you will probably wear them out in the world.

A couple more notes on the pants: They fit well and might run a bit large, so if you're between sizes I would go for the smaller size. These pants wash up well, just line dry them to protect their wicking qualities.

Itchy Legs and Running

FitSugar — Wed, 09 Sep 2009 05:50:57 -0700

It's a beautiful September day. There's a cool breeze blowing, not a cloud in the sky, and it's inspired you to lace up your sneaks after taking a break from running all Summer. A few minutes into it, you start to experience an itchy sensation all over your legs, and it's so overwhelming that you have to stop running to scratch. What gives?

The reason our skin itches is because of what's happening inside our bodies. The millions of tiny capillaries and arteries in your muscles begin to expand rapidly as your heart rate increases, and blood is flowing quicker. If you're a fit person, your capillaries stay open to allow for maximum blood passage. If you're out of shape, your capillaries tend to collapse and don't allow as much blood to pass through. When your capillaries expand, they cause adjacent nerves to send messages to the brain, which reads the sensation as itching. I hate to say it, but this is the price some people pay for falling off the exercise wagon. To prevent itchy legs, keep up with your regular exercise routine.

FitSugar Roundup

FitSugar — Sat, 05 Sep 2009 05:50:01 -0700

Alicia Silverstone helps the planet by gardening naked.
You can satisfy your sweet tooth with snacks under 200 calories.
Tell me, what kind of stomach do you have?
Is diet soda healthier than regular? Read and learn.
Check out my September must haves. They'll help you stay fit as the seasons change.
With so many ways to top a bagel, how do you choose?
Drinking alcohol could motivate you to exercise.
Tone your shoulders with these simple moves.
Can you name the yoga pose?

Colon and rectal cancers

FitSugar — Wed, 08 Oct 2008 17:35:05 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Risk Factors
Dietary Factors
Prevention
Diagnosis
Staging
Prognosis
Surgery
Medications
Radiation Treatment
Follow-up Testing
Treatment for Metastasized ...
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approval

In September 2006, the Food and Drug Administration approved panitumumab (Vectibix) for the treatment of patients with colorectal cancer that has spread to other parts of the body following chemotherapy. Like cetuximab (Ertibux), panitumumab targets the epidermal growth factor receptor (EGFR) on cancer cells. Panitumumab is the first new colorectal cancer drug approved since 2004. The FDA granted accelerated approval to panitumumab based on a clinical trial of patients with metastatic cancer. The average time to disease progression or death was 96 days in patients treated with panitumumab compared to 60 days in patients who received standard care.

Diet and Colorectal Cancer Recurrence

Evidence indicates that diet plays a role in colorectal cancer prevention. Now, a 2007 study in the Journal of the American Medical Association (JAMA) suggests that dietary factors also affect the risk of cancer recurrence. Patients with stage III colorectal cancer who ate lots of red meat, refined grains, and sweets had a higher risk of cancer recurrence and death than patients whose diets were high in fruits and vegetables, poultry, and fish.

Folic Acid No Good for Prevention?

Many experts have long believed that folic acid supplements may help protect against colorectal cancer. But according to a 2007 JAMA study, high-dose folic acid supplements may not prevent colorectal cancer and may actually increase the risk for adenomatous polyp formation. Adenomatous polyps are benign colorectal tumors that can potentially become cancerous. In the study, patients who took folic acid supplements had a greater risk of developing new, more numerous, and larger adenomatous polyps than patients who did not take the supplements.

NSAIDS Not Recommended for Colorectal Cancer Prevention

In March 2007, the U.S. Preventive Services Task Force (USPSTF) recommended against the routine use of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) to prevent colorectal cancer in people who are at average risk for this disease. Several recent studies have indicated that aspirin, and NSAIDs such as celecoxib (Celebrex), can help prevent colorectal cancer. But the USPSTF notes that the risks of these drugs outweigh the benefits. Long-term daily use of NSAIDs increases the risk for gastrointestinal bleeding, kidney function problems, and heart attack and stroke.

Introduction

Cancers of the colon and rectum, often referred to collectively as colorectal cancer, are life-threatening tumors that develop in the large intestine.

More than 80% of colorectal tumors evolve from adenomatous polyps. These gland-like growths develop on the mucous membrane that lines the large intestine. They are usually either:

Tubular polyps, which protrude mushroom-like
Villous adenomas, which are flat and spreading and are more apt to become malignant (cancerous)

Polyps are very common and almost always benign. Their numbers increase with age. Polyps are found in about 25% of people by age 50, and 50% of people by age 75. Fewer than 1% of polyps under 1 centimeter (slightly less than half an inch) become cancerous. About 10% of larger polyps become cancerous within 10 years, and about 25% of these larger polyps become cancerous after 20 years. Certain inherited polyps can become cancerous more rapidly.

Digestion takes place in the gastrointestinal (GI) tract, essentially a long tube that extends from the mouth to the anus. It is a complex organ system that first carries food from the mouth down the esophagus to the stomach. Food then travels through the small and large intestines before being excreted through the rectum and out the anus.

The esophagus, stomach, large and small intestine -- aided by the liver, gallbladder, and pancreas -- convert the nutritive components of food into energy and break down the non-nutritive components into waste to be excreted.

The esophagus is a narrow muscular tube, about 9 1/2 inches long that begins below the tongue and ends at the stomach.

In the stomach, acids and stomach motion break food down into particles small enough so that the small intestine can absorb nutrients.

Click the icon to see an image of stomach anatomy.

The small intestine, despite its name, is the longest part of the gastrointestinal tract, extending for about 20 feet. Food passes from the stomach through its three parts: first the duodenum, then the jejunum, and finally the ileum. Most of the digestive process occurs in the small intestine.

Click the icon to see an image of small intestine anatomy.

Undigested material, such as plant fiber, is passed next to the large intestine, mostly in liquid form. The large intestine is wider than the small intestine but only about 6 feet long. It is the final portion of the digestive tract and includes the cecum, the appendix, the colon, and the rectum, which extends to the anus.

Cecum and Appendix. The cecum and the appendix are located in the lower-right quadrant of the abdomen.

Colon. The colon absorbs excess water and salts into the blood. The remaining waste matter is converted to feces through bacterial action. The colon is divided into four major sections.

Click the icon to see an image of large intestine anatomy.

The first section, the ascending colon, extends upward from the cecum on the right side of the abdomen.
The second section, the transverse colon, crosses the upper abdomen to the left side.
The third section extends downward on the left side of the abdomen toward the pelvis and is called the descending colon.
The final section is the sigmoid colon.

Rectum and Anus. Feces are stored in the descending and sigmoid colon until they are passed through the rectum and anus. The rectum extends through the pelvis from the end of the sigmoid colon to the anus.

Causes

In most cases of colon or rectal cancers, the cause or causes are unknown. Defects in genes that normally protect against cancer play the major role in causing polyp cells to continuously spread and become cancerous. Some of these cases are caused by inherited genetic defects, and such patients usually have family histories of colorectal cancer. Most of the genetic mutations involved in colon cancers, however, appear to arise spontaneously (no strong family history) rather than being inherited. In such cases, environmental or other factors trigger genetic changes in the intestine that lead to cancer.

About 6% of cases of colon cancer are due to inherited factors.

APC Gene and Familial Adenomatous Polyposis (FAP). When the adenomatous polyposis coli (APC) gene is normal, it helps suppress tumor growth. In its defective form, it permits high levels of the protein beta-catenin to accumulate, which accelerates cell growth leading to polyps. Various genetic mutations that affect the APC gene directly or indirectly have been identified:

Familial adenomatous polyposis (FAP) is a rare and serious disorder in which the patient inherits an adenomatous polyposis coli (APC) mutation from either parent. It occurs in about 1 in 8,000 people. During early adulthood, hundreds to thousands of polyps grow in the colon. FAP causes less than 1% of all cases of colorectal cancer, but if untreated, virtually everyone who inherits this condition develops cancer before the age of 40. Many of the deaths attributed to FAP can be prevented with early and aggressive surgical treatment.
Non-inherited mutations of the APC gene have been detected in nearly all patients with spontaneous colon cancers.

Hereditary Nonpolyposis Colorectal Cancer (HNPCC). Hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome, accounts for at least half of colorectal cancers that run in families. (However, only 3% or less of all colorectal cancers are due to this problem). About 50 - 80% of people who inherit the abnormal gene will develop colon cancer. HNPCC tends to develop in the right side of the colon, often in young individuals. (Left-sided cancers can still occur as well.)

People who inherit HNPCC and other defects are prone to other cancers, including uterine and ovarian cancers, as well as cancers of the small intestine and kidney system (very rare). HNPCC is highly associated with genes containing an abnormality called microsatellite instability (MSI), which is a sign of defective DNA repair. Testing tumors for MSI in people with newly diagnosed colon cancer who also have a family history of the disease may prove to be an effective method for identifying patients with hereditary nonpolyposis colorectal cancer. Tests are being developed that can detect the actual HNPCC genetic abnormality (mutation) that was inherited from a father or mother. The two most commonly affected genes are MSH2 and MLH1.

Cyclooxygenases and Prostaglandins. Cyclooxygenase 1 and 2 (COX-1 and COX-2) are enzymes involved in the production of prostaglandins, substances produced by the body that cause inflammation, widen and narrow blood vessels, control muscle contractions, and inhibit hormones that regulate fat metabolism. COX-2, but not COX-1, appears to play a role in the development and spread of colorectal tumors. COX-2 increases the levels of prostaglandin E2 (PGE2), which, in turn, stimulates factors that inhibit apoptosis, the natural process whereby all cells, including cancerous ones, self-destruct. It also activates interleukin-6 (IL-6), a factor in the immune system that is associated with cancer cell invasion.

C-Reactive Protein (CRP). CRP is another indicator of inflammation. In a 2004 study published in the Journal of the American Medical Association, elevated CRP levels predicted the development of colon -- but not rectal -- cancer.

Bile Acid Salts. Deoxycholic acid, which is found in the fat-digesting bile salts released by the gallbladder, appears to have carcinogenic properties. Its effects are now believed to play a role in some cases of colon cancer. Levels of the acid can rise as a result of high-fat diets or certain diseases.

Growth Factors. Chronically higher circulating levels of growth factors, including insulin-like growth factor, have been associated with colorectal cancer.

Inflammatory bowel diseases include Crohn's disease and ulcerative colitis. These chronic disorders cause persistent injuries in the intestinal tract that can, in some cases, produce cancerous changes.

Symptoms

It is possible to have colon or rectal cancer without symptoms. Many patients are free of symptoms until their tumors are quite advanced.

Weight loss and changes in bowel movements are general symptoms for colon cancer, but these symptoms also occur in many other diseases.

Blood in the stools is a common sign of many intestinal cancers. It may appear red if it is fresh or black if it is old. It should be reported to a doctor immediately, even though it is often caused by conditions other than cancer, including:

Hemorrhoids
Minor tears around the rectal or anal areas
Diverticulosis

In addition, stool can change color by:

Eating certain red foods, such as beets or red licorice (red)
Taking iron supplements and medications that have bismuth subsalicylate, most commonly Pepto-Bismol (black)

Nevertheless, blood in the stools is an abnormal finding that should never be ignored. Always report it to your doctor for further advice.

Symptoms of colorectal cancer vary widely depending on the location of the cancer within the large intestine.

Tumors in the Cecum and Ascending Colon (Right Colon). The waste matter in the first portion of the colon is in liquid or semi-liquid form. Tumors that develop here do not change bowel habits or stool formation, but they may cause intermittent or chronic bleeding. Although the stools look normal, patients may develop symptoms of anemia from iron deficiency. Such symptoms include weakness, fatigue, heart palpitations, shortness of breath, and exercise intolerance.

Tumors in the Transverse Colon. As waste material passes across the upper quadrants of the abdomen (the transverse colon), the intestine absorbs water, and the waste matter becomes more solid. In addition to bleeding, tumors here may cause cramps, gas, partial or complete obstruction, and even perforation of the bowel. Anemia can also occur.

Tumors in the Descending Colon and Rectum (Left Colon). When tumors partially block the lower intestine, thin, pencil-shaped stools may form. Bowel habits can change. Tumors in the rectum and lowest part of the intestine can cause pain and a feeling of fullness. Defecation may be painful, or patients may feel the urge to defecate but nothing happens. Bleeding from these locations may be brisk and bright red or maroon, but cancer is often detected before symptoms of chronic anemia develop.

Risk Factors

Colorectal cancer is the third most common cancer in the U.S., with Americans facing a lifetime chance of 5.5 - 6% for this cancer. In 2007, colorectal cancer was expected to cause 153,760 new cases and 52,180 deaths in the United States. About 73% of cancers occur in the colon and 27% in the rectum.

The lifetime risk of cancer of the colon or rectum is 5.9% for men and 5.5% for women.

Colorectal cancer risk increases with age. More than 90% of these cancers occur in people over age 50. The rate of colorectal cancer in patients under 20 years is less than 1 in 100,000 per year. At age 50 about 1 in 2,000 people per year will develop colorectal cancer. After age 65, this rate increases to almost 3 in 1,000.

African-Americans have the highest risk of being diagnosed with, and dying from, colorectal cancer. Among Caucasians, Jews of Eastern European (Ashkenazi) descent have an elevated rate of colorectal cancer. Asian Americans/Pacific Islanders, Hispanics/Latinos, and American Indians/Alaska Natives have a lower risk than Caucasians.

About 20 - 25% of colorectal cancers occur among people with a family history of the disease. (Seventy-five percent of cases are due to other causes.) People who have more than one first-degree relative (sibling or parent) with the disease are especially at high risk. The risk is even higher if the relative was diagnosed with colorectal cancer before the age of 60.

About 5 - 10% of patients with colorectal cancer have an inherited genetic abnormality that causes the disease. Genetic mutations associated with colorectal cancer include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.

The risks for colon cancer are far higher in industrialized nations than less developed countries. A Western lifestyle, being sedentary, smoking, and having excess weight have all been associated with increased risk for colorectal cancer. (However, about 75% of cases occur without a known predisposing factor.)

Dietary Factors. Eating a lot of red meat increases the risk for colorectal cancer. Other types of animal protein (low-fat dairy products, fish, poultry) may decrease the risk of developing polyps and colorectal cancer. Studies on fruits, vegetables, and fiber are mixed. Some evidence suggests that diets very low in fruits and vegetables may increase the risk. In any case, eating a variety of fruits and vegetables should be part of a healthy diet.

A 2007 study in the Journal of the American Medical Association suggested that diet may play a role in colorectal cancer recurrence, as well as prevention. The study evaluated patients with stage III colon cancer who had been treated with surgery and chemotherapy. Patients who ate diets high in red and processed meats, refined grains, and sweets had a higher risk of cancer recurrence and poorer survival than patients whose diets were high in fruits and vegetables, poultry, and fish.

Alcohol and Smoking. Alcohol use and smoking increase the risk for colorectal cancer. Patients who smoke and drink may also be diagnosed with colorectal cancer at a younger age than non-drinkers and non-smokers. Several studies suggest that women who smoke are at especially high risk of developing colorectal cancer.

Obesity. There is a demonstrated link between body mass and colon cancer risk for both men and women. The Centers for Disease Control and Prevention has reported that the risk of colon cancer rises as body mass index increases. Obesity has been associated biologically with higher circulating levels of insulin and a hormone called insulin-like growth factor. Chronically high levels of these substances may increase colorectal cancer risk.

Physical Inactivity. More than 50 studies from around the world suggest that physical activity helps prevent colon cancer. In contrast, exercise does not protect against rectal cancer.

Crohn's disease and ulcerative colitis are chronic afflictions of the large intestine known as inflammatory bowel diseases (IBD). Both have been linked to increased risk for colorectal cancer. (Patients with ulcerative colitis have a higher risk than those with Crohn's disease.) Family histories are helpful in determining risk associated with inflammatory bowel disease. Some studies suggest the following:

Patients with IBD who have a family history of colorectal cancer face up to a five-fold risk of colon cancer themselves.
Individuals without IBD who have relatives who suffered from both IBD and colorectal cancer may face a higher risk for developing colorectal cancer themselves.
Individuals without IBD but with a family history of IBD and no colon cancer most likely face no higher risk for cancer themselves.

Crohn's disease, also called regional enteritis, is a chronic inflammation of the intestines that is usually confined to the terminal portion of the small intestine, the ileum. Ulcerative colitis is a similar inflammation of the colon, or large intestine. These and other inflammatory bowel diseases have been linked with an increased risk of colorectal cancer.

Polyps. Polyps are tissue growths, usually benign, that develop in the color or rectum, most often in patients over 50 years of age. When pathologists examine polyps removed from the colon, they classify them as either hyperplastic or adenomatous. Both types are benign, but some adenomas will become malignant. As a preventive measure, polyps should be removed (polypectomy).

Ureterosigmoidostomy. People who have had ureterosigmoidostomy, a surgical procedure to correct a birth defect in the bladder or to treat some bladder cancers, may develop tumors near the site of the defect, which is chronically exposed to urine and feces. Such patients have a 5 - 10% chance of developing colon cancer 15 - 30 years after the operation.

Diabetes. Many studies have identified an association between type 2 diabetes and colon cancer. Both diseases share common risk factors of obesity and physical inactivity, but diabetes itself is a risk factor for colorectal cancer. Both men and women who have diabetes are at risk.

Heart Disease. Coronary artery disease (CAD) increases the risk for colorectal cancer. Both CAD and colorectal cancer share important risk factors, including smoking, high fat diet, sedentary lifestyle, and obesity.

Dietary Factors

Some, but not all, studies have suggested that a high intake of fruits and vegetables can lower the risk for colorectal cancer. One study, for example, reported that these foods do not prevent polyps from forming but may help prevent them from becoming cancerous.

Phytochemicals. Many studies have demonstrated the cancer-fighting effects of plant chemicals called phytochemicals. Fruits and vegetables that contain phytochemicals can often be identified by colors:

Dark green (broccoli, spinach, kale, collard greens, mustard greens). These vegetables contain chemicals called isothiocyanates, which have been associated with a lower risk for cancer in general.
Red (red pepper, tomatoes, watermelon, raspberries, pink grapefruit). Lycopene is a chemical found in these foods that may have strong cancer-protective properties. Cooking tomatoes appears to increase their benefits.
Yellow-orange (carrots, pumpkin, sweet potatoes, oranges, tangerines). The colors in these foods are due to carotenoids. Carotenoids have been associated with health protection, although they may not have much effect on colon cancer itself.
Blue-black (many berries). Dark berries appear to have potent antioxidant chemicals that may be protective against cancer.

Organosulfurs are important food chemicals that are part of the allium family. Studies have reported health benefits from foods containing them. These compounds are found in garlic, leeks, onions, chives, scallions, and shallots. A review of 300 studies concluded that people who eat raw or cooked garlic regularly experience about two-thirds the risk of colorectal cancer as people who eat little or none. Another analysis, however, found the available evidence about garlic to be inconclusive. Garlic supplements, in any case, do not appear to be protective.

Fiber. Studies have been mixed on whether fiber (found in fruits, vegetables, and whole grains) protects the colon from cancer. For example, three major studies in 2002 and 2003 reported no difference in the development of colorectal polyps or cancer recurrence with high intake of fiber. On the other hand, results of the 2003 European Prospective Investigation into Cancer and Nutrition (EPIC) -- the largest study ever conducted on the role of diet in the development of cancer -- suggested that fiber is protective regardless of its source. However, in the study, the greatest benefits were observed for the left side of the colon and the least for the rectum. In any case, fiber, which is only found in plant products, may be beneficial for the heart and have other health advantages.

The role of fats in inflammatory bowel disease is complex and not fully known. A 2006 study from the Women’s Health Initiative found that a low-fat diet did not help reduce the risk for colorectal cancer. However, the study did not distinguish between types of fat.

Monounsaturated fats (olive, peanut, canola oils; avocados, nuts) and omega-3 polyunsaturated fats (fish, flaxseed oil, walnuts) are the healthiest types of fats.
Saturated fats (red meat, butter, high-fat dairy products) and trans-fats (hydrogenated fat found in snack foods, fried foods, commercial baked goods) are unhealthy types of fats.

Dietary guidelines recommend that adults limit the total fat in their diet to 25 - 35% of total daily calories. Saturated fat intake should be less than 7%, and trans fats less than 1%, of total daily calories. (Patients with heart disease or diabetes may need to limit unhealthy fat in their diet even further.) Most fats should come from polyunsaturated and monounsaturated fat sources.

[See In-Depth Report #43: Heart healthy diet; and #42: Diabetes diet.]

Evidence strongly suggests that red meat raises the risk for colon cancer development, and perhaps also recurrence. Red meat contains dietary iron, which has been associated with a higher risk for colon cancer.

High-temperature cooking (grilling, broiling, or pan-frying) has been specifically associated with increased risk for colon polyps and colon cancer. Overcooking meat increases the amount of carcinogens called heterocyclic amines, which has been associated with cancerous changes.

Milk, Lactose, and Probiotics. In one study, adults who drank the most milk had the lowest risk for colon cancer. A 2004 study published in the Journal of the National Cancer Institute supported this conclusion. In this review of 10 epidemiologic studies that included more than 500,000 people, those who consumed more milk and calcium had a lower risk of developing colorectal cancer. Milk contains not only calcium but also other compounds, such as lactose, that may help protect against colon cancer.

Yogurt specifically has been associated with a lower risk for colon cancer if it contains live active bacterial cultures, such as Lactobacillus acidophilus, that are called probiotics. These "friendly bacteria" appear to protect the colon from cancerous changes. (Acidophilus and other probiotic capsules are also available in health food stores.)

Calcium. Calcium, which is found in dairy products, is associated with colon cancer protection. Many studies have shown a possible protective effect from either high-calcium diets or calcium supplements. However, a 2006 study from the Women’s Health Initiative found that calcium and vitamin D supplements do not reduce women’s colorectal cancer risk. Many doctors still recommend that postmenopausal women take these supplements for bone health.

Obesity has been associated with colon cancer. In some studies of people under 67 years old, the amounts of fat and protein were less important than the total number of calories consumed: the higher the energy intake, the greater the risk for developing colon cancer. In older adults, high calorie intake did not make any significant difference. Other studies have indicated that eating too much sugar may increase the risk for colon cancer.

Studies conducted in several countries have found that drinking four or more cups of coffee a day is associated with a lower risk for colorectal cancer. Green tea may have also beneficial properties, but more research is needed in both of these areas.

Folate and B Vitamins. For years, many doctors have believed that the B vitamin folate (called folic acid) may help protect against colorectal cancer, particularly for people who are genetically predisposed to this disease. Folate is found in beans, citrus fruits, and green vegetables, but some studies have indicated that the greatest protective benefits come from taking supplements.

However, an important study published in 2007 in the Journal of the American Medical Association challenged this assumption. The study suggested that high-dose folic acid supplements do not prevent colorectal cancer, and may actually increase the risk for developing certain types of colorectal tumors. The study evaluated over 1,000 men and women who had a recent history of non-cancerous colorectal polyps. (Adenomatous polyps, also called colorectal ademomas, are the most common type of polyp found in colorectal cancer screenings.) The results indicated that patients who took 1 mg/day of folic acid supplements were more likely to develop new adenomatous polyps than patients who did not take supplements. Patients in the folic acid supplement group were also more likely to have advanced adenomas and more numerous adenomas.

Adenomatous polyps are benign tumors, but they can potentially develop into cancerous tumors. Researchers are continuing to investigate the role that folic acid plays in colorectal cancer risk and prevention. It is possible that folic acid may help prevent the initial appearance of adenomatous polyps, but increase the risk for additional polyp formation once they have begun to occur.

Antioxidant Supplements. Antioxidants are chemicals that help eliminate harmful particles called oxygen-free radicals that have been associated with cancerous changes. Some studies have associated supplements of the antioxidants selenium and vitamins A, C, D, and E with lower colon cancer risk, but most studies have found no protective effect.

Prevention

Studies indicate that daily exercise is one of the best ways to reduce the risk of colorectal cancer. The more vigorous the activity, the greater the benefit, but even moderate exercise (walking, stair-climbing) can help reduce colorectal cancer risk. The American Cancer Society (ACS) recommends that people engage in at least moderate exercise for 30 minutes or more at least 5 days a week. The ACS also notes that 45 minutes or more of moderate-to-vigorous activity at least 5 days a week may help further reduce cancer risk.

Some studies also suggest that regular exercise may be beneficial for patients who have been diagnosed with colorectal cancer. Two 2006 studies indicated that exercise may reduce the risk of colorectal cancer recurrence and death for patients with stage I - III cancer.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are very common pain relievers that are available over-the-counter and by prescription. They include aspirin, ibuprofen (Motrin), naproxen (Aleve), and the COX-2 inhibitor celecoxib (Celebrex). Several studies have reported that NSAIDs help reduce the risk of colorectal cancer. However, regular use of NSAIDs, even in low doses, can increase the risk of gastrointestinal bleeding and stomach ulcers. Long-term use of NSAIDs can also increase the risk for heart attack and stroke, especially in people who have a history of heart disease. Several 2006 and 2007 studies in the New England Journal of Medicine reported that celecoxib prevented precancerous polyps, but the drug more than doubled patients’ risk for heart attack and other cardiovascular events.

A 2005 Nurse’s Health Study found that aspirin, but not other NSAIDs, does provide protection against colorectal cancer. However, the risk was only reduced for women who took 2 aspirin a day for more than 10 years. In addition, this dose level greatly increases the risk for gastrointestinal bleeding. Furthermore, a 2007 study in the New England Journal of Medicine suggested that aspirin’s protective effects may only apply to some types of colorectal cancer tumors. Another 2007 study, published in the Lancet, indicated that long-term daily use of aspirin can protect against polyps and colorectal cancer, but experts agree that aspirin’s risks do not outweigh its benefits for most people. (Some people who are at high risk for developing colorectal cancer may benefit from aspirin therapy.)

In March 2007, the U.S. Preventive Services Task Force (USPSTF) recommended against the routine use of aspirin and other NSAIDs to prevent colorectal cancer in people at average risk for this disease. (This recommendation does not apply to people who have a family history of colorectal cancer or who are at high risk for developing colorectal cancer due to other risk factors.) Long-term use of NSAIDs can increase the risk for gastrointestinal bleeding, kidney function problems, and heart problems. Aspirin can also increase the risk for hemorrhagic stroke. Due to these risks, the American Cancer Society and other professional associations also recommend against the use of NSAIDs or other types of medications for colorectal cancer prevention.

Medications containing 5-aminosalicylate (5-ASA) are sometimes given to patients with ulcerative colitis to help control inflammation. These drugs, which include sulfasalazine and mesalamine, are chemically related to aspirin. A 2005 review of clinical trials found that patients with ulcerative colitis who used 5-ASA were 49% less likely to develop colorectal cancer than patients who did not use these drugs

Some studies have suggested that cholesterol-lowering statin drugs may help reduce colorectal cancer risk. A 2006 study in the Journal of the National Cancer Institute did not find any protective benefit for statins.

Estrogen has been associated with a lower risk for colon cancer, perhaps because of specific enzymes that prevent cell proliferation. Drugs containing estrogen, then, may help high-risk women:

There is some evidence that hormone replacement therapy (HRT) reduces the risk of colon cancer in postmenopausal women. It carries other risks, however, including a higher risk for breast and uterine cancer and blood clots. A 2004 New England Journal of Medicine study found that while short-term use of estrogen plus progestin reduced the risk of developing colon cancer, combination HRT users who were diagnosed with the disease had more advanced forms of the cancer. Older women who are at higher risk for colon cancer might discuss risks and benefits of HRT with their doctor.
Oral contraceptives may reduce younger women's risk of colon cancer. Duration of use does not seem to be associated with decreased risk, but protection appears stronger for women who have more recently used oral contraceptives.

Diagnosis

Colon and rectal cancers are diagnosed using the screening tests discussed below. These tests can detect precancerous polyps and colorectal cancers at stages early enough for complete removal and cure.

Unfortunately, only 30 - 40% of adults over 50 years old (mostly in the upper socioeconomic group) have regular screening tests that could detect a cancer early enough for curative treatment. A survey reported that many people are not screened because they are too embarrassed. Those who had already had the tests were willing to have them again if they saved one additional day of their lives.

There is some debate about what is the best screening method. Current screening guidelines offer several different options for patients. Doctors agree that not enough people are screened and that these tests, if adopted with the same regularity as such screening tests as Pap smears, would save many lives. It is especially important for anyone at increased risk or with symptoms, such as rectal bleeding or ulcerative colitis, to have testing at an earlier age.

There is also debate about when people should stop being screened. A 2006 study in the Journal of the American Medical Association indicated that screening provides little benefit for elderly people, especially because colorectal cancers grow very slowly. The researchers suggest that doctors should carefully consider the risks versus benefits of screening patients age 80 and older.

Individuals should discuss with their doctors the risks and benefits of all screening procedures. Some controversy exists over how often people without risk factors for cancer should be screened and which detection method should be used for them.

Guidelines for Adults Age 50 and Over with Average Risk. The following are the five screening options recommended for people age 50 and over who have no symptoms and no family history of colon cancer:

Fecal occult blood test (FOBT) or fecal immunochemical test (FIT) every year
Flexible sigmoidoscopy every 5 years
FOBT or FIT every year plus sigmoidoscopy every 5 years
Double-contrast barium enema every 5 years
Colonoscopy every 10 years

Choosing between Colonoscopy and Sigmoidoscopy. The choice between colonoscopy and sigmoidoscopy for routine screening for older adults with average risk is an area of intense debate. The issues are as follows:

Sigmoidoscopy is less costly, less invasive, quicker, and safer than colonoscopy. Although it allows inspection of only the left side of the colon, any abnormal findings from sigmoidoscopy trigger a full colonoscopy. Therefore, experts estimate that sigmoidoscopy can detect 80% of all significant problems.
Colonoscopy is more sensitive than any other current screening method for detecting colon cancer. It can find 75 - 90% of colorectal cancers. If the goal were to reduce the number of cancer cases, regardless of cost, colonoscopy would be the preferred approach. Colonoscopy, however, is more expensive than sigmoidoscopy and has a slightly higher risk for complications (bowel tears or bleeding when a polyp is removed).

There are 3 basic tests for colon cancer: a stool test (to check for blood), sigmoidoscopy (inspection of the lower colon), and colonoscopy (inspection of the entire colon). All 3 are effective in catching cancers in the early stages, when treatment is most beneficial.

Screening, particularly with colonoscopy, in increased- and high-risk populations can save lives. The most important risk factors are a family history of colorectal cancer and personal history of colorectal cancer, polyps, or chronic inflammatory bowel disease. People with these risk factors should be screened before age 50 and may need more frequent screenings.

Guidelines for Increased-Risk Groups. Anyone with first-degree relatives diagnosed with colon cancer younger than 60, or with two relatives who have been diagnosed with colon cancer at any age, should consider beginning the standard screening regimen with a colonoscopy every 5 years, beginning at age 40 or 10 years before the youngest case in the family (whichever is earlier).

Men of African descent are also considered to be at increased risk for colon cancer and should discuss similar screening guidelines with their doctors.

Guidelines for High-Risk Groups. The following guidelines may be useful for specific high-risk groups.

People who have the mutated hereditary nonpolyposis colorectal cancer gene (MSH2 or MLH-). Frequent colonoscopy (for instance, every 1 - 2 years) beginning in their early 20s. (Regular screening for other cancers, such as uterine cancer, is also reasonable.)
People who have the mutated familial adenomatous polyposis (FAP) gene. Frequent screening with endoscopy (flexible sigmoidoscopy or colonoscopy) beginning in early puberty. Genetic testing is now recommended for family members of people with known FAP.
People with predisposing intestinal problems, such as widespread and active ulcerative colitis or Crohn's disease. Annual screening with colonoscopy with biopsies of suspicious areas.

Guidelines for Follow-Up After Detection of Precancerous Polyps. Patients who have had a previous examination in which polyps were detected (and removed) should have a repeat colonoscopy 1 - 3 years later, depending on the size, number, and type of polyps removed.

The digital rectal examination is used to detect tumors in the rectum, lower intestine, and prostate gland. The doctor inserts a lubricated-gloved finger into the patient's rectum and feels for lumps or other abnormalities. The exam is quick and painless but embarrassing for some. Fewer than 10% of colon cancers develop within the region that can be evaluated by a DRE, so it is not useful as a sole screening test.

Blood in bowel movements is not always visible, in which case it is called occult (hidden) blood. Fecal occult blood tests (FOBTs) are used to detect this hidden blood. The most common FOBT method is called the guaiac-based test. The patient is asked to supply up to six stool specimens in a specially prepared package. A small quantity of feces is smeared on specially treated paper, which reacts to hydrogen peroxide. If blood is present, the paper turns blue.

Accuracy. FOBTs can miss more than 75% of advanced cancers. Nevertheless, large studies have indicated that this simple test, performed annually, saves lives and may reduce the risk of dying from colon cancer by 15 - 33%. The following factors may affect its accuracy:

The levels of iron in the blood can affect results. Patients should not take iron supplements or eat red meats several days before the test.
Certain raw fruits and vegetables that contain the chemical peroxidase (cauliflower, horseradish, radishes, melons, and turnips) can cause a positive test reaction even if no blood is present.
Aspirin and NSAIDs are anticoagulants that can cause minor bleeding. They should not be taken for a week before the test. However, a 2005 study suggested that the prescription anticoagulant warfarin does not affect FOBT results.
Vitamin C and foods rich in this vitamin may cause a false negative reaction and should be avoided a few days before the test.
Bleeding from other causes, such as menstruation, hemorrhoids, gingivitis, or urinary infections, can produce blood in the stools and affect results.

Even if none of these conditions is present, a test that shows hidden blood does not necessarily mean that cancer is present. About 20 - 30% of people with occult blood have noncancerous polyps or other conditions, such as gastritis, and only 5 - 10% actually have cancer. Any abnormal result, however, requires further testing, such as colonoscopy.

Lack of Compliance. Compliance is a major problem. Patients are asked to perform the tests at home and send the test cards to the laboratory. Only 35 - 50% of patients actually follow through. Occult-blood tests that give results at home are available but are extremely inaccurate. In one large study, these tests failed to detect advanced cancer in about 62% of cases, although they may detect some early cancers.

If a digital rectal exam (DRE) or fecal occult blood test (FOBT) shows signs of trouble, several methods to visualize the colon are available. They include colonoscopy, sigmoidoscopy, and double-contrast barium enema. They have the following similarities and differences:

Sigmoidoscopy can only view the rectum and the left side of the colon, while colonoscopy and barium enemas allow a view of the entire large intestine.
Both flexible sigmoidoscopy and colonoscopy involve snaking a fiber optic tube through regions of the rectum and colon to view the walls of the intestine. The tube contains a tiny camera that transmits the image to a video screen. The use of an ultrasound (sound wave) scanner is proving to enhance viewing quality. Barium enemas simply use x-rays.
During either sigmoidoscopy or colonoscopy, the doctor is able to remove polyps or other abnormalities revealed by these procedures with surgical instruments inserted through the tube. It is not possible to remove polyps with a barium enema, which is not invasive.

Sigmoidoscopy. Sigmoidoscopy examines the rectum and the lower two feet of the colon. It cannot, however, detect the roughly half of cancers that occur in the right colon. Right-sided cancers are more common in older people.

The procedure uses a flexible fiber optic tube (it is thus referred to as flexible sigmoidoscopy) that contains a tiny camera and surgical instruments.
It lasts about 10 minutes and may be mildly uncomfortable, but it is not painful and is generally very safe. In one study, 70% of patients reported that the procedure was far less unpleasant than they had expected.

This procedure has been found to reduce the risk of fatal cancers in the rectal and sigmoid area by 60%. If polyps are detected, a colonoscopy is then used.

Colonoscopy. Colonoscopy is the most accurate testing method and can reduce cancer incidence by up to 90%. It is clearly indicated for anyone with an increased risk for colorectal cancer, including those with a personal or family history of the disease. As with sigmoidoscopy, a colonoscopy uses a flexible tube, but it is snaked through the entire large intestine.

For about a day before the procedure the patient eats nothing and drinks a laxative solution that cleans out the colon. The taste of the solution is unpleasant, although it has improved in recent years.
The procedure typically uses a sedative that produces a "twilight" sleep and often makes the procedure more comfortable than sigmoidoscopy.
Air may be introduced into the intestine to widen it and allow the tube to navigate curves. A colonoscopy avoids the risk of radiation associated with a barium enema, but it is important to note that even a colonoscopy does not detect all cancers.

Complications are rare, but include the following:

Hyponatremia. Hyponatremia is a low concentration of sodium in the blood. The complication may be caused by the effects of bowel cleaning before the procedure that can result in water retention and reductions in sodium. When severe, it can cause temporary neurological symptoms, such as confusion, lethargy, unsteadiness, and slurred speech. Researchers suggest that sodium concentrations be measured in patients who develop such symptoms after colonoscopy.
Bowel perforation (very low risk, about 2 in 1,000 procedures). The risk for bowel perforation is greater with colonoscopy than flexible sigmoidoscopy.
Bleeding at the site of biopsy or polyp removal.

Overall, colonoscopy is a safe procedure. However, according to a 2006 study in the Annals of Internal Medicine, serious complications occur in about 5 of every 1,000 colonoscopies. Most of these complications occurred when a biopsy or polyp removal was performed. (The risk for complications without biopsy or polyp removal is about 1 in every 1,000 colonoscopies.) This study looked at colonoscopies in general, including those that are done to diagnose the causes of a patient's symptoms. The risk may be lower for colonoscopies performed solely to screen for colorectal cancer.

Barium Enema. The double-contrast barium enema, which uses an x-ray image, is the less expensive alternative for viewing the entire colon. It is not as accurate as colonoscopy, and if any polyps or abnormalities are revealed on x-ray, a colonoscopy is then required to remove suspicious tissue, so it is now recommended much less often than in the past.

The barium enema is a valuable diagnostic tool that helps detect abnormalities in the large intestine (colon). The barium enema, along with colonoscopy, remains the standard in the diagnosis of colon cancer, ulcerative colitis, and other diseases of the colon.

Screening for familial adenomatous polyposis. Genetic screening for familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon cancer (HNPCC) is now available and may be recommended for high-risk patients. The test for FAP detects a mutation in the adenomatous polyposis coli in up to 90% of people who carry it. Testing for HNPCC mutation is somewhat more complex.

Screening for insulin-like growth factor. A gene that regulates insulin-like growth factor (IGF-2) is functional during fetal development and then becomes inactive. Some evidence now suggests that people who have IGF-2 in adulthood have a higher risk for colon cancer. Blood tests for detecting IGF-2, then, may be helpful in identifying patients who should have more intensive screening. Currently, however, this is only used as a research tool.

Stool DNA Testing. A promising technique for colorectal cancer screening is the detection of altered DNA in cancer cells that have shed from the colon and are excreted in the stool. Such tests may prove to detect both inherited and noninherited genetic mutations. This may become a widely used tool in the future. However, larger clinical studies are needed.

Virtual Colonoscopy. A promising experimental technique called virtual colonoscopy allows three-dimensional imaging of the colon without using invasive instruments. As with standard colonoscopy, the patient takes a laxative first to clear out the intestine. The procedure itself involves pumping air into the colon and scanning the intestine using computed tomography (CT). It is very safe and takes about only 10 minutes. The procedure is similar in accuracy to conventional colonoscopy for detection of larger polyps (6 mm or more in diameter) and is also potentially less expensive. Colonoscopy is required, however, if suspicious areas are found, which may occur frequently with the CT procedure, since it erroneously identifies a high number of nonexistent polyps.

A study published in April 2004 in the Journal of the American Medical Association compared results of standard colonoscopy versus virtual colonoscopy in over 600 patients at nine major medical centers. Virtual colonoscopy had much lower rates of successfully finding polyps than standard colonoscopy. Virtual colonoscopy detected polyps of at least 6 mm in 39% of patients and polyps of at least 10 mm in 55% of patients. By contrast, standard colonoscopy detected 99% of polyps of at least 6 mm, and 100% of polyps of at least 10 mm. In addition, accuracy rates varied widely among the different hospitals. The authors advised that until more improvement in training and technique is achieved, virtual colonoscopy "is not yet ready for widespread clinical application."

Magnetic Resonance Colonography. Magnetic resonance colonography (MRC) is another non-invasive technique for visualizing the colon. The patient receives an enema containing a contrast substance, and then magnetic resonance images are taken. MRC is fast, comfortable, and less invasive than colonoscopy. Currently, however, there is a poor detection rate for flat tumors and for polyp tumors less than 10 mm in diameter.

Staging

A diagnosis of cancer will lead to staging and other tests to help determine the outlook and the appropriate treatments.

The large intestine is a long hollow organ lined with mucous membrane (mucosa). Muscle layers wrap around the entire length and help move food material through to the rectum.

Unlike many other cancers, the size of the tumor is not a major factor in determining the outcome of colorectal cancer. Of greater importance is how far the cancer has spread. To determine this, doctors will assign a stage to the tumor. There are several methods for staging. The older system, known as Dukes', categorizes four basic stages: A, B, C, and D. A more recent system refers to these stages as I, II, III, and IV but divides the categories slightly differently. The term "5-year survival" means that patients have lived at least 5 years since diagnosis. Most patients who live 5 years without a recurrence are considered to be cured of their disease.


Stage	Condition	5-Year Survival
A or I	Tumor superficially involves the inner lining of the intestine.	More than 90%
B or II	Tumor has penetrated through the muscle wall of the intestine but has not reached the lymph nodes.	70 - 85%
C or III	Lymph nodes are involved.	65% or below
D or IV	Tumor has spread to other organs (metastasized), usually the liver first.	5 - 9%

Click the icon to see an image of the stages of cancer.

Researchers are continually seeking to identify tumor markers, substances (usually found in blood samples) that will assist in the diagnosis of cancer and in monitoring effects of treatment.

Carcinoembryonic Antigen. High blood levels of a protein called carcinoembryonic antigen (CEA) sometimes indicate the presence of colon cancer. Unfortunately, it is also elevated in other cancers and in some noncancerous conditions. CEA is not effective as a screening tool for healthy people, but might eventually be helpful for patients with cancer.

An advanced diagnostic technique called polymerase chain reaction (PCR) can detect genetic evidence of CEA. One study indicated that when these microscopic footprints of colon cancer are detected in the lymph nodes of patients with Stage II cancer (whose lymph nodes otherwise appear to be not involved with cancer), the outlook is similar to that of patients with Stage III cancer. Patients without this so-called micrometastasis have a very favorable prognosis. Further research is needed, however, before PCR can be used in widespread practice.
In patients with a history of, or active, colon cancer, follow-up measuring of blood CEA levels may be helpful in detecting recurrence of the cancer and effectiveness of treatments.

Defective P53 Gene. The presence of a defective p53 gene is a marker for very poor prognosis in patients with advanced colon cancer. In its normal state, the gene is important for regulation of cell growth. Testing for this abnormality, however, is not widely done because it is not clear how to use this information.

Other Tumor Markers. Other tumor markers under investigation include a protein called GLUT1, cancer antigen 19-9 (CA 19-9), matrix metalloproteinase-9 (MMP-9) RNA, HER-2/neu oncoprotein, transforming growth factor beta-1 (TGF-beta-1), and CD44.

Click the icon to see an image of drawing blood for culture.

A technique known as a sentinel node biopsy is increasingly performed by experienced surgeons in selected patients. This procedure is used to determine if cancer has spread beyond the nodes, possibly reducing the need for complete axillary lymphadenectomies. It involves the following:

The procedure uses an injection of a tiny amount of a tracer, either a radioactively-labeled substance (radioisotope) or a blue dye, into the tumor site.
The tracer or dye then flows via the lymphatic system into the so-called sentinel node. This is the first lymph node to which any cancer would spread.
The sentinel lymph node and possibly one or two others are then removed.
If they do not show any signs of cancer, it is highly likely that the remainder of the lymph nodes will be cancer free, and further surgery becomes unnecessary.

It is still not known if the sentinel node biopsy has any survival advantages compared to the standard procedures with lymph nodes removal. However, one study indicated that careful and complete removal of potentially cancerous lymph nodes is still very important for improving survival in patients with Stage II and III colorectal cancer.

Whole-body imaging scans that combine positron emission tomography (PET) and computed tomography (CT) may be helpful in accurately staging colorectal cancer, according to preliminary research published in 2006 in the Journal of the American Medical Association.

Prognosis

Survival rates for colorectal cancer have been rising in recent years. The 5-year survival rate is as high as 90% for cancer that has not spread to the lymph nodes (localized cancer). When cancer has spread to lymph nodes and other parts of the body, survival rates drop to 65% and below. Because many cancers are detected at later stages, the overall survival rate is currently about 60%. African-Americans and other minorities tend to have lower survival rates than Caucasians. Studies suggest, however, these higher mortality rates are largely due to less access to optimal health care, including appropriate surgical care and aggressive treatments.

In most cases, age is not a factor in treatment success. Good survival rates are achieved in the elderly as well as in young people. Chances for survival are less in Stage II cancers if the intestine is obstructed or perforated. If cancer has spread to lymph nodes (Stage III), the outlook is better if three or fewer lymph nodes are involved. Treatment can prolong life even when cancer has spread.

Surgery

Surgical removal of the tumor ("resection") along with any affected surrounding tissue is the standard initial treatment for potentially curable colorectal cancers (cancers that have not spread beyond the colon or lymph nodes). Drug and radiation therapy are often used for advanced cancers and are continuously being tested with surgery in different combinations and sequences.

Although choosing a qualified surgeon is critical, choosing a hospital experienced in procedures is also important. The more often colon cancer surgery is performed at a given hospital, the lower the mortality rate at that hospital is likely to be.

Unless cancer is very advanced, most tumors are removed by an operation known as colectomy:

Colectomy involves removing the cancerous part of the colon and nearby lymph nodes.
The surgeon then reconnects the intestine.
If the surgeon cannot reconnect the intestine, usually because of infection or obstruction, the surgeon will perform a colostomy. The need for colostomies is higher after surgery for rectal cancer. In most cases of colon cancer, colostomies are not needed. [See "Colostomy" below.]

Click the icon to see an illustrated series detailing colon cancer treatment.

The Surgical Approach. The standard technique for a colectomy is open, invasive surgery. Laparoscopy, sometimes called “keyhole surgery,” is a less invasive method. Laparoscopy is still considered an investigational technique for treating colon cancer, but it is gaining more acceptance and showing good results in clinical trials.

Open Surgery:

Open surgery uses a wide incision to open the patient's abdomen. The surgeon then performs the procedures with standard surgical instruments. This is the usual method for performing colectomy.

Laparoscopy:

Laparoscopy uses a few small incisions through which the surgeon passes a fiber optic tube (laparoscope) containing a small camera or tiny instruments. It is generally used for early colon cancer (for tumors less than 2 centimeters or for well-defined tumors less than 3 centimeters).
A 2004 New England Journal of Medicine study found that patients who received laparoscopic colectomy had similar rates of surgical complications, cancer recurrence, and survival as those who received traditional open surgery. However, the patients who had laparoscopy recovered faster and did not need as many narcotic painkillers.
Several 2005 studies indicated that laparoscopy works as well as conventional surgery for treatment of colon cancer. However, laparoscopy does not appear to be as effective for rectal cancer.

Click the icon to see an image detailing pelvic laparoscopy.

Click the icon to see an illustrated series detailing a resection of the large intestine.

Other Investigational Measures. Researchers are testing expandable metal tube-like devices called stents to keep the intestine open. Stents may be used before a procedure to allow bowel cleansing or for long-term use to keep open colons that can't be operated on.

A colostomy is performed in order to bypass or remove the lower colon and rectum. The procedure generally involves creating a passage, called a stoma, through the abdominal wall that is connected to the colon. The feces pass through this passage and are eliminated. Patients must learn how to care for the stoma and keep the area sanitary.

A colostomy usually will have one opening (single-barreled), or there may be two loops opening through the skin (double-barreled).

Usually the colostomy is temporary and can be reversed by a second operation after about 3 - 6 months. It the rectum and sphincter muscles in the rectum need to be removed, the colostomy is permanent. Permanent colostomies are more common when the cancerous regions are within 2 - 3 centimeters of the anus. Fortunately, surgical advances and knowledge of the extent of safe margins are reducing the need for permanent colostomies.

Click the icon to see an illustrated series detailing a colostomy procedure.

Managing Permanent Colostomies. In cases where the colostomy is permanent, the patient must wear a colostomy pouch, which sticks to the skin using a special glue. Pouches are available as one- or two-piece systems. The one-piece system is simpler, but the two piece system allows replacement of the pouch without removing the tape.

For best results, the pouch should be emptied when about one-third full. It should be replaced 1 - 2 times a week, depending on signs of leakage (itching or burning of the skin near the stoma). The pouches are odor proof.

Surgical treatments for cancer in the rectum are complex since they involve muscles and tissue that are critical for urinary and sexual function.

Local Excision or Polypectomy for Early Stages. In order to preserve the function of the anal sphincter and prevent the need for colostomy, Stage I and Stage II tumors may be removed by local excision, sometimes followed by chemotherapy and radiation. In this procedure, the tumor is cut out without removal of a major section of rectum. In some cases cancer recurs, but a second operation may be possible. Another treatment for early-stage rectal cancer, called electrocoagulation, destroys tumors using a high frequency electric current. It is being tested in clinical trials.

Radical Resection. In about a third of cases of rectal cancer, the cancer occurs in the lower part of the rectum, where between 70 - 80% of cancers have spread beyond the rectal wall. These patients need a radical resection, in which surrounding structures, including the sphincter muscles that control bowel movements, must often be removed.

The use of chemotherapy and radiation prior to surgery may prevent the need for permanent colostomy in some patients. This is an active area of clinical research, and trials are under way to address this issue. Another technique, called coloanal anastomosis, reconstructs the area to avoid the need for colostomy, and may be appropriate in some patients.

Total Mesorectal Excision. Total mesorectal excision (TME) involves dissection and removal of the entire cancerous area of the rectum along with surrounding fatty regions where the lymph nodes are located (the mesorectum). When successful, TME preserves the sphincter muscle, reducing the need for a permanent colostomy. Increasing use of this procedure is resulting in lower recurrence rates, lower levels of impotence and incontinence, and better overall survival rates compared to other resection techniques. Some experts now recommend it as a first choice for certain patients with locally advanced rectal cancer.

Combining chemotherapy and radiation either before or after TME is yielding promising long-term results and a low risk for local recurrence. There are many questions, however, and it is not clear which approach is better for specific patients.

Side effects of colon surgery include:

Sexual dysfunction. This is of particular concern. In general, colostomy does not usually affect sexual function. However, wide rectal surgery can cause short- or long-term sexual dysfunction. Sildenafil (Viagra) may help men who experience this after surgery.
Irregular bowel movements.
Gas and flatulence. Pouching filters are available to reduce gas. Certain foods produce more gas than others -- usually within 6 - 8 hours after ingestion for colostomy patients. They include beans, oat bran, most fruit, and certain vegetables (cabbage, cauliflower, Brussels sprouts, broccoli, and asparagus). To prevent swallowing air, patients should avoid sipping through straws, chewing gum, and chewing with their mouths open.
Diarrhea.
Bladder complications.
Sense of urinary urgency.
Fecal incontinence. Patients with rectal surgery have a higher risk for bowel dysfunction than those who had a colostomy.
Complications in or around the stoma. These can occur early after surgery to many years after the procedure. They include skin infection or breakdown, hernias, narrowing of the stoma, bleeding, and collapse.

There are no dietary restrictions, although many patients avoid foods that can produce gas. Everyone should drink plenty of fluids and get sufficient fiber.

The potential side effects of sexual and bowel dysfunction for colorectal surgical patients can be devastating, although many patients do very well and live normal productive lives. Positive emotions play a strong role in recovery. Patients who are depressed should discuss with a doctor all aspects of treatment that affect the quality of life, and consider seeking support groups.

Medications

Chemotherapy uses drugs that kill cancer cells throughout the body. There are two situations in which chemotherapy is used:

The adjuvant setting. Adjuvant refers to the use of chemotherapy after surgery in patients with Stage III tumors and selected patients with high-risk Stage II tumors (disease that is potentially curable). The goal of this therapy is to eliminate any cancer cells that surgery may have missed, thereby preventing recurrence and increasing the chance of cure. Patients of all ages, including the elderly, can benefit.
In metastatic disease. In patients with metastatic disease (where the cancer has spread to other parts of the body) the goal of chemotherapy is to shrink tumors, improve symptoms and quality of life, and lengthen life.

In the adjuvant setting, there are some differences in chemotherapy treatments between colon and rectal cancers:

Chemotherapy for Stage II is considered standard care for Stage II rectal cancer but is under debate for colon cancer.
Chemotherapy is standard for patients with Stage III colon cancer. Chemotherapy is also standard for patients with Stage III rectal cancer but is used in combination with radiation.

Chemotherapy for Stage II Colon Cancer. Adjuvant chemotherapy for Stage II colon cancer is controversial. Such patients tend to have a good outcome after surgery, and the positive effects of chemotherapy have been difficult to demonstrate. To date, the survival advantage of adjuvant chemotherapy in this group has been reported to be only in the range of 2%. However, better trials are still needed to confirm or refute the benefits in specific patient groups.

Although not yet known with certainty, some data suggest that certain patients with Stage II cancer may be at higher risk of recurrence and would theoretically benefit from adjuvant therapy. These include patients with cancers that have:

Obstructed the bowel
Perforated the wall of the colon
Adhered to structures outside the intestine

Advanced diagnostic techniques are under investigation for helping to select appropriate candidates for adjuvant therapy. None of these methods, however, are ready to be used routinely to help make treatment decisions. The decision whether to pursue chemotherapy for Stage II disease should be made after careful discussion between the patient and their oncologist, especially after features, such as bowel perforation or obstruction, are taken into account.

Chemotherapy for Stage III Colon Cancer. Since the early 1990s, adjuvant chemotherapy with 5-FU and leucovorin has been the standard of care for Stage III colon cancer. In recent years, the FOLFOX (5-FU, leucovorin, oxaliplatin) regimen has also been used for chemotherapy following surgery. Numerous trials have shown that adjuvant chemotherapy in this setting reduces the absolute risk of death from colon cancer by about one-third and improves survival by 10%. Clinical trials are also investigating combinations of other drugs.

Chemotherapy for Advanced Colorectal Cancer. Chemotherapy is either given directly into the arteries of the liver or intravenously (through a vein) with 5-FU and leucovorin. Oxaliplatin is sometimes added, but recent evidence suggests that the targeted therapy biologic drug bevacizumab may be a better addition. Other alternative chemotherapy choices are capecitabine, or irinotecan combined with cetuximab. Radiation therapy may be used in place of chemotherapy or in combination with it. Studies indicate that chemotherapy offers only a modest improvement in survival, but may help reduce symptoms.

Seven drugs are currently approved for colorectal cancer chemotherapy:

5-fluorouracil (5-FU, Adrucil), which is often given in combination with leucovorin (Wellcovorin). Leucovorin is a vitamin that helps boost the effectiveness of 5-FU.
Capecitabine (Xeloda)
Oxaliplatin (Eloxatin)
Irinotecan (Camptosar)
Bevacizumab (Avastin)
Cetuximab (Erbitux)
Panitumumab (Vectibix)

Capecitabine is a pill form of 5-FU. The other drugs are administered intravenously. Many of these drugs are given in combination with each other. Common chemotherapy combination regimens include:

5-FU / LV (5-FU and leucovorin)
FOLFOX (5-FU with leucovorin and oxaliplatin)
FOLFORI (5-FU with leucovorin and irinotecan)
IFL (Irinotecan, 5-FU, leucovorin)
XELOX (Capecitabine and oxaliplatin)

Side effects occur with all chemotherapeutic drugs. They are more severe with higher doses and increase over the course of treatment. Because cancer cells grow and divide rapidly, anticancer drugs work by killing fast-growing cells. This means that healthy cells that multiply quickly can also be affected. The fast-growing normal cells most likely to be affected are blood cells forming in the bone marrow, and cells in the digestive tract, reproductive system, and hair follicles. Nausea and vomiting is a very common side effect, but drugs such as ondansetron (Zofran) can help provide relief. In general, side effects are nearly always temporary, and medications can help manage them. Most patients are able to continue with normal activities for all but perhaps 1 - 2 days a month.

5-Fluorouracil (5-FU) with Leucovorin. Adjuvant therapy using 5-fluorouracil, either alone or with leucovorin (5-FU/LV), is the standard treatment for patients with high-risk colon cancer (Stage III or select patients with Stage II tumors). Leucovorin, also called folinic acid, is a form of the B vitamin folic acid, which helps increase 5-FU’s effectiveness. Patients are given a series of cycles that usually continue for at least 6 months.

There are many different ways of giving 5-FU, including intravenously over several hours once a week, intravenously daily for 5 consecutive days every month, or as continuous infusion with a portable pump.

The side effects can be quite different, depending on the way 5-FU is given, and women may be more susceptible than men. In one analysis, 53% of women and 40% of men experienced severe side effects, while response rates and survival were similar for both sexes. Many patients, however, tolerate 5-FU with leucovorin well, with manageable side effects. The most common side effects include nausea and vomiting, diarrhea, loss of appetite, hair loss, swelling of hands and feet, rashes, and mouth sores.

Irinotecan. Irinotecan (Camptosar) blocks an enzyme essential for cell division. Irinotecan can be given alone or in combination with 5-FU and leucovorin. This combination therapy (irinotecan plus 5-FU/LV) is also referred to as the "Salz regimen," or IFL. When it was approved in the mid 1990s, irinotecan was the first new drug developed for colon cancer in over 30 years. Studies have shown that irinotecan combined with 5-fluorouracil and leucovorin (5-FU/LV) significantly delays the time at which tumors progress and improves survival in metastatic cancer compared to 5-FU/LV alone. While the survival advantage is small, the combination has become the standard of care for metastatic cancer. Of concern, however, are studies that have reported an increased risk of death from toxic effects with the use of the three-drug combination. These deaths appeared to be related to blood-clotting complications. Doctors should carefully monitor dosages. Diarrhea is a common side effect of irinotecan.

Capecitabine. Capecitabine (Xeloda), an oral form of 5-FU, was approved in 2001 as a treatment for metastatic colorectal cancer. It is the only pill approved for colorectal cancer. A major 2005 study, published in the New England Journal of Medicine, found that capecitabine works as well as the standard 5-FU/LV regimen and causes significantly fewer side effects. The study involved patients with Stage III colon cancer who had undergone surgical removal of the tumor. In 2005, capecitabine was approved for postsurgical treatment of patients with Dukes’ C colon cancer. Capecitabine is also showing promise in combination with radiation therapy for rectal cancers.

Oxaliplatin. Oxaliplatin (Eloxatin) is related to cisplatin, a widely used platinum-based chemotherapy drug. Oxaliplatin is used in combination with 5-FU and leucovorin. (This triple combination therapy is called the FOLFOX regimen.) Oxaliplatin was first approved in 2002 for use in combination with 5-FU and leucovorin as a second-line treatment for cancer that has progressed after initial therapy.

Since 2002, oxaliplatin has received additional approvals as a first-line treatment for advanced colorectal cancer, and as a post-surgical treatment for patients who have undergone tumor resection.

Oxaliplatin can cause pain and tingling sensations in the hands and feet (neuropathy) that is worsened by exposure to cold. Recent research suggests that adding xaliproden (Xaprila) to the FOLFOX regimen may help reduce the frequency of neuropathy without interfering with the benefits of chemotherapy. Xaliproden is a drug used to treat the neurological disease amyotrophic lateral sclerosis (also known as Lou Gehrig's disease).

Bevacizumab. Bevacizumab (Avastin) was approved in February 2004 as a first-line treatment for patients with metastatic colorectal cancer (advanced cancer that has spread in the body). It is used in combination with IFL (irinotecan, 5-FU, leucovorin). Bevacizumab is a genetically engineered monoclonal antibody that targets and inhibits vascular endothelial growth factor (VEGF), a protein that regulates angiogenesis (the development of new blood vessels that feed a tumor's blood supply). It is the first anti-angiogenic therapy approved for the treatment of colorectal cancer.

In a study of 800 patients with metastatic colorectal cancer, bevacizumab administered intravenously along with IFL extended survival by about 5 months longer than IFL alone. Common side effects of bevacizumab include nosebleeds, fatigue, diarrhea, and high blood pressure. Less common side effects include stroke, heart attacks, angina, and formation of holes in the colon and stomach (gastrointestinal perforation).

Cetuximab. Cetuximab (Erbitux) was approved in February 2004 for the treatment of metastatic colorectal cancer. This monoclonal antibody drug targets epidermal growth factor receptor (EGFR), a protein required by cancer cells in order to proliferate. It can be used either in combination with irinotecan or alone for patients who have not responded to irinotecan. Studies of the cetuximab-irinotecan combination suggest it can help in tumor shrinkage. It has a modest effect on survival, prolonging patients’ lives by about an additional month.

Panitumumab. Panitumumab (Vectibix) was approved in September 2006 for treatment of colorectal cancer that has metastasized following standard chemotherapy. Like cetuximab, panitumumab is a monoclonal antibody drug that targets EGFR. In clinical trials, panitumumab helped delay disease progression and prolong survival by about 3 months. About 8% of patients experienced tumor shrinkage. Common side effects of this drug include skin rash, fatigue, abdominal pain, nausea, and diarrhea or constipation. Serious side effects include pulmonary fibrosis, severe skin rash, and skin reactions at the infusion site.

One of the most promising recent developments in cancer treatment research has been the emergence of so-called "targeted therapies." Traditional chemotherapy drugs can be effective, but because they do not distinguish between healthy and cancerous cells their generalized toxicity can cause severe side effects. Targeted therapies work on a molecular level by blocking specific mechanisms associated with cancer cell growth and division. Because they selectively target cancerous cells, they may induce less severe side effects. In addition, these drugs hold the promise of creating options for more individualized cancer treatment based on a patient's genotype. In the future, diagnostic tests may help doctors identify which patients are more likely to respond successfully to specific drugs.

Biologic therapies use the body's immune system to attack the cancer (immunotherapy). These drugs are derived from biological sources and include vaccines, monoclonal antibodies (MAbs), and gene therapies. Many targeted therapies are classified as biologics. Bevacizumab (Avastin), cetixumab (Erbitux), and panitumumab (Vectibix) are currently the three biologic drugs approved for colorectal cancer treatment, but many other drugs are in development.

Targeted therapies involve many different types of drugs and molecular pathways. These include:

Angiogenesis Inhibitors. Anti-angiogenesis drugs inhibit the formation of new blood vessels that supply tumors with the blood, oxygen, and nutrients vital to tumor growth. Angiogenesis inhibitors, such as the monoclonal antibody bevacizumab (Avastin), target vascular endothelial growth factor (VEGF). Cediranib (Recentin), formerly AZD2171, is a new angiogenesis inhibitor that is in Phase III clinical trials for treatment of colorectal cancer.

Tumor Growth Factor Inhibitors. Tumor growth factors, such as epidermal growth factor, stimulate cell growth. Cetixumab (Erbitux) and panitumumab (Vectibix) are the two currently approved colorectal cancer drugs that target the epidermal growth factor receptor (EGFR). Nimotuzumab (TheraCIM) is currently being studied in combination with irinotecan in Phase III trials.

Tyrosine Kinase Inhibitors. Tyrosine kinase is an enzyme associated with EGFR that is involved with the signaling mechanisms that prompt cell growth. The EGFR/tyrosine kinase inhibitor erlotinib (Tarceva), which is approved for the treatment of pancreatic and lung cancers, is being investigated as an adjuvant treatment for metastatic colorectal cancer. Sunitinib (Sutent), which is approved for renal cell carcinoma, is another tyrosine kinase inhibitor in Phase III trials for colorectal cancer.

Radiation Treatment

Radiation therapy uses x-rays to kill cancer cells that might remain after an operation or to shrink large tumors before an operation so that they can be removed surgically. The object of radiation therapy is to damage the tumor as much as possible without harming surrounding tissues. Radiation may be administered in the following ways:

Externally by an x-ray machine (external beam radiation).
By passing radioactive pellets through thin plastic tubes inserted into the intestine.
By implanting tiny radiation seeds directly into the tumor (brachytherapy).
Computer imaging techniques providing 3-dimensional pictures of the cancerous area are allowing precise targeting of radiation to the tumor.

Postoperative radiation treatment combined with chemotherapy is common practice for patients with rectal cancer in Stages II and III. Such patients are at risk of recurrence both at the site of their original tumor and elsewhere in the body. Although there can be significant long-term side effects, the combination of 5-FU and radiation is still considered standard after surgery.

The standard procedure in the U.S. is to apply radiation after surgery (postoperative). Pre-operative chemotherapy and radiation, however, are sometimes used to preserve sphincter-muscle function and reduce the chance that a patient will need a colostomy. Furthermore, some studies suggest that the use of radiation before surgery reduces the likelihood of recurrences and may slightly prolong survival in some patients with rectal cancer. (It has no additional advantages, however, if the subsequent surgery does not completely remove the cancerous regions.) Studies comparing preoperative and postoperative chemotherapy and radiation are currently under way.

Radiation therapy can also be used during surgery (a procedure called intra-operative radiotherapy). It allows the surgeon to move healthy tissue out of the path of the radiation beam.

Short-term side effects of radiation include:

Diarrhea
Skin irritation around the anus
Incontinence
Fatigue
Bowel movement problems

Longer-term complications may include:

Incontinence
Hip and pelvic fractures
Diarrhea
Increased risk for bowel obstruction

Follow-up Testing

The American Society of Clinical Oncology (ASCO) sets guidelines for follow-up testing to detect recurring cancer after the completion of treatment. The following guidelines are based on ASCO’s 2005 updated recommendations.

Most colorectal cancer recurrences happen within 3 years after surgery. American Society of Clinical Oncology recommends that a colorectal cancer patient sees their doctor for a physical examination every 3 - 6 months for the first 3 years, every 6 months for the fourth and fifth years, and at the doctor's and patient's discretion during subsequent years.

Patients should have a colonoscopy 3 years after surgery. If the results are normal, patients should then receive a colonoscopy every 5 years. Some patients with hereditary types of colorectal cancer may need more frequent screenings.

A flexible sigmoidoscopy is recommended every 6 months for 5 years for patients with Stage II or III rectal cancer who did not receive radiation therapy.

Carcinoembryonic antigen (CEA) levels should be measured every 3 months after surgery for 3 years in patients with Stage II or III cancer. High CEA levels in the blood may indicate that the cancer has spread to other parts of the body.

Patients at high risk for cancer recurrence should receive an annual computerized tomography (CT) scan for the first 3 years after treatment. The CT scan can help determine if cancer has spread to the lungs or liver. Patients who have had rectal cancer, and did not have radiation therapy, should receive a pelvic CT scan. The scan is not recommended for most lower-risk patients with Stage I or II colorectal cancer.

American Society of Clinical Oncology does not recommend other follow-up blood tests such as complete blood count, liver function tests, fecal occult blood tests. There appears to be no additional benefit for these tests.

Treatment for Metastasized Colorectal Cancer

The liver is the most frequent site for colorectal cancers to spread (metastasized). Here, treatments may slow the spread of cancer and even prolong survival. Cure is very rare.

When cancer has spread, surgery to remove or bypass obstructions in the intestine may be performed. In these circumstances, surgery is considered palliative in that it may improve symptoms but will not lead to cure. In rare cases, metastatic colon cancer may be cured with surgical removal of tumors in areas to which the cancer has spread, such as the liver, ovaries, and lung. The liver is the most common site of spread. Only selected patients may be eligible for such surgery, but in these patients, 5-year survival has been 25% or higher.

Chemotherapy may help improve symptoms and possibly prolong survival in metastasized colorectal cancers. Several investigational drugs are being tested. Doctors are also testing chemotherapy administered directly into the liver -- a treatment called hepatic arterial infusion (HAI). A 2006 study found that hepatic arterial infusion improves survival and quality of life for patients whose cancer has spread to the liver. The study indicated that HAI works better for these patients than chemotherapy delivered intravenously.

Other investigative techniques used to destroy liver tumors include:

Cryosurgery. This approach freezes the tumor or surrounding tissue.
Embolization. Embolization employs a catheter to deliver substances into the liver that block blood vessels and therefore starve the tumor. Chemotherapy is often administered during this procedure.
Radiation.

For end-stage cancer, hospice care is a compassionate option.

Resources

www.cancer.org -- American Cancer Society
www.cancer.gov -- National Cancer Institute
www.oncolink.org -- OncoLink cancer information
www.asco.org -- American Society of Clinical Oncology
www.plwc.org -- People Living with Cancer
www.nccn.org -- National Comprehensive Cancer Network
www.cancer.gov/clinicaltrials -- Find clinical trials

References

Chan AT, Ogino S, Fuchs CS. Aspirin and the risk of colorectal cancer in relation to the expression of COX-2. N Engl J Med. 2007 May 24;356(21):2131-42.

Cole BF, Baron JA, Sandler RS, Haile RW, Ahnen DJ, Bresalier RS, et al. Folic acid for the prevention of colorectal adenomas: a randomized clinical trial. JAMA. 2007 Jun 6;297(21):2351-9.

Flossmann E, Rothwell PM; British Doctors Aspirin Trial and the UK-TIA AspirinTrial. Effect of aspirin on long-term risk of colorectal cancer: consistent evidencefrom randomised and observational studies. Lancet. 2007 May 12;369(9573):1603-13.

Kerr DJ, Dunn JA, Langman MJ, Smith JL, Midgley RS, Stanley A, et al. Rofecoxib and cardiovascular adverse events in adjuvant treatment of colorectal cancer. N Engl J Med. 2007 Jul 26;357(4):360-9.

Levin TR, Zhao W, Conell C, Seeff LC, Manninen DL, Shapiro JA, Schulman J. Complications of colonoscopy in an integrated health care delivery system. Ann Intern Med. 2006 Dec 19;145(12):880-6.

Meyerhardt JA, Niedzwiecki D, Hollis D, Saltz LB, Hu FB, Mayer RJ, et al. Association of dietary patterns with cancer recurrence and survival in patients with stage III colon cancer. JAMA. 2007 Aug 15;298(7):754-64.

U.S. Preventive Services Task Force. Routine aspirin or nonsteroidal anti-inflammatory drugs for the primary prevention of colorectal cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2007 Mar 6;146(5):361-4.

Veit-Haibach P, Kuehle CA, Beyer T, Stergar H, Kuehl H, Schmidt J, et al. Diagnostic accuracy of colorectal cancer staging with whole-body PET/CT colonography. JAMA. 2006 Dec 6;296(21):2590-600.

Review Date:
9/8/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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adam.com

Weight control and diet

FitSugar — Wed, 08 Oct 2008 17:34:58 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Cancer and Weight Control:

Cancer prevention guidelines from the American Cancer Society stress the importance of maintaining a healthy weight throughout life. A healthy weight is even more important than eating specific healthy foods, when it comes to cancer prevention.

Drug Warning:

The US Food and Drug Administration (FDA) is warning consumers not to buy a product known as the "Brazilian diet pill." This product is labeled as a dietary supplement, but contains several chemicals found in powerful prescription drugs. The products are also known as Emagrece Sim and Herbathin dietary supplements.

New Over-the-Counter Medication:

In February 2007, the FDA approved the first over-the-counter (OTC) weight-loss drug. Orlistat, previously available only by prescription as Xenical, will be available OTC at half its prescription strength. It will be sold under the name alli. Those eager to use the new pill should consider its cost and modest benefits compared with its side effects, most commonly oily diarrhea. This pill, which prevents fat absorption from food, also increases the risk of not absorbing important nutrients from food while using it. The FDA recommends taking a daily multivitamin supplement when using alli.

Research News:

A small study in Norway found that a diet low in fat and high in carbohydrates ("carbs") increases symptoms of psychological distress, such as depression and anger. The study compared three different diets with varying amounts of fat and carbohydrates.
A study released in March 2007 found that obesity in young girls results in early puberty -- as early as age 9.

Effects of Obesity on the Body:

Obesity is associated with certain problems related to infertility, such as uterine fibroids or menstrual irregularities. In men, obesity can contribute to reduced testosterone levels.
People who are obese are at higher risk for carpal tunnel syndrome and other problems involving nerves in their wrists and hands.
The Pickwickian syndrome, named for an overweight character in a Dickens novel, occurs in severe obesity when lack of oxygen produces intense and chronic sleepiness and, eventually, heart failure.

Introduction

A stable weight depends on a good balance between the energy you get from food and the energy you use. You use energy during the day in three ways:

As energy expended during rest (basal metabolism)
As energy used to break down food (thermogenesis)
As energy used during physical activity

Basal metabolism accounts for about two-thirds of spent energy. Your body generally uses this energy to keep your body temperature steady and keep the muscles of your heart and intestine working. Thermogenesis accounts for about 10% of spent energy.

When a person consumes more calories than the energy they use, the body stores the extra calories in fat cells. Fat cells function as energy reservoirs. They enlarge or shrink depending on how people use energy. If people do not balance energy input and output by eating right and exercising, fat can build up. This can lead to weight gain.

When energy input is equal to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person begins to accumulate fat.

Obesity is determined by measuring body fat, not just body weight. People might be over the weight limit for normal standards, but if they are very muscular with low body fat, they are not obese. Others might be normal or underweight, but still have excessive body fat. The following measurements and factors are used to determine whether or not a person is overweight to a degree that threatens their health:

Body mass index (BMI) (a measure of body fat)
Waist circumference (size around the waist)
Waist-hip ratio
Skin fold measurement (anthropometry)
The presence or absence of other disease risk factors (e.g., smoking, high blood pressure, unhealthy cholesterol levels, diabetes, relatives with heart disease)

A person's disease risk factors plus BMI may be the most important components in determining health risks with weight.

The Body Mass Index (BMI). The current standard measurement for obesity is the body mass index (BMI). In general, a BMI of 25 - 29.9 means you are overweight. Obesity is a BMI of 30 and above. Obesity is then classified into three categories:

Class 1: BMI of 30 - 34.9
Class II: BMI 35 - 39.9
Class III: BMI of 40 and greater

These guidelines are very important for people at risk for diabetes, heart disease, or certain cancers. It is also used to determine treatment approaches such as when surgery may be appropriate. The higher the BMI, the greater the risk for significant health problems.

Calculating Body Mass Index (BMI). One's body mass index (BMI) is calculated by multiplying a person's weight in pounds by 703, dividing by the height in inches, and then dividing that number by the height in inches. The steps are as follows:

Multiply one's weight in pounds by 703
Divide that answer by height in inches
Divide that answer again by height in inches

For example, a woman who weighs 150 pounds and is five feet eight inches (or 68 inches) tall has a BMI of 22.8.

Waist Circumference and Waist-Hip Ratio. The extent of abdominal fat can also be used in assessing risk of disease. Some studies suggest that:

Women whose waistlines are over 31.5 inches and men whose waists measure over 37 inches should watch their weight.
A waist size greater than 35 inches in women and 40 inches in men is associated with a higher risk for heart disease, diabetes, and impaired functioning.

Evidence strongly suggests that more body fat around the abdomen and hips (the apple-shape) is a more consistent predictor of heart problems and health risks than BMI.

The distribution of fat can be evaluated by dividing waist size by hip size. For example, a woman with a 30-inch waist and 40-inch hip circumference would have a ratio of 0.75; one with a 41-inch waist and 39-inch hips would have a ratio of 1.05. The lower the ratio the better. The risk of heart disease rises sharply for women with ratios above 0.8 and for men with ratios above 1.0.

Click the icon to see a depiction of the waist-to-hip ratio.

Anthropometry. Anthropometry is the measurement of skin fold thickness in different areas, particularly around the triceps, shoulder blades, and hips. This measurement is useful in determining how much weight is due to muscle or fat.

Biological and Medical Causes

Obesity results when a person consumes more calories than they need for the energy they use. Several different factors may influence weight gain.

About 90% of people who lose weight through dieting gain every pound back regardless of their weight-loss method.

Some evidence suggests that every person has an inherited weight. This range varies by only about 10% either up or down from some set point. For instance, a man whose "genetically-determined" weight is 200 pounds would tend to swing from 180 - 220 pounds. He would be unlikely to lose or gain more than this.

Genetic factors may play some part in 70 - 80% of obesity cases.

Appetite is determined by processes that occur both in the brain and gastrointestinal tract. Eating patterns are controlled by areas in the hypothalamus and pituitary glands (in the brain). The body produces a number of molecules that increases or decreases appetite. In some cases, the following factors may produce imbalances in this process:

Insulin. Insulin is a hormone that helps change blood sugar (glucose) into energy. During digestion, carbohydrates from our diet break down into different types of sugar molecules (including glucose). Proteins from our diet break down into smaller molecules called amino acids. Immediately after eating, blood glucose levels rise. This triggers the release of insulin, which pours into the bloodstream. Insulin pushes the glucose and amino acids into cells and muscles. Insulin and other hormones determine which nutrients will be burned for energy or stored for future use. The inability to use insulin efficiently (insulin resistance) has been associated with both obesity and diabetes.
Leptin. Leptin is a hormone that is released by fat cells. A number of scientists think this hormone may also be released by cells in the stomach. Leptin appears to play an important role in insulin resistance and fat storage in the body, but its role in obesity is unclear. The most likely scenario is that leptin levels rise as the cells store more fat. This increase in leptin levels decreases appetite. Falling levels of leptin make you feel hungry. In people who have genetically lower levels of leptin, however, the brain may be tricked into thinking that it is always starving because there is no leptin to decrease appetite. This can lead to weight gain.
Resistin. Resistin is a hormone produced by fat cells. It makes the body resistant to insulin activity. Some experts believe it may help explain the role of obesity in diabetes type 2.
Intestinal Chemicals. Ghrelin is a chemical produced in the stomach. It appears to be important in triggering the desire to eat. Peptide YY3–36 (PYY) is a substance secreted in the intestines after a meal. The level of PYY is proportionate to the number of calories a person eats. PYY tells the brain that you feel full. Deficiencies in ghrelin and PYY may contribute to some cases of obesity. Researchers are hoping that blocking ghrelin or infusing PYY may be possible treatments for obesity.
Other Chemicals. Many brain chemicals are being studied for their role in appetite stimulation and weight gain. Among them are neuropeptide Y, melanocortins, agouti-related protein, and melanocyte stimulating hormone. Pain-relieving chemicals called endorphins may be critical in reducing appetite and regulating energy use. Cholecystokinin, a hormone released in the upper intestine that stimulates digestive juices, may work to control meal size.

Insulin is a hormone produced by the pancreas that is necessary for cells to be able to use blood sugar.

Genetics may directly contribute to severe obesity in people with family histories of the problem. Genetic factors such as slow metabolisms may also make people more likely to be overweight. At least seven genetic mutations have been associated with specific and uncommon cases of severe obesity. Some are outlined below.

HOB1 (human obesity 1) is a gene that is linked to a high BMI in women.
Leptin gene variants have been linked to leptin deficiencies and obesity.
Melanocortin-4 receptor is a gene that helps turn off the urge to eat. It may not work properly in those with a family history of obesity.
Researchers have also identified a mutation in a gene for a protein called proopiomelanocortin, which results in a syndrome of obesity, red hair, and deficiencies in stress hormones.
A protein called agouti-related protein increases hunger. About 5% of severely obese people have mutations that over-respond to agouti-related protein.

Genetics also determine the number of fat cells a person has. Some people are simply born with more. It should be noted that even when genetic factors are present, a person can still control their diet.

The Thrifty Gene. Some experts think the existence of a so-called "thrifty" gene regulates changes in hormone levels, to accommodate seasonal changes. Theoretically, it works in the following manner:

In certain populations, hormones are released during seasons when food supplies have traditionally been low. This leads to insulin resistance and increased fat storage.
The process is reversed in seasons when food is readily available.
Because modern industrialization has made high carbohydrate and fatty foods available all year long, the gene no longer serves a useful function. Fat, originally stored for famine situations, is not used.

This theory could explain why the previously nomadic Native American tribes who now have Western dietary habits have such high rates of Type 2 diabetes and obesity. In the past, the traditional low-fat, high-fiber foods tribe members ate may have protected them from obesity and type 2 diabetes. Today, these tribes' diet consists of more Western foods, which are higher in fat. Furthermore, these foods are readily available year-round, and many members of the tribe are sedentary. The result is a very high incidence of Type 2 diabetes and obesity. Although genetic abnormalities may make it harder or easier to lose weight, the occurrence of obesity has dramatically increased over the past two decades, and genes cannot have changed within that short amount of time. Our ability to use the food that we eat evolved so that our body could conserve energy and store fat during times of famine. Most cases of obesity now occur in people with normal body function who live in industrialized nations, where there is more than enough food.

A number of medical conditions may contribute to being overweight, but rarely are they a primary cause of obesity.

Hypothyroidism is sometimes associated with weight gain. But, patients with an underactive thyroid generally show only a moderate weight increase of five to 10 pounds.
Very rare genetic disorders, including Froehlich's syndrome in boys, Laurence-Moon-Biedl, and the Prader-Willi syndromes, cause obesity.
Abnormalities or injury to the hypothalamus gland can cause hypothalamic obesity.
Cushing's disease is a rare condition caused by high levels of steroid hormones. It results in obesity, a moon-shaped face, and muscle wasting.
Obesity is also linked to polycystic ovarian syndrome, a hormonal disorder in women.

Click the icon to see an image of polycystic ovaries.

Some prescription medications contribute to weight gain, usually by increasing appetite. Such drugs include the following:

Corticosteroids
Female hormone treatments, including some oral birth control pills (effect is usually temporary), and certain progestins (such as Megestrol) used to treat cancer
Antidepressants and anti-psychotic drugs, including lithium and valproate
Insulin and insulin-stimulating drugs used to treat diabetes often lead to weight gain, a particularly unfortunate conflict of interest for obese individuals with type 2 diabetes

You should not stop taking any medications without your doctor's knowledge.

Cultural and Emotional Causes

Enough food is produced in the US to supply 3,800 calories every day to each man, woman, and child in the country, far more than the average person needs to sustain life. In a 2002 study, participants carefully recorded everything they ate and drank, and all activities and psychological factors surrounding the eating events. The people who gained weight ate more and their portions were larger than those who did not. This may be an obvious conclusion, but the public press often plays up biologic factors involved with obesity and overlooks the simple notion that Americans eat too much and exercise too little.

Obesity is dramatically increasing not only in American children and adults, but also in every country that has adopted similar cultural habits. The World Health Organization now considers obesity to be a global epidemic and a public health problem as more nations become "Westernized." In spite of the proven health risks of obesity, the government, insurance companies, and the medical profession do not spend nearly enough money to balance the commercial and cultural pressures that are producing millions of overweight people.

In 2007, the Robert Wood Johnson Foundation sounded a positive note with the announcement of a $500 million initiative, aimed at “reversing the childhood obesity epidemic by 2015.” The money will be used for research, education, and activities that promote healthy eating among America’s children.

Perhaps the primary reason for the dramatic rise in obesity is the sedentary (inactive) lives led by most Americans, including children and young people. In a 2003 study comparing modern life to the past, researchers found that labor saving devices had reduced a person's energy use by 111 calories a day -- adding up to an extra 11 pounds a year. Half the difference in energy use was due to less walking. At the same time, according to the U.S. Centers for Disease Control and Prevention, between 1970 and 2000 the typical American man increased his caloric intake by 168 calories a day (good for 17 pounds a year) while the average woman added 335 calories a day.

Regular television watching has been singled as the most hazardous pastime. According to a major 2003 study, for every 2 hours a person spends in front of the TV each day, the risk for obesity increases by 23% and for type 2 diabetes by 14%. In the study, TV watching produced the lowest metabolic rates compared to sewing, playing board games, reading, writing, and driving a car. Just the act of watching TV encourages unhealthy snacks and eating patterns. In addition, the advertising on the television complicates the problem by promoting fast foods, cereal, and snack products that are high in salt, fats, and carbohydrates. Even worse, much of these advertisements are directed at children -- the most vulnerable group.

People are not only eating more food than they did 20 years ago, they are also replacing home cooking with packaged foods, fast food, and dining out. This behavior, according to studies, places people at higher risk for obesity. Fast foods may be more harmful than restaurant cooking. These foods tend to be served in larger portions. They generally contain more calories and unhealthy fats, and less nutritious ingredients, than homemade or restaurant meals. Snack foods and sweet beverages, including juice and soft drinks, are specific problems that add to the increasing rates of obesity. Frequent small, healthy meals (instead of two or three large daily meals) have been associated with lower weights.

People react differently to stress. Some overeat and gain weight and others stop eating and lose weight. People who gain weight in response to stress often overeat foods high in sugar, fats, and salt. A 2003 study on rats suggested that stress hormones increase the pleasure of eating such so-called "comfort foods." Furthermore, the study supported previous research showing that stress-related eating was connected to the unhealthy accumulation of abdominal fat.

Risk Factors

Where you live plays a role in your risk for obesity. Simply living in the United States makes a person more susceptible to obesity. The prevalence of obesity in America has risen dramatically over the past few years and continues to increase.

According to the latest figures available, 32.2% of American adults (aged 20 and older) are obese (BMI over 30) -- up from about 23% in the early 1990s.
The number of Americans aged 20 - 74 who were overweight also increased -- from about 44.8% in 1960 to 65.2% in 2002.
The rate of extreme obesity (BMI > 40) increased from 0.8% in 1960 to 4.9% in 2002.
Obesity has increased in every state, in both men and women, across all age groups, and in every ethnic group, although some groups may face slightly higher risks than others.

Fat tends to settle in certain regions, depending on gender. Women gain fat predominantly in the stomach, hips and thighs, while men tend to gain fat in the belly and waist.

Risk by Age. People of any age are at risk for obesity. More children and adolescents are overweight in America than ever before. Gaining some weight is inevitable with age and adding about 10 pounds to a normal base weight over time is not harmful. The current weight gain in American adults over 50, however, is significant. By age 55, the average American has added nearly 40 pounds of fat during the course of adulthood. This condition is made worse by the fact that muscle and bone mass decrease with age.

Risk by Gender. In men, BMI tends to increase until age 50 and then it levels off. In women, weight tends to increase until age 70 before it plateaus. A 2000 study found that there are three high-risk periods for weight gain in women.

The first is at the onset of menstruation, particularly if it is early. In fact, a study released in March 2007 found that obesity in young girls results in early puberty -- as early as age 9. This, in turn, increases the risk for more weight gain as girls enter puberty.
The second is after pregnancy, with higher risk for women who are already overweight.
Finally, many women gain weight after menopause.

These findings are significant because they may allow women to target high-risk times, and consequently prevent unnecessary weight gain.

Risk by Economic Group. Obesity is more prevalent in lower economic groups. One 2002 study reported that women who reported that they did not have enough food were more likely to be overweight than those who said they had sufficient food. Researchers discovered that the low-income women tended to have fewer fruits and vegetables but were actually taking in more calories a day than higher-income women. However, obesity is increasing in young adults with college education as well as in other groups.

Ethnic Groups. Among ethnic groups in general, African-American women are more overweight than Caucasian women but African-American men are less obese than Caucasian men. (Currently, 80% of African-American women are overweight.) Hispanic men and women tend to weigh more than Caucasians.

US Regions. Regionally, the prevalence of obesity is lowest in the Western states and highest in the South.

A number of dietary habits put people at risk for becoming overweight:

Night-Eating Syndrome. Night-eating syndrome is defined as having no appetite in the morning, insomnia, and consuming more than half of daily food intake after 6:00 PM. It is associated with obesity and is difficult to treat. Stress reduction and relaxation techniques may be helpful.
Binge Eating and Eating Disorders. About 30% of people who are obese are binge eaters who typically consume 5,000 - 15,000 calories in one sitting. To be diagnosed as a binge eater, a person has to binge at least twice a week for 6 months. Many experts believe that binge-eating carbohydrates causes an increase in a natural opiate leading to dependence on carbohydrates. Therefore, this condition should be treated as an addiction. Other eating disorders are bulimia and anorexia. Bulimia is binge eating followed by purging in order to lose weight. Anorexia nervosa is a mental illness in which the person refuses to maintain weight at the normal level. The patient with anorexia has a terrible fear of getting fat, and an abnormal perception of what his or her body looks like. Both conditions pose risks for serious medical problems, and anorexia nervosa can be life-threatening. A combined approach using behavioral therapy and antidepressants may help these individuals. [See In-Depth Report #49: Eating disorders.]
Restrained Eating. Some people, mostly middle-aged women who have normal weight, have a pattern referred to as restrained eating. This pattern requires a high level of conscious control and usually maintains a lower weight. However, such restraint places these individuals at higher risk for loss of control and subsequent overeating.
Infrequent Eating. There is some evidence to suggest that eating small frequent meals uses more calories than infrequent large meals. It should be strongly noted, however, that packaged snack foods add calories and some do not produce a feeling of being full, so that people simply eat more than they should.

Anyone with Sedentary Lifestyles. Office workers, drivers, and anyone whose lifestyle involves sitting for long periods are at higher risk for obesity.

Ex-Smokers. The trend toward weight increase has followed the trend for quitting smoking. Nicotine increases the metabolic rate, and quitting, even without eating more, can cause weight gain, which may be considerable. It is important to note that weight control is not a valid reason to smoke. People in previous centuries did not smoke cigarettes, nor were they usually obese.

Shift-Workers. A recent study found that individuals who work late shifts (between 4 p.m. and 8 a.m.) tend to eat more and take longer naps than day workers and are more likely to gain excess weight.

People with Disabilities. Obesity rates are higher than average in people with physical or mental disabilities. Those with disabilities in the lower part of the body, such as the legs, are at highest risk.

Overweight in children and adolescents is rising at an alarming rate. In 2004, 19% of young children aged 6 - 11 were overweight, an increase of 8% from 1994. Among children aged 25, 13.9% were overweight in 2004, up from 7.2% 10 years earlier.

Definition of Overweight in Children

Children and adolescents are considered to be overweight if their BMI is above 95% of the children in their age and sex categories. Ethnic variations, timing of growth spurts, and higher normal fat levels around puberty can affect these measurements.

Causes and Risk Factors for Overweight in Children

Lifestyle Factors. Without educational or parental guidance, children are extremely vulnerable to the intense cultural pressures that are largely responsible for the obesity epidemic. The following are some specific problems created by the culture:

Excessive television watching plays a critical role in obesity in children. Not only is it a sedentary activity, but television also offers innumerable temptations with its advertisements for fast foods, sugar cereals, and unhealthy snacks. In one study obesity rates were lowest in children who watched television 1 hour or less a day and highest in those who watched 4 or more hours.
Sugar, particularly from soda, other sweetened beverages, and fruit juice, may be the major contributor to childhood obesity. One study reported that drinking soda regularly increases a child's risk for obesity by 60%. The average American adolescent consumes 15 - 20 extra teaspoons of sugar a day just from soda and sugary drinks. (Juice, while better than soda, is still filled with sugar.)
Less physical exercise and greater sedentary activities play another significant role in obesity in children. A high level of physical activity -- not just using up energy -- is important for weight control in young people. Unfortunately, according to one study, the annual distance walked by children has fallen by nearly 30% since 1972, partially because more parents are driving their children to school out of fear of abduction, molestation, and traffic accidents. Schools are also offering fewer opportunities for daily physical activities than in the past.

Neither the media nor the educational system has strong well-financed programs that encourage healthy alternatives, including exercise and healthy foods.

Family History. Parental obesity more than doubles the risk that a young child, whether thin or overweight, will become obese as an adult. In older children and teenagers, obesity in parents starts to count less as a predictor for body weight than their own weight. The risk for obesity may be due to environmental or genetic factors, or both.

Ethnic and Socioeconomic Factors. As in adult populations, children from lower socioeconomic groups and minority populations are at higher risk for obesity. For example, among young Mexican Americans and African-Americans, there has been an increase in overweight prevalence of about 13% to over 23%.

Factors Surrounding Birth. The following factors surrounding birth are associated with a child's weight:

Low birth weight is a risk factor for later obesity and diabetes. One theory is that humans have a "thrifty gene" that produces metabolic changes in infants with low birth weight. Such changes affect insulin and fat accumulation, in order to produce a "catch-up" weight in these young children as quickly as possible. This rapid weight gain in infancy increases the risk for obesity in children and young adults.
In a study of African-American children, having an overweight pregnant mother increased the risk for later weight gain, but low birth weight did not.

Although some small studies have reported protection against obesity from breastfeeding, evidence is weak. In a 2003 study, for example, children who were breast fed for 3 - 5 months had a lower risk for obesity, but prolonged breastfeeding had no effect. Nevertheless, given the healthful effects of breast feeding and the possibility that it may have even a slight impact on childhood obesity, it is highly recommended.

Biological Effect of Childhood Overweight on Adult Weight

Achieving a healthy weight becomes more difficult as children get older. The odds of obesity persisting into adulthood ranges from 20% in 4 year olds to 80% in teenagers. One reason for the persistence is biological. The fat cells change in number or mass depending on a person's age:

Fat cells themselves multiply during two growth periods: early childhood and adolescence. Overeating during those times increases the number of fat cells. Some people are also just born with more fat cells.
After adolescence, fat cells tend to increase in mass rather than quantity, so that adults who overeat and gain weight tend to have larger fat cells, not more of them. This growth in mass may be responsible for the greater risk of persistent obesity among teenagers compared to small children who are overweight. Losing weight after adolescence reduces the size of the fat cells but not their number, so weight loss becomes much more difficult.

Health Consequences of Childhood Overweight

Children and adolescents who are overweight have poorer health than other children. Studies are reporting unhealthy cholesterol levels and high blood pressure in overweight children and adolescents. Of great concern is the dramatic increase in type 2 diabetes in young people, which is largely due to the increase in overweight children. Overweight in children is also linked to asthma, gallbladder problems, sleep apnea, and liver abnormalities. Overweight girls are more likely to enter puberty early, according to a new study, and subsequently be at higher risk for breast cancer.

It is not clear yet how many of these childhood problems persist in people who achieve normal weight as adults. Staying overweight into adulthood certainly carries health risks.

Managing Overweight Children

Childhood obesity is best treated by a non-drug, multidisciplinary approach including diet, behavior modification, and exercise. Evidence suggests that reducing calories by only 200 - 260 per day would prevent weight gain in most overweight children. Here some tips for children who are overweight:

Limit (or avoid, if possible) take out, fast foods, high-sugar snacks, commercial packaged snacks, soda, and sugar-sweetened beverages (including too much juice).
Let children snack but make sure the snacks are healthy. Eating small frequent healthy meals (instead of two or three large ones) has been associated with being thinner and having a better cholesterol profile.
Let children choose their own food portions. One study indicated that children naturally ate 25% less when they chose their own portion size. When they were given larger portions their bite sizes were larger and they ate more.
Do not criticize a child for being overweight. It does not help and such attitudes could put children at risk for eating disorders, which are equal or even greater dangers to their health.
Limit television, video games, and computer use to a few hours a week. This can contribute significantly to weight control, regardless of diet and physical activity.
For young children, try the traffic-light diet. Food is designated with stoplight colors depending on their high caloric content: Green for go (low calories); yellow for "eat with caution" (medium calories); red for "stop" (high calories).
Try a low glycemic index diet. This may be as beneficial, and possibly more, than a standard reduced-fat diet in overweight children. Such a diet focuses on certain carbohydrates (for example, dried beans and soy), which raise blood sugar more slowly than other types of carbohydrates. This diet is sometimes used in diabetes, and as a dietary approach in overweight adults. [See In-Depth Report #42: Diabetes diet.]

Click the icon to see an image about TV watching.

Click the icon to see an image of childhood overweight.

Complications

General Adverse Effects of Obesity. Obesity, defined as a BMI of 30 or over, accounts for nearly 300,000 deaths in the U.S. each year. It is associated with more chronic health problems than smoking, heavy drinking, or poverty. Furthermore, given the current increase in obesity, it will surpass smoking as the most important preventable cause of death in America.

Some studies indicate the following health risks by body mass:

The lowest risks for heart disease, diabetes, and some cancers are in people with BMI values of 21 - 25.
The risks increase slightly when BMI values are between 25 - 27.
The risks are significant in BMIs between 27 - 30.
The same risks are dramatic at BMIs over 30.

Anyone with chronic health problems such as heart or lung disease, stroke, or arthritis, should be concerned about extra weight. This same concern also applies to people with known risk factors for such conditions.

Metabolic Changes. As fat stores increase, the fat cells themselves enlarge and produce chemicals that increase the risk for several diseases. Such diseases may include diabetes, high blood pressure, gallbladder disease, and some cancers.
Increased Mass. The increased body weight itself causes problems that result in injury and diseases, including osteoarthritis and sleep apnea.
Harmful Fat Cell Types. Weight concentrated around the abdomen and in the upper part of the body (the apple shape) poses a higher health risk than fat that settles around the hips and flank (the pear shape). Fat cells in the upper part of the body appear to have different qualities from those found in the lower parts. In fact, studies suggest a higher risk for diabetes in people with the "apple shape" and lower risk in those who are "pear shaped."

Weight gain in the area of and above the waist (apple type) is more dangerous than weight gained around the hips and flank area (pear type). Fat cells in the upper body have different qualities than those found in hips and thighs.

General Adverse Effects of Being Overweight (Not Obese). It is still not clear if being overweight (a BMI of 25 - 29.9) hurts healthy people with no risk factors for serious illnesses.

According to one 2001 study, just being overweight increased the risk for developing diabetes, gallstones, hypertension, heart disease, stroke, and colon cancer. The risk rose according to how much the individuals were overweight. In any case, adults who are overweight in middle age face a poor quality of life as they age, with the quality declining the greater the weight. One study suggested, however, that being over 65 and overweight (but not obese) is not associated with higher mortality rates.

Some experts argue, in fact, that in anyone who is not severely obese, it is the unhealthy diet and sedentary lifestyle that causes harm -- not weight per se. In support of this argument, a British study found that overweight fit individuals had half the death rate of unfit trim individuals.

Being somewhat overweight may also have some benefits under specific circumstances:

In older women, some excess fat may produce extra estrogen that helps slow down bone loss, and insulates bones from fall-related injuries. It should be strongly noted, however, that when older overweight women lose weight they report less pain, improved vitality, and improved physical function. The same positive effect of overweight does not appear to hold in older men.
Conditioned athletes may have high BMIs because of very dense muscle tissue. Being fit in general may protect many overweight people.
Some evidence suggests that Caucasians have the lowest mortality with BMIs of 24.3 - 24.7 while African-Americans are better off in the range of 26.8 - 27.1.
Children may have higher normal fat levels during growth spurts and around puberty.

Individuals with a BMI of at least 30 have a 10 - 50% increased rate of death from all causes, compared with individuals with a BMI of 20 - 25. Mortality rates from many causes are higher in obese people, but heart disease is the primary cause of death. People who are obese have almost three times the risk for heart disease as people with normal weights. Being physically unfit adds to the risk.

Weight concentrated around the abdomen and in the upper part of the body (apple shape) is particularly associated with insulin resistance and diabetes, heart disease, high blood pressure, stroke, and unhealthy cholesterol levels. Fat that settles in a pear shape around the hips and lower body appears to have a lower association with these conditions.

Obesity poses many dangers to the heart and circulatory system.

Damage in the Blood Vessels. As people age, changes in body fat (particularly increasing abdominal fat) seem to cause stiffness in the aorta, the major blood vessel leading from the heart. Studies are finding higher levels of a factor called C-reactive protein (CRP) in people with obesity and abdominal fat. CRP is now considered to be a marker for inflammation and damage in the arteries. (Losing weight reduces CRP levels.)

High Blood Pressure. High blood pressure is the health problem most commonly associated with obesity, and the greater the weight, the greater the risk. High blood pressure carries serious risks of stroke, heart attack, and heart failure. The link between obesity and high blood pressure is complex, and may be a combination of genetic, population, and biological factors. Many studies have reported that modest weight loss is beneficial for reducing existing high blood pressure. [See In-Depth Report #14: High blood pressure.]

Heart Failure. An important 2002 study reported that obesity might account for 11% of heart failure cases in men and 14% in women. This link existed independently of other risk factors, such as high blood pressure, sleep apnea, and diabetes, which are also associated with obesity. The biologic mechanisms involved in obesity that lead specifically to heart failure are not clear. [See In-Depth Report #13: Heart failure.]

Unhealthy Cholesterol Levels and Lipid Levels. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels (the major form of fat storage in the body) are usually high, while HDL levels (the "good" cholesterol) tend to be low. Both conditions are risk factors for heart disease. [See In-Depth Report #23: Cholesterol.]

Click the icon to see an image of coronary artery disease.

Stroke. Obesity is also associated with a higher risk for stroke. [See In-Depth Report #45: Stroke.]

Type 2 Diabetes and Insulin Resistance. Most people with type 2 diabetes are obese and, in fact, studies strongly suggest that weight loss may be the key in controlling the current epidemic of type 2 diabetes. The common factor appears to be insulin resistance. Insulin is a critical hormone in the use of sugar. In type 2 diabetes, different factors cause the body to become insulin resistant -- that is, the body can no longer respond properly to insulin. This has the effect of increasing sugar levels in the blood, the hallmark of diabetes. Both obesity and insulin resistance, at different phases, are marked by high levels of certain chemicals. It is not known yet if the higher levels are simply a product of obesity, or play some role in causing diabetes.

Insulin resistance is also associated with high blood pressure and abnormalities in blood clotting. Some research indicates that obesity, in fact, is the one common element linking insulin resistance, diabetes type 2, and high blood pressure. [See In-Depth Report #60: Diabetes - type 2.]

Metabolic Syndrome. Metabolic syndrome (also called syndrome X) is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. The syndrome consists of obesity marked by abdominal fat, unhealthy cholesterol levels, high blood pressure, and insulin resistance. A 2002 study estimated that nearly a quarter of the U.S. population now has this condition. Even worse, according to a 2003 study, nearly a million American teenagers have this syndrome. A combination of weight loss and exercise is an effective treatment for this syndrome.

The American Cancer Society released new cancer prevention guidelines in September 2006. The guidelines stress the importance of keeping a healthy weight throughout life. The Society indicates that healthy weight is even more important than eating specific healthy foods, when it comes to cancer prevention.

Obesity has been associated with a higher risk for cancer in general and specific cancers in particular. Studies have also suggested that restricting calories reduces the risk for cancer. Some experts believe that effective weight control for children and adults could reduce cancer rates by 30 - 40%. One way obesity may increase the risk for cancer is its association with high levels of hormones called growth factors, which can trigger rapid cell production leading to cancer.

Uterine Cancers. The risk of uterine cancer in obese women appears to be two or three times higher than in thinner women.

Prostate Cancer. New studies from 2005 and 2006 report that obesity is associated with an increase in prostate cancer mortality, although not with the risk for less aggressive forms of prostate cancer.

Click the icon to see an image of prostate cancer.

Breast Cancer. Studies are mixed on the association between obesity and breast cancer. A number of studies have linked obesity to breast cancer in postmenopausal women, particularly in women who begin to gain weight after age 18.

Click the icon to see an illustrated series detailing a breast cancer surgery (mastectomy).

Gallbladder Cancer. Obese women are at higher risk for gallbladder cancer.

Gastrointestinal Cancers. A number of cancers in the gastrointestinal tract have been associated with obesity:

Cancer of the esophagus may be due to a higher incidence of gastroesophageal reflux disorder (heartburn) in people who are overweight.
Colon cancer has been linked to increased body mass in both men and women.
Pancreatic cancer and obesity have been weakly linked, with one study reporting a lower risk in overweight people who are physically active.

Click the icon to see an illustrated series detailing a colon cancer surgery.

Muscles and Bones

Obesity places stress on bones and muscles. Studies report that the incidence of osteoarthritis is significantly increased in people who are overweight. People who are obese are also at higher risk for carpal tunnel syndrome and other problems involving nerves in their wrists and hands. It should be noted that some weight may be protective against osteoporosis (loss of bone thickness).

Obesity increases the risk for the following mouth and eye disorders:

Gum disease
Cataracts
Maculopathy, an eye disease related to aging

Infertility. Abnormal amounts of body fat, either 10 - 15% too high or too low, can contribute to infertility in women. Obesity is specially related to certain infertility problems, such as uterine fibroids or menstrual irregularities. In men, obesity can contribute to reduced testosterone levels.

Effect on Pregnancy. Obesity has many dangerous effects on pregnancy. These include high blood pressure, gestational diabetes (diabetes, usually temporary, that occurs during pregnancy), urinary tract infections, blood clots, prolonged labor, and higher fetal death rate in late stages of pregnancy. Obesity is also associated with increased rates of cesarean delivery. Infants of women who are obese are also at higher risk for neural tube birth defects, which affect the brain or spine. Folic acid supplements, ordinarily effective in preventing these conditions, may not be as protective in overweight women.

Obesity is thought to be a risk factor for symptoms of adult-onset asthma. Though there is evidence that obesity causes wheezing and shortness of breath, it does not appear to be strongly associated with the disease mechanisms in the lungs that cause true asthma.

Obesity also puts people at risk for hypoxia, a condition in which there is not enough oxygen to meet the body's needs. Obese people need to work harder to breathe. They tend to have breathing muscles and lungs that do not work as well as those in thinner people.

The Pickwickian syndrome, named for an overweight character in a Dickens novel, occurs in severe obesity when lack of oxygen produces intense and chronic sleepiness and, eventually, heart failure.

Nonalcoholic Fatty Liver Disease. People with obesity, particularly if they also have type 2 diabetes, are at higher risk for a condition called nonalcoholic fatty liver disease, also called nonalcoholic steatohepatitis (NASH). This condition causes liver damage that is similar to liver injury seen in alcoholism. In some cases, it can be very serious and require liver transplantation. It occurs in about half of people with diabetes, and 20 - 50% of obese people, depending on how severe their obesity is. NASH can also occur in overweight children.

Gallstones. The incidence of gallstones is significantly higher in obese women and men. The risk for stone formation is also high if a person loses weight too quickly. In people on ultra-low calorie diets, gallstones may be prevented by taking ursodeoxycholic acid (Actigall).

Click the icon to see an image of gallstones.

People who are obese and nap tend to fall asleep faster and sleep longer during the day. At night, however, it takes them longer to fall asleep, and they sleep less than people with normal weights. In an apparent vicious circle, studies have suggested that obesity not only interferes with sleep but that sleep problems may actually contribute to obesity.

Sleep Apnea. Obesity, particularly the apple shape, is strongly associated with sleep apnea, which occurs when the upper throat relaxes and collapses from time to time during sleep. This collapse temporarily blocks the passage of air. Sleep apnea is increasingly being viewed as a potentially serious health problem, which may lead to complications such as heart disease and stroke. Some studies suggest that among overweight people, those who have sleep apnea have a greater risk of heart disease than those without it. In one study, the more obese a person with sleep apnea was, the higher the pressure on the airway, and therefore the greater the obstruction of the airway. Obstructive sleep apnea may also add to obesity, however, as sleepy people tend to be sedentary. Some studies indicate that treating sleep apnea may help people lose abdominal fat.

Narcolepsy. A small European study found a link between narcolepsy (a sleep disorder characterized by excessive daytime sleepiness with frequent daily sleep attacks) and high BMI.

Depression. A number of studies have reported an association between depression and obesity, particularly in obese women. There may be a number of factors to explain the link. In some cases of atypical depression, people overeat and may gain weight. Overweight people may also become depressed because of social problems and a poor self-image. In these cases, depression usually disappears when people lose weight.

There is evidence, however, that obesity itself may impair levels of tryptophan -- a chemical needed to make serotonin, a brain chemical associated with mental well-being. In one study, even after people lost weight, tryptophan levels were lower than normal.

There does not appear to be any association between depression and obesity in men.

Social Problems. One long-term study reported that overweight young women completed fewer years of school, were 20% less likely to be married, and had 10% higher rates of household poverty than their thinner peer. Obese young men were also less likely to be married, and their incomes were lower than their thinner peers. Nevertheless, studies consistently show that overweight males (both boys and men) are not as severely emotionally affected as females of any age. Women and girls tend to blame themselves for being heavy, while males tend to blame being overweight on outside factors.

Weight Loss and Maintenance

Even modest weight loss can reduce the risk factors for heart disease and diabetes. The simplest (but still difficult) approach to weight loss is reducing calories and exercising at least 150 minutes a week. Behavioral and mental changes in eating habits, physical activity, and attitudes about food and weight are also essential to weight management. For people who are very overweight and cannot lose weight through lifestyle changes, a number of effective weight-loss medications are available. For those with severe obesity, surgical procedures are proving to be very beneficial.

Some Tips for Losing Weight. The following are some general suggestions for dieters:

Start with realistic goals. Diet failure is extremely common, and the odds of significant weight loss are low, particularly in people with the highest weights. People who are able to restrict calories, engage in an exercise program, and get help in making behavioral changes can expect to lose between 5 - 10% of their current body weight. That is generally all that is needed to achieve meaningful health changes. Certainly, the distorted image of a super-thin female shape should not be anyone's goal.
Maintain a regular exercise program, assuming you have no health problems that will stop you. Choose a program that you enjoy. Check with your doctor about any health considerations. [See In-Depth Report #29: Exercise.]
Do not use hunger pangs as cues to eat. A stomach that has been stretched by large meals will continue to signal hunger for large amounts of food until its size reduces over time with smaller meals.
Be honest about how much you eat and start by recording all calories in writing. Studies suggest that when many people report their own calories intake they significantly underestimate their consumption of high-calorie and over-estimate the low-calorie foods. People who do not carefully note everything they eat tend to take in too many calories when they believe they are dieting.
Observe weekend eating. People tend to eat more on the weekends. If it is difficult to monitor all meals during the week, it be may be useful to at least track eating habits during the weekends.
Once the pounds are lost, do your best to keep the healthier weight. Make daily, even hourly, conscious decisions about eating and exercising activities. Such thinking, in many cases, can become automatic and not painful.
Don't give up, even after repeated weight loss failures. Most studies indicate that yo-yo dieting or weight cycling have no bad psychological or physical effects. Repeated dieting also does not harm the body's ability to burn calories efficiently.
Weight loss, in any case, should not be the only or even the primary goal for people concerned about their health. The success of weight loss efforts should be evaluated according to improvements in disease risk factors or symptoms, and by the adoption of healthy lifestyle habits, not just by the number of pounds lost.


Lifestyle	Reduce rate of eating. Keep food records. Eliminate environmental triggers to eating. Identify high-risk situations for overeating. Separate eating from other activities.
Exercise	Face up to emotional barriers to exercise. Understand the link between exercise and weight control. Establish reasonable exercise goals. Develop a plan for regular activity. Add increased activity into daily lifestyle.
Attitudes	Develop reasonable weight-loss goals. Avoid "all or none" thinking. Focus attention away from the scale and toward behavior. Uncouple weight from self-esteem. If you "fall off the wagon," take steps to ensure the situation does not repeat (recover from lapses with constructive action).
Relationships	Understand the key role of social support to health. Identify supportive others. Match personal style to support-seeking activities. Be specific in making support requests. Be assertive but reinforcing in drawing help from others.
Nutrition	Resist the temptation of popular fad diets. Eat with your health in mind; do not concentrate on what should be "off-limits." Eat with moderation in mind. Maximize fiber. Develop a tailored plan.
From Brownell KD. The LEARN Program for Weight Control. 7th ed. Dallas, Tex: American Health Publishing Company; 1998.

Weight Management

There are many approaches to dieting and many claims for great success with various fad diets. To date, although many diets achieve effective immediate weight loss, none has emerged as an effective tool for maintaining healthy weight. The only definite recommendation that can be made about any diet plan is to be sure it includes an exercise program, assuming there are no health problems to forbid it.

The original food pyramid, with four food groups, has been replaced with an updated food guide called "My Pyramid." This illustrates the relative proportions of different foods that make up a nutritious, well-balanced diet and includes exercise.

Calorie restriction has been the cornerstone of obesity treatment. The standard dietary recommendations for losing weight are the following:

As a rough rule of thumb, one pound of fat equals about 3,500 calories. A person could lose a pound a week by reducing daily caloric intake by about 500 calories a day. Naturally, the more severe the daily calorie restriction, the faster the weight loss. Very-low calorie diets have also been associated with better success, but extreme diets can have some serious health consequences.
To determine your daily calories requirements, multiply the number of pounds of ideal weight by 12 - 15 calories. The number of calories per pound depends on gender, age, and activity levels. For instance, a 50-year old woman who wants to maintain a weight of 135 pounds and is mildly active might require only 12 calories per pound (1,620 calories a day). A 25-year old female athlete who wants to maintain the same weight might require 25 calories per pound 2,025 (calories a day).
Fat intake should be no more than 30% of total calories. Most fats should be in the form of monounsaturated fats (such as olive oil). Saturated fats (found in animal products) should be avoided.

Extreme diets of less than 1,100 calories carry health risks. They are also often followed by bingeing or overeating, and a return to the obese state. Such diets often do not have enough vitamins and minerals, which must then be taken as supplements. Most of the initial weight loss is in fluids. Later, fat is lost, but so is muscle, which can account for more than 30% of the weight loss. No one should be on severe diets for longer than 16 weeks, or fast for more than 2 or 3 days. Severe dieting has unpleasant side effects including fatigue, intolerance to cold, hair loss, gallstone formation, and menstrual irregularities. There have been rare reports of death from heart arrhythmias when liquid formulas did not have sufficient nutrients. Pregnant women who excessively diet during the first trimester put their unborn children at risk for birth defects. Of note, those whose diets include a high intake of fluids and much reduced protein and sodium are at risk for hyponatremia, which can cause fatigue, confusion, dizziness, and in extreme cases, coma and death.

This dietary approach requires counting only grams of fat with the goal of achieving 30% or fewer calories from fat. One gram of fat contains nine calories, while one gram of carbohydrates or protein has only four calories. Fat in your diet converts more readily to fat in the body, compared with carbohydrates or proteins. Simply switching to low-fat or skimmed dairy products may be enough for some people.

There are possible drawbacks to this approach:

Some people who reduce their fat intake may not get enough basic nutrients, including vitamins A and E, folic acid, calcium, iron, and zinc. People on low-fat diets should eat a wide variety of foods and take a multivitamin supplement, if appropriate. Calcium deficiencies may be particularly harmful in women at risk for osteoporosis.
Many people start eating foods with too many carbohydrates, believing that they are not adding calories. No one should use a low-fat diet as an excuse for eating too many carbohydrates, particularly starchy foods and sugar. A high-calorie diet from any source will add pounds.
A small study in Norway found that a diet low in fat and high in carbohydrates ("carbs") increases symptoms of psychological distress, such as depression and anger. The study compared three different diets that had varying amounts of fat and carbohydrates in each. The diets contained the same amount of calories, but differed in the percentage and type of fat. People on the low-fat, high-carbohydrate diet reported more anger and depression compared with the other two diets.
Replacing fatty foods, such as cakes, cookies, and chips, with their commercial "low-fat" counterparts does not constitute a low-fat diet. These foods generally contain more sugar and hence calories, not to mention other ingredients, which have virtually no nutritional value. In fact, a 2002 study suggested that increasing sugar may, over time, reduce levels of HDL ("good") cholesterol.
Very low-fat diets may increase the risk for stroke from hemorrhage in the brain.

Some fat in a diet is essential. It should come from plant oils and fish, however, and not from animal products or hardened oils, such as margarine. Trans-fatty acids, found in hardened oils, are actually more of a risk factor for obesity than saturated fats from animal products, although both should be avoided.

Fiber and Complex Carbohydrates. In all cases, complex carbohydrates found in whole grains and vegetables are preferred over those found in starch-heavy foods, such as pastas, white-flour products, and potatoes. Fiber is an important component of many complex carbohydrates. Fiber is almost always found only in plants, particularly vegetables, fruits, whole grains, nuts, and legumes (beans and peas). One exception is chitosan, a dietary fiber made from shellfish skeletons. Fiber cannot be digested but passes through the intestines, drawing water with it, and is eliminated as part of feces content. The following are specific advantages from high-fiber diets (up to 55 grams a day):

Insoluble fiber (found in wheat bran, whole grains, seeds, nuts, and fruit and vegetable peels) has been associated with weight loss. Studies also suggest that diets rich in fiber from whole grains reduce the risk for type 2 diabetes.
Soluble fiber (found in dried beans, oat bran, barley, apples, citrus fruits, and potatoes) has important benefits for the heart, particularly for achieving healthy cholesterol levels and possibly benefiting blood pressure as well. Simply adding breakfast cereal to a diet appears to reduce cholesterol levels. People who increase their levels of soluble fiber should also increase water and fluid intake.

High-protein, low carbohydrate diets, such as the Atkins and South Beach diets, have been touted as effective ways to produce short-term weight loss. Because of their emphasis on fats and proteins, many experts are concerned about long-term health problems. A report in the March 2006 Lancet linked the Atkins diet to life-threatening complications that caused the death of one woman. The 40-year-old woman had a deadly buildup of acids called ketones in her blood, a condition called ketoacidosis. Ketoacidosis can cause coma and death. Ketones are a known by-product of high protein, low carbohydrate diets. At low levels they can cause nausea, lightheadedness, and bad breath.

The long-term effects of these diets are still unknown. For example, the Atkins diet restricts some vegetables and most fruits, which are known to protect against serious diseases such as heart problems and cancer. The diet may also cause too much calcium to build up in the urine. This can increase the risk for kidney stones and osteoporosis. In addition, high-protein intake, particularly from meat, can be harmful in people with kidney problems. Individuals at risk for kidney stones, or those who have other kidney problems, should not go on high-protein diets without talking to their doctor first. Unfortunately, many people with diabetes are at risk of kidney problems, which could reverse any possible benefits a high-protein diet may bring them. Eating a lot of meat has also been associated with certain common cancers, notably prostate and colon cancers. A 2002 study suggested that such diets during pregnancy may increase the risk for high blood pressure in the child.

Still, significant studies say that such diets improve cholesterol and blood sugar levels. Studies in 2002 and 2003 have indicated that these diets lower blood glucose levels, which can be important in people who are diabetic. The diets also reduce triglyceride levels (unhealthy fat molecules) and increases HDL (" good") cholesterol levels. High triglyceride and low HDL levels are important risk factors for heart disease, and are common in people with type 2 diabetes. Studies are mixed on whether this type of diet reduces overall cholesterol or LDL ("bad") cholesterol levels.

Experts that promote the low carbohydrate approach argue that heart problems from obesity are due to insulin disturbances from sugar imbalances. Therefore, they believe that restricting carbohydrates is the best approach for obesity -- especially for overweight people with diabetes. More research is needed, however, to determine the long-term impact of such diets on health.

High-protein, low-carbohydrate diets include Atkins, Protein Power, Sugar Busters, and Dr. Stillman. The Atkins diet is one of the most popular and has a four-phase program:

Induction. For the first 2 weeks, individuals consume no more than 20 grams of carbohydrates a day. The diet consists of pure protein and fats. There is no fruit, bread, grains, starchy vegetables, or dairy products other than cheese, cream, or butter. This phase is not suitable for children, pregnant women, or anyone with kidney disease.
On-going Weight Loss. After the first phase, individuals continue to lose weight while they increase carbohydrate levels by five grams each day.
Premaintenance. When individuals get close to their weight goal, they add another 10 grams of carbohydrates per day as long as they do not begin to gain weight. Weight loss is very slow at this time, but the individual is now getting used to maintenance.
Maintenance. Lifetime maintenance is usually between 40 and 100 grams of carbohydrates a day, depending on steady weight level.

Anyone who chooses this diet should prefer fish or soy products to meat as protein sources. Fish may reduce leptin, a hormone associated with fat storage and heart diseases, and would be the best protein source. People on this diet should also choose monounsaturated fats (as in olive oil) over saturated fats or trans-fatty acids fat. Patients often need supplements, at least a multivitamin and possibly calcium, chromium, omega-3 fatty acids (found in fish oil), and other supplements.

The South Beach and Zone diets encourage healthy fats. They also allow certain carbohydrates. For example the Zone uses healthy carbohydrates (vegetables and dried beans) and unsaturated fats. The South Beach diet uses carbohydrates that have a lower impact on blood sugar levels. This is called a low-glycemic index. Low-glycemic foods include barley, dried bean and peas, milk, strawberries, and apples. High-glycemic foods include refined grains, white bread, white potatoes, and bananas and other tropical fruits. The glycemic index was developed for use in diabetes -- not for weight loss. Nevertheless, there is some evidence that foods with low glycemic indexes may produce a feeling of fullness and so discourage further eating. As with any high-protein diets, people at risk for kidney stones, or those who have other kidney problems, should avoid these plans.

Replacing fats and sugars with substitutes may help many people who have trouble maintaining weight. In fact, in one 2003 study, people with type 2 diabetes used the artificial sweetener sucralose and a beta-glucan fat substitute (derived from oats) as part of a low-calorie diet. At the end of the 4 weeks, they achieved better weight, glucose control, and HDL levels than those on a standard diabetic diet.

Fat Substitutes. Fat substitutes added to commercial foods or used in baking deliver some of the desirable qualities of fat, but do not add as many calories. It should be stressed that eliminating all fats from a diet can be harmful to general health.

Fat substitutes include the following:

Stanols. Stanols are plant compounds used in margarines (Benecol, Take Control). Benecol is derived from pine bark and Take Control from soybeans. Two servings a day of either brand, as part of a low-fat, diet can lower LDL and total cholesterol by impairing its absorption in the intestinal tract. Some studies have reported that the use of stanols can allow lower doses of statins (cholesterol lowering medications). Stanols do not appear to block absorption of fat-soluble nutrients or vitamins, as olestra does.
Olestra (Olean) passes through the body without leaving behind any calories from fat. Studies suggest that it improves cholesterol levels and helps people lose weight when it is used to replace a third of normal dietary fats. (Note that simply adding snacks containing olestra does not appear to have any effect on cholesterol or weight loss.) Early reports of cramps and diarrhea after eating food containing olestra have not proven to be significant. Of greater concern is the fact that even small amounts of olestra deplete the body of certain vitamins and nutrients that may help protect against serious diseases, including cancer. The FDA requires that the missing vitamins be added back to olestra products, but not other nutrients. The side health effects, if any, are unknown.
Beta-glucan is a soluble fiber found in oats and barley. Products using this substance (e.g., Nu-Trim) may reduce cholesterol and have additional health benefits.

A number of other fat-substitutes are also available. Although studies to date are not showing any significant side effects, these products' effect on weight control is uncertain, since many of the products containing them may be high in sugar.

Artificial Sweeteners. Many artificial or low-calories sweeteners are available. A 2002 study confirmed that people who consumed artificial sweeteners and reduced their sugar intake weighed less over time than those who took in similar types and amounts of drinks and food containing sugar. It should be noted that using these artificial sweeteners should not give dieters a license to increase their fat intake. Studies indicate that consuming some sugar is not a significant contributor to weight gain, as long as the total amount of calories in the diet is under control. There is some public concern about chemicals used to produce many of these sweeteners, and the side effects seen in studies using rats. Natural low-calories sweeteners are available that may be more acceptable to many people.

Saccharin (Sugar Twin, Sweet n' Low, Sucaryl, and Featherweight). Saccharin has been used for years. Some studies found that large amounts of saccharin cause bladder cancer in rats. However, the rats were fed huge amounts that do not apply to human diets. Currently there is no evidence that saccharin causes cancer in humans.
Aspartame (Nutra-Sweet, Equal, NutraTase). Aspartame has come under scrutiny because of rare reports of nervous system disorders, including headaches or dizziness, associated with its use. People with phenylketonuria (PKU), a genetic condition, should not use it. Studies have not reported any serious health dangers, but some people may be sensitive to it.
Sucralose (Splenda). Sucralose has no bitter aftertaste and works well in baking, unlike other artificial sweeteners. It is made from real sugar by replacing part of the sugar with chlorine. Some people are concerned because chlorinated molecules used in major industrial chemicals have been associated with cancer and birth defects. Over 100 studies have been conducted on sucralose over a 20-year period, with no reports of such risks.
Acesulfame-potassium (Sweet One, SwissSweet, Sunette). It has been used in the U.S. since 1988 with no reported side effects.
Neotame (Neotame). Neotame is a synthetic variation of aspartame, but was developed to avoid its side effects. The association with aspartame has raised some concerns. Studies to date have reported no effects that would cause alarm, and it appears to be safe for general consumption.
D-tagatose (Tagatose). This reduced-calorie sweetener is made from lactose, which is the sugar found in dairy products and other foods. It may be especially beneficial for people with type 2 diabetes. It may also have additional benefits that help the intestinal tract.
Alitame (Aclame) is formed from amino acids, the building blocks of proteins. It has the potential to be used in all products that contain sugar, including baked goods.
Stevioside (Stevia). This is a natural sweetener derived from a South American plant. It is available in health food stores. People with diabetes should avoid alcohol-based forms. It has not been carefully tested.

Other sugar substitutes being investigated include glycyrrhizin (derived from licorice) and dihycrochalcone (derived from citrus fruits).

Some studies have reported good success with meal replacement beverages (Slim-Fast, Sweet Success). They contain major nutrients needed for daily requirements. Each serving typically contains between 200 - 250 calories and replaces one meal. (Note: Using them for all meals reduces calories to a severe extent and can be harmful.)

One study reported that most subjects who had undergone a 12-week weight loss program and then used Ultra Slim Fast supplements as directed for maintenance kept off more than half their weight loss after more than 3 years. A quarter of the subjects were still losing weight.

Medical evidence suggests that a diet rich in magnesium could reduce a person's risk of metabolic syndrome, a cluster of problems including obesity, high blood pressure, and high cholesterol. Metabolic syndrome can lead to diabetes and heart disease. A long-term study of thousands of Americans found that the risk for metabolic syndrome decreased in those who consumed the most magnesium from meals. The findings were published in the journal Circulation.

Commercial and Non-Profit Support Programs for Weight Loss. There are many different types of weight-loss program. (This report cannot address all of the many commercial and nonprofit weight-loss programs currently available, nor can it assess their claims.)

Taking off Pounds Sensibly (TOPS), a nonprofit support organization with many local chapters, is one of the least expensive programs, costing $20 a year.

Most of the commercial programs such as Weight Watchers, Jenny Craig, and NutriSystem offer individual or group support, lifestyle changes and packaged meals. These programs tend to be expensive. There are few well-conducted studies on these programs. One 2003 study reported modest weight loss over 2 years with Weight Watchers compared to a self-help program. There were no differences in heart risk factors.

Cognitive Behavioral Approaches. Most support programs use some form of cognitive-behavioral methods to change the daily patterns associated with eating. They are very useful for preventing relapse after initial weight loss. The following is a typical approach:

The patient first records in a diary all activity related to eating patterns, including the times of day, length of meal, emotional states, companions, and, of course, the kind and amounts of food eaten. Most people -- even professional dieticians, according to one study -- tend to underreport their daily calorie intake. However, writing it down is still a good method for increasing a person's awareness of eating patterns. (One patient said that recording circumstances surrounding relapses was a particularly valuable guide for understanding the stresses leading to her own eating behaviors.)
The patient reviews the diary with a therapist or group to set realistic goals and identify patterns that the patient can change. For instance, if food is normally eaten while watching television, then the patient may be advised to eat in another room instead.
Good eating habits are reinforced by rewards. These rewards are other pleasures that substitute the high calorie consumption and sedentary activities.

Behavioral modification has been shown to be helpful particularly for people who have an overly strong response to the taste, smell, and appearance of food. It also may be useful for binge eaters.

Stress-Reduction Techniques. Stress reduction and relaxation techniques may be helpful for some people with obesity, such as those whose weight is related to night-eating syndrome. [See In-Depth Report #31: Stress.]

Changing Sedentary Habits. Making even small changes in physical activity can expend energy. For example, simply getting up to turn the TV on and off instead of using the remote, and standing (instead of sitting) while talking on the phone may help a person lose up to five pounds a year. Other suggestions include cooking one's own food (instead of eating take-out or fast food), walking to as many places as possible, using stairs instead of escalators or elevators, and gardening. Even fidgeting may be helpful in keeping pounds off, and, in one study, chewing gum increased energy expenditure.

No one should rely on such mild activities, however, for serious weight loss. Only high levels of physical activity -- not just using up energy -- help prevent obesity.

Approach to Exercise. Exercise, which replaces fat with muscle, is the critical companion for any weight control program. In a one-year study, women who regularly averaged 3.5 days (176 minutes) of exercise each week lost significantly more weight than women who did not exercise regularly. Women who exercised more than 195 minutes a week lost nearly 7% of their abdominal fat.

People who exercise are more apt to stay on a diet plan. Exercise improves psychological well-being and replaces sedentary habits that usually lead to snacking. Exercise may even act as a mild appetite suppressant. Moreover, exercise improves overall health even with modest weight loss. In support of this, a British study found that overweight fit individuals had half the death rate of unfit trim individuals.

Be aware, however, that the pounds won't melt off magically. Losing significant weight requires both intensive exercise and calorie restriction. In addition, if a person exercises but doesn't diet, any actual pounds lost may be minimal, because denser and heavier muscle mass replaces fat. Nonetheless, regardless of weight loss, a fit body will look more toned and be healthier. In addition, exercise benefits the heart even with modest weight loss.

The following are some suggestions and observations on exercise and weight loss:

The more strenuous the exercise, the better the chances for short-term and long-term success. With intense exercise, the metabolism continues to burn calories before returning to its resting level. This state of elevated metabolism can last for as little as a few minutes after light exercise to as long as several hours after prolonged or heavy exercise.
Of the standard aerobic machines, the treadmill burns the most calories. It may be particularly effective when used in short multiple bouts during the day. In fact, frequent exercise sessions as short as 10 minutes in duration (about four times a day) may be the most successful exercise program for obese people.
Resistance, or strength, training is excellent for replacing fat with muscles. It should be performed two or three times a week.
As people slim down, their initial level of physical activity becomes easier and they burn fewer calories per mile of walking or jogging. The rate of weight loss slows down, sometimes discouragingly so, after an initial dramatic head start using diet and exercise combinations. People should be aware of this phenomenon and keep adding to their daily exercise program.
As people age, they also need to exercise more to keep off the same amount of weight.
Changes in fat and muscle distribution may differ between men and women as they exercise. Men tend to lose abdominal fat (which lowers their risk for heart disease faster than reducing general body fat). Exercise, however, does not appear to have the same effect on weight distribution in women. In one interesting study, women in aerobic and strength training programs lost fat in their arms and trunk, but did not gain muscle tissue in these regions.

Warning Note. Because obesity is one of the risk factors for heart disease and diabetes, anyone who is overweight must discuss their exercise program with a doctor before starting. Sudden demanding exercise, in such cases, can be very dangerous. [See In-Depth Report #29: Exercise.]

Medications

There are several different drugs used for weight loss. Unless specifically instructed by a doctor, people should use non-drug methods for losing weight. Except under rare circumstances, pregnant or nursing women should never take diet medications of any sort, including herbal and over-the-counter remedies.

A 2001 study reported that 7% of American adults use nonprescription weight-loss products. People must be cautious when using any weight-loss medications, including over-the counter diet pills and herbal or so-called natural remedies. Buying unverified products over the Internet can be particularly dangerous.

Green tea. Perhaps the best alternative advice for people who are overweight is to drink tea. Studies have indicated that regular tea drinking is associated with lower weight, particularly in people who drink it for years. Green tea specifically has been associated with increased energy expenditure. One study reported that people who took a green tea extract (Exolise) lost weight and reduced their waist size. Better evidence is needed to confirm the results on this supplement.

Thermogenic Approach to Weight Loss. An approach to weight loss called thermogenic (also hepatothermic) therapy is based on the idea that certain natural compounds have properties that enable the liver to increase energy in the cells and stimulate the metabolism. Theoretically, the result would be fat loss. Among the natural substances used in such products are EPA-rich fish oil, sesamin, hydroxycitrate, pantethine, L-carnitine, pyruvate, aloe vera, aspartate, chromium, coenzyme Q10, green tea polyphenols, aloe vera, DHEA derivatives, cilostazol, diazoxide, and fibrate drugs.

Nearly all the current over-the-counter dietary aids contain some combination of these ingredients. There is no evidence that any of these ingredients can produce weight loss, and some may even have harmful effects.

Chromium is a common ingredient in many diet supplements (e.g., Xenadrine, Dexatrim, Acutrim Natural, Twinlab Diet Fuel). It is claimed to specifically promote fat loss, rather than lean muscle loss. Some evidence suggests that niacin-bound chromium may improve insulin sensitivity. On the negative side, animal studies have suggested that chromium may have damaging effects on genetic materials in cells. This could cause sterility.

Ephedra, Ephedrine, and Ma Huang. The FDA does not allow the sale of drugs that contain ephedrine. In May 2004, the FDA banned the sale of dietary supplements that contain ephedra (also called Ma Huang). Ephedra has been linked to serious side effects, including strokes and heart attacks.

Brazilian Diet Pill. The US Food and Drug Administration (FDA) is warning consumers not to buy a product known as the "Brazilian diet pill." This product is labeled as a dietary supplement, but contains several chemicals found in powerful prescription drugs. The products are also known as Emagrece Sim and Herbathin dietary supplements.

Conjugated Linoleic Acid (CLA). Conjugated linoleic acid is found in many dietary products (e.g., Biosculpt Liquid, Body Success, GNC Optibolic Body Answers Dietary Formula). There is no evidence that it produces weight loss. Furthermore, there is some concern that CLA might increase insulin resistance and a dangerous inflammatory response in people with obesity.

Tiratricol. Over-the-counter products containing tiratricol, a thyroid hormone, have been sold for weight loss. Such products may increase the risk for thyroid disorders, heart attack, and stroke.

Laxative Actions in Natural Substances. Many dietary herbal teas contain laxatives, which can cause gastrointestinal distress, and, if overused, may lead to chronic pain, constipation, and dependency. In rare cases, dehydration and death have occurred. Some laxative substances found in teas include senna, aloe, buckthorn, rhubarb root, cascara, and castor oil.

Guar Gum. Some fiber supplements containing guar gum have also caused obstruction of the gastrointestinal tract.

Chitosan. Chitosan, a dietary fiber from shellfish, prevents a small amount of fat from being absorbed in the intestine. Well-conducted studies, however, have not found it to be effective. Products containing it include Cheat & Lean Fat Blocker, Natrol, Chroma Slim, and Enforma. People who are allergic to shellfish should not take these supplements.

Plantain. Dietary remedies that list the ingredient plantain may contain digitalis, a powerful chemical that affects the heart. NOTE: This substance should not be confused with the harmless banana-like plant also called plantain.

Orlistat (Xenical) can help about one-third of obese patients with modest weight loss, and can assist in long-term maintenance of weight loss. It works by slowing the absorption of fat (by about 30%) in the intestine. Studies indicate that between 50 - 80% of patients can achieve weight loss of 5% or greater, depending on other lifestyle changes. However, many people regain a significant portion of this weight back within 2 years. It does not work for all patients, however. In one survey of patients who took it, 10% gained weight or did not lose any, and 43% lost less than 5%. Nevertheless, orlistat may delay or even prevent the onset or progression of diabetes and improve cholesterol levels, regardless of weight loss.

The drug can cause gastrointestinal problems and may interfere with absorption of the fat-soluble vitamins A, D, and E and other important nutrients. The most unpleasant side effect is oily leakage of feces from the anus. Restricting fats can reduce this effect. People with bowel disease should probably avoid it. In spite of these side effects, most patients are able to tolerate this agent.

In February 2007, the FDA approved an over-the-counter (OTC) version of orlistat. It will be sold under the name alli, and will be available at half the prescription strength of Xenical. Those eager to use the new pill should consider its cost and modest benefits compared with its side effects, most commonly oily diarrhea. This pill, which prevents fat absorption from food, also increases the risk of not absorbing important nutrients from food while using it. The FDA recommends taking a daily multivitamin supplement when using alli.

Sibutramine (Meridia) helps balance the brain chemicals serotonin and norepinephrine. This helps increase metabolism, causes a feeling of fullness, and increases energy levels. It may be particularly useful for binge-eaters. Studies indicate that sibutramine is effective in achieving weight loss, although the weight loss slows considerably after the first 3 months. The drug also appears to improve cholesterol and lipid (fat) levels, and may have other effects that benefit the heart.

Side effects of sibutramine are common. They include dry mouth, constipation, and insomnia. In one study, almost half the patients dropped out as a result of these side effects. There have been reports of increases in heart rate and blood pressure while taking this medication, although a 2001 study indicates that blood pressure stabilizes over time.

At this time, people who have a history of high blood pressure, stroke, heart disease, or arrhythmias should not take this drug. People taking decongestants, bronchodilators (such as for asthma), monoamine oxidase inhibitors, or serotonin reuptake inhibitors should also avoid sibutramine.

Phentermine and Other Sympathomimetics. Sympathomimetics are drugs that act like the stress hormone (and chemical messenger) norepinephrine. These medications act as stimulants in the brain. Some are approved for treating obesity, but only for short-term use. They include:

Phentermine (Ionamin, Adipex-P, Fastin)
Benzphetamine (Didrex)
Phendimetrazine (Adipost, Bontril, Melfiat, Plegine, Prelu-2, Statobex)

Phentermine is the most commonly prescribed appetite suppressant, and is less expensive than orlistat or sibutramine. Its effects are not long lasting, however. It can also raise blood pressure. In addition, phentermine is associated with depression, which is already a problem in many cases of obesity. A combination (Phen-Pro) containing phentermine and the antidepressant fluoxetine (Prozac) is being investigated to help reduce this problem. Note: Neither phentermine nor such combinations are associated with the heart problems linked to the previous phentermine combination known as Fen-Phen (phentermine and fenfluramine).

Amphetamines. The amphetamines dextroamphetamine (Dexedrine), methamphetamine (Desoxyn), and phenmetrazine (Pleudin) are powerful stimulants. They were used most often in the past but are no longer prescribed for weight loss. These drugs improve mood and produce some modest weight loss over the short term, but carry serious risks of addiction, agitation, and insomnia.

Rimonabant. Rimonabant (Accompli) belongs to a new class of drugs called selective CB1 blockers. The drug is designed to block receptors in the brain associated with the regulation of eating. Rimonabant also targets receptors in fat tissue. The Rimonabant in Obesity-Lipids (RIO-Lipids) study looked at how rimonabant affected metabolic risk factors in high-risk overweight or obese patients with blood fat disorders. The study involved more than 1,000 participants. The findings, published in the November 2005 New England Journal of Medicine, said that people who took the drug significantly reduced their body weight and size of their waist.

Earlier studies involving the drug reported that obese patients treated with 20 mg of rimonabant lost significantly more weight and inches from their waist than patients who received placebo. The drug also appeared to have beneficial effects on raising HDL ("good") cholesterol levels.

Note: Fake rimonabant has been found for sale on several web sites. Patients should be aware that this drug is still experimental, and rimonabant is not available for sale. Buying and taking counterfeit drugs can have serious health consequences. In addition, an FDA advisory panel in April 2007 rejected the drug, citing fears it may cause psychiatric problems and seizures in some patients.

Axokine. Axokine is a type of drug called a ciliary neurotrophic factor. It signals the brain to suppress one's appetite. It is proving to be effective in achieving weight loss, and also improves cholesterol, lipid, and glucose levels regardless of food intake. It could be particularly helpful for people with type 2 diabetes. Early study results found that severely obese patient who took the drug lost more weight than those who took a dummy pill (placebo). Nearly half (46%) of patients who took the drug lost at least 10 pounds, compared to 5% of those who received the placebo. Study participants tolerated the drug well. There were no reports of serious side effects.

Zonisamide. Zonisamide (Zonegran) is an anti-seizure medication that is also being investigated for weight loss. In one study, patients who took it lost more weight than those on placebo. Zonisamide increases the risk for kidney stones, which can be reduced with increased fluid intake and citrate. It has also been associated with reduced sweating and a sudden rise in body temperature, especially in hot weather. Other side effects include dizziness, forgetfulness, headache, and nausea.

Topiramate. Topiramate (Topamax) is another anti-seizure medication being investigated for weight reduction. Three clinical trials have reported that patients given topiramate lost more weight than those receiving placebo. Weight loss was sustained for up to 1 year. The drug is also being studied for binge-eating disorders associated with obesity.

Other Treatments

Surgical procedures for obesity may be appropriate for some dangerously obese people, and may reduce heart problems and many of the risks associated with obesity. These risks include high blood pressure, sleep apnea, and diabetes. In fact, some evidence suggests that surgery may provide much greater control of weight and diabetes than nonsurgical weight-loss methods. Studies are reporting significant reductions in diabetes, and the need for diabetic medications, after surgery. Other medical conditions that often improve after surgery include heartburn, arthritis, and other joint and circulation problems.

Bariatric surgeries produce weight loss through one of two approaches:

Restrictive Banding Procedures. These procedures restrict the amount of food by closing off parts of the stomach with bands.
Malabsorptive Bypass Procedures. This approach restricts the amount of food and also reduces absorption by using a bypass of parts of the intestine.

The malabsorptive procedures are more successful in achieving weight loss than the banding approach, but they carry a greater risk for nutritional deficiencies.

Most people who have bariatric surgery lose about two-thirds of excess weight within 2 years. In addition, diseases associated with obesity (such as diabetes, high blood pressure, sleep apnea, joint pain, and incontinence) often improve.

Researchers at the Mayo Clinic looked at records from patients who had the surgery between 1990 and 2003. They found that those who had bariatric surgery reduced their risk of cardiovascular events such as a heart attack much more than those who lost weight without surgery. The findings were published in the September 2005 Mayo Clinic Proceedings.

Other studies have shown that even though most patients maintain significant weight loss, the majority regain about to 10% of their weight. Patients must still develop a healthy life style and be calorie conscious after the operation. Follow-up must be life-long.

Any surgical candidate must have failed consistently in losing weight through less invasive methods. Experts recommend bariatric surgery only for the following:

Those whose BMI is above 40 (about 100 pounds overweight)
Those with BMIs of over 35 who have type 2 diabetes or serious obesity-related medical problems
Those with severe obesity that interfered with employment, normal physical activity (e.g., walking), and important relationship

About a third of people who undergo these procedures achieve normal weight, and 80% experience some weigh loss. They are less successful than the bypass procedures, but carry a lower risk of nutritional deficiencies.

Vertical Banded Gastroplasty. Vertical banded gastroplasty (VBG) was the most common restrictive procedure. It involves creating a hole through both stomach walls and sealing the edges with a staple. This narrows the stomach, similar to a funnel, and allows only small amounts of food to pass through.

Laparoscopic Gastric Banding. Laparoscopic gastric banding (the Lap-Band) usually does not require a major incision and avoids some of the major complications of gastric bypass:

It employs an adjustable silicone band that is placed around the upper part of the stomach.
A small balloon-like reservoir attached to the band under the abdominal skin contains saline, which can be added or removed to tighten or loosen the band.
The procedure restricts the amount of food a person can eat and gives the feeling of fullness.

The band is removable, if necessary. Studies to date indicate that the intestinal tract returns to normal afterward. Studies, including those done in the elderly, have reported significant weight loss and improved quality of life with the procedure.

Malabsorptive procedures produce greater weight loss than restrictive procedures. Patients generally achieve about two-thirds of their weight loss within 2 years. Furthermore, in a 2003 study, after standard bypass surgery, 83% of patients with type 2 diabetes experienced normal blood glucose levels and the rest had significant reductions.

Roux-en-Y Gastric Bypass Procedure. This is the most common and successful malabsorptive surgery in the United States. It involves creating a small stomach pouch that serves as a reservoir and restricts food intake. The pouch eventually holds up to 3 ounces of food and has a small outlet that delays emptying and causes a feeling of fullness. Then the surgeon creates a Y-shaped section in the small intestine that attaches to the pouch. This section allows food to bypass the lower stomach and upper part of the intestine. One 2003 study reported that this procedure was associated with significant weight loss, and 80% of patients with type 2 diabetes were able to reduce their medications. A more recent study, published in the March 14, 2006, issue of Archives of Surgery, found that gastric bypass surgery also helps lower the blood pressure of very obese patients.

The procedure produces greater and more sustained weight loss than banding procedures, but it is also more complicated, and carries a higher risk of nutritional deficiencies. Laparoscopy techniques, which are less invasive, are now preferred over open surgery. They achieve equally good results with fewer complications.

Biliopancreatic Diversion. This procedure is more complicated and removes portions of the stomach. The pouch that is created attaches directly to the lower part of the small intestine. It poses a higher risk for nutritional deficiencies than other procedures and is not used as often.

Click the icon to see an image of gastric bypass surgery.

General Side Effects and Complications. Side effects and complications of bariatric procedures are common, and up to 25% of patients require corrective or repeat procedures. After any of these procedures people must chew all their food carefully, and they cannot eat large amounts of food at one time. If patients do not follow these guidelines, they will experience nausea, abdominal distress, or both.

Complications from any bariatric procedure includes the following:

Vomiting: This is the most common complication, and it is most common with banding procedures.
Nutritional deficiencies: There is a strong risk of nutritional deficiencies, particularly with malabsorptive operations. This complication can lead to anemia and increase the risk of bone loss and osteoporosis. Taking enough mineral and vitamin supplements is important after bariatric surgery.
Deep-vein thrombosis: There is a significant risk for deep-vein thrombosis (blood clots in the veins).
Abdominal hernia: This is another common complication. Newer, laparoscopic techniques do not carry this risk, but not all individuals are candidates for this less-invasive approach.
Rapid weight loss after surgery: This complication puts people at high risk for gallstones.
Women who wish to be pregnant should wait until their weight has stabilized. Rapid weight loss and nutritional deficiencies can harm the fetus.

People at highest risk for complications are those with heart or lung problems, severe obesity, and a history of abdominal surgeries. The mortality rate from bariatric surgeries is 0.2%, which is lower than the morality rates from severe obesity itself. Other surgical variations and less invasive techniques using laparoscopy have been developed.

Specific Complications of Restrictive Banding Procedures. Nausea, vomiting, or both occurs in half the patients, and severe heartburn occurs in a third. Device-related complications include band slippage, pouch dilation (widening), or both in nearly a quarter of patients, and obstruction in 12% of patients. Very serious complications are rare, but include blood clots, bleeding, infection, pneumonia, and perforation (tearing) of the stomach.

Specific Complications of Malabsorptive Bypass Procedures. Vomiting often occurs. Nutritional deficiencies occur more often in these procedures. The so-called dumping syndrome is a common unpleasant side effect, which occurs when food waste moves too quickly through the intestine. Symptoms include nausea, weakness, sweating, and faintness (particularly after eating sweets).

Spot Exercising. Anyone seeking to lose weight must expect that the results may not be as cosmetically satisfying as one would wish. Spot exercising (training particular areas of the body) is ineffective in reducing fat in specific locations because exercise draws on fat stores throughout the body. Gimmicky devices such as bust developers, vacuum pants, and exercise belts do absolutely nothing to reduce fat or add bulk in specific locations. Electrical pads wrapped around the waist, arms, or thighs were reported to cause burns and fires.

Cellulite-Removal Creams. Many women try to reduce fat in their thighs (cellulite) with creams that contain aminophylline (Skinny Dip, Thermojetics Body Toning Cream, Smooth Contours). Studies provide no evidence that these creams are effective. Their apparent effect on fat may simply be from narrowing blood vessels and forcing water from the skin, which could be dangerous for people with blood flow problems.

Endermologie. Endermologie uses motorized rollers and regulated suction to smooth out cellulite. In one study, about 28.6% of patients reported improved appearance after using it.

Liposuction. Liposuction eliminates fat in specific areas, such as the abdomen, thighs, buttocks, or knees. Special instruments are inserted through the skin into the pockets and suction is used to move the fat, break it up, and remove it. Small tubes may be used to drain blood and fluid during the first few days. The pain after the operation can be severe and often the skin does not contract, resulting in a flabby look. Complications can include burns from the vibrators, bruising, blood clots, and bleeding. Weight gain generally tends to develop in other locations after the operation. Some doctors are using this procedure in overweight people with diabetes to remove abdominal fat. Although there is no proof that it has an effect on diabetes, some experts believe the procedure deserves attention.

Liposuction is not recommended for major weight loss.

Resources

www.healthierus.gov/dietaryguidelines -- Dietary Guidelines for Americans 2005
www.naaso.org -- North American Association for the Study of Obesity
www.eatright.org -- American Dietetic Association
www.nutrition.gov. -- Nutrition.gov
www.asbs.org -- American Society for Bariatric Surgery
www.cnpp.usda.gov -- Center for Nutrition Policy and Promotion
http://fnic.nal.usda.gov -- Food and Nutrition Information Center
www.americanheart.org -- American Heart Association
www.nationaleatingdisorders.org -- National Eating Disorders Organization
www.aabt.org -- Association for Advancement of Behavior Therapy
www.fda.gov -- Food and Drug Administration
http://win.niddk.nih.gov -- Weight-Control Information Network

References

US Food and Drug Administration FDA Approves Orlistat for Over-the-Counter Use. Rockville, MD: National Press Office; February 7, 2007.

Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999-2004. Journal of the American Medical Association. 2006; 295:1549-1555.

National Center for Health Statistics. Chartbook on Trends in the Health of Americans. Health, United States, 2005. Hyattsville, MD: Public Health Service. 2005

National Institute of Diabetes and Digestive and Kidney Diseases - Weight-control Information Network. Statistics Related to Overweight and Obesity. Available online.

National Center for Health Statistics. Prevalence of Overweight Among Children and Adolescents: United States, 2003-2004.

Morino M, Toppino M, Bonnet G, Rosa R, et al. Laparoscopic vertical banded gastroplasty for morbid obesity. Assessment of efficacy. Surg Endosc. 2002 Nov;16(11):1566-72.

Brethauer SA, Schauer PR, Chand B. Risks and benefits of bariatric surgery: Current evidence. Cleveland Clinic Journal Of Medicine. 2006 Nov; 73(11): 993-1007.

Rosenthal RJ, Szomstein S, Kennedy CI, et al. Laparoscopic surgery for morbid obesity: 1,001 consecutive bariatric operations performed at The Bariatric Institute, Cleveland Clinic Florida. Obes Surg. 2006 Feb;16(2):119-24.

He K, Liu K, Daviglus ML, et al. Magnesium Intake and Incidence of Metabolic Syndrome Among Young Adults. Circulation. 2006: Published online before print. March 27, 2006.

Chen TY, Smith W, Rosenstock JL, Lessnau KD. A life-threatening complication of Atkins diet. Lancet. 2006 Mar 18;367(9514):958.

Lopez-Jimenez F, Bhatia S, Collazo-Clavell ML, Sarr MG, Somers VK. Safety and efficacy of bariatric surgery in patients with coronary artery disease. Mayo Clin Proc. 2005 Sep;80(9):1157-62.

Sidhaye A, Cheskin LJ. Pharmacologic treatment of obesity. Adv Psychosom Med. 2006;27:42-52.

Fernstrom JD, Courcoulas AP, Houck PR, Fernstrom MH. Long-term changes in blood pressure in extremely obese patients who have undergone bariatric surgery. Arch Surg. 2006 Mar;141(3):276-83.

Despres JP, Golay A, Sjostrom L; Rimonabant in Obesity-Lipids Study Group. Effects of rimonabant on metabolic risk factors in overweight patients with dyslipidemia. N Engl J Med. 2005 Nov 17;353(20):2121-34.

Lanningham-Foster L, Nysse LJ, Levine JA. Labor saved, calories lost: the energetic impact of domestic labor-saving devices. Obes Res. 2003 Oct;11(10):1178-81.

Review Date:
6/14/2007
Reviewed By:
A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy. Previously reviewed by Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital (4/30/2007).

A.D.A.M. Copyright

adam.com

Osteoarthritis

FitSugar — Wed, 08 Oct 2008 17:34:56 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Conditions with Similar Sym...
Risk Factors
Diagnosis
Prognosis
Lifestyle Changes
Medications
Alternative and Complementa...
Surgery
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Pain Medications

Nonsteroidal anti-inflammatory drugs (NSAIDs) and COX-2 inhibitors work equally well for pain management, but both types of drugs increase the risk for heart attacks, according to an important report from the U.S. Agency for Healthcare Quality and Research.
The prescription NSAID diclofenac (Voltaren, Cataflam) may present a higher risk for heart attack than other NSAIDs, suggests a 2006 Journal of the American Medical Association study.
Standard osteoarthritis medications provide moderate pain relief for only 2 - 3 weeks, suggests a 2007 review in the European Journal of Pain.

Acupuncture

Acupuncture may be helpful for people with knee and hip osteoarthritis, according to several 2006 studies:

An Annals of Internal Medicine study of 1,007 people with chronic osteoarthritis knee pain indicated that patients who received acupuncture plus standard care had greater improvement than those who received only physical therapy and anti-inflammatory drugs.
An Arthritis and Rheumatism study of 3,663 patients with chronic osteoarthritis knee or hip pain suggested that acupuncture plus routine care can provide significant improvements in pain relief and quality of life. In both studies, the benefits of acupuncture were sustained for up to 6 months after treatment completion.

Exercise and Knee Osteoarthritis

Weight-bearing exercise (walking, jogging) neither prevents nor increases the risk of knee osteoarthritis in healthy middle-aged and elderly people, suggests a 2007 study in Arthritis and Rheumatism.

Risk of Hip Osteoarthritis

About 1 in 4 Americans can expect to develop osteoarthritis of the hip at some point in life, according to research presented at the 2006 American College of Rheumatology annual meeting. Body weight is a factor. People who are normal weight have a 20% risk, compared to those who are overweight (25%) or obese (39%).

Introduction

Osteoarthritis, also known as degenerative joint disease, is the most common form of arthritis. Scientists now believe osteoarthritis results from a combination of genetic abnormalities and joint injuries. In this disorder, an affected joint experiences a progressive loss of cartilage, the slippery material that cushions the ends of bones.

Osteoarthritis is a chronic disease of the joint cartilage and bone, often thought to result from "wear and tear" on a joint, although there are other causes such as congenital defects, trauma, and metabolic disorders. Joints appear larger, are stiff and painful, and usually feel worse with increased use throughout the day.

As a result, the bone beneath the cartilage undergoes changes that lead to bony overgrowth. The tissue that lines the joint can become inflamed, the ligaments can loosen, and the associated muscles can weaken. The patient experiences pain when using the joint. In addition to humans, nearly all vertebrates suffer from osteoarthritis, including porpoises and whales, as did long-extinct terrestrial travelers such as dinosaurs.

Click the icon to see an animation about osteoarthritis.

Joints are designed to provide flexibility, support, stability, and protection. These functions, essential for normal and painless movement, are primarily supplied by specific parts of the joint: the synovium and cartilage.

Synovium. The synovium is a membrane that surrounds the entire joint. It is filled with synovial fluid, a lubricating liquid that supplies nutrients and oxygen to cartilage.

Cartilage. The cartilage is a slippery tissue that coats the ends of the bones. Cartilage is one of the few tissues in the body that does not have its own blood supply. It has a number of essential components:

Click the icon to see an image of the synovial membrane and cartilage in the knee joint.

Chondrocytes. Chondrocytes, the basic cartilage cells, are critical for balance and function.
Water. Cartilage contains a high percentage of water, although it decreases with age. About 85% of cartilage is water in young people, and about 70% is water in older individuals.
Proteoglycans. These are large molecules that help make up cartilage. Their important value is their capacity to bond to water, which ensures the high-fluid content in cartilage.
Collagen. This is the critical protein in cartilage. It forms a mesh to give support and flexibility to the joint. Collagen is the main protein found in all the connective tissues of the body, including the muscles, ligaments, and tendons.

The combination of the collagen meshwork and the high water content, tightly bound by proteoglycans, creates a resilient and slippery pad in the joint, which resists the compression between bones during muscle movement. The synovial fluid lubricates and provides oxygen and nutrients to the bloodless cartilage.

Deterioration of Cartilage. Osteoarthritis develops when cartilage in a joint deteriorates. The process is usually slow.

In the early stages of the disease the surface of the cartilage, or even the synovium in some people, becomes inflamed and swollen. There is a loss of proteoglycan molecules and other tissue components that cause water loss. Fissures and pits appear in the cartilage.
As the disease progresses and more tissue is lost, the cartilage loses elasticity and fluid. It becomes increasingly prone to damage due to repetitive use and injury.
Eventually large amounts of cartilage are destroyed, leaving the ends of the bone within the joint unprotected.

To compound the process, bone around arthritic joints is not structurally normal. As the body tries to repair damage to the cartilage, problems can develop:

Clusters of damaged cells or fluid-filled cysts may form around the bony areas or near the fissures.
Fluid pockets may also form within the bone marrow itself, causing swelling. The marrow, which runs up through the center of bone, is rich in nerve fibers, and such injuries may be an important source of pain in many patients with osteoarthritis.
Bone cells may respond to damage by multiplying, growing, and forming dense, misshapen plates around exposed areas.
At the margins of the joint, the bone may produce outcroppings, on which new cartilage cells (chondrocytes) proliferate and grow abnormally.

Unlike some other types of arthritis, such as rheumatoid arthritis, osteoarthritis does not spread through the entire body. (In other words, it is not systemic.) Rather, it affects one or several joints. Osteoarthritis affects joints differently depending on their location in the body.

Osteoarthritis is commonly found in joints of the fingers, feet, knees, hips, and spine.
It sometimes occurs in the wrist, elbows, shoulders, and jaw, but is not common in these locations.

Causes

The biologic factors leading to the deterioration of cartilage in osteoarthritis are not entirely understood. Many experts believe that osteoarthritis results from a genetic susceptibility that causes some biologic response to injuries to the joint, which in turn leads to progressive deterioration of cartilage. In addition, the ability to make repairs becomes progressively limited as cartilage cells age.

Although osteoarthritis generally accompanies aging, osteoarthritic cartilage is chemically different from normal aged cartilage. As chondrocytes (the cells that make up cartilage) age, they lose their ability to make repairs and produce more cartilage. This process may play an important role in the development and progression of osteoarthritis.

Researchers report a high correlation of osteoarthritis between parents and children or between siblings. Genetic factors are thought to be involved in about half of osteoarthritis cases in the hands and hips and a somewhat lower percentage of cases in the knee. A number of genes are under investigation that might contribute to an inherited risk.

For example, mutations in the ank gene may be important in some cases. The ank gene regulates pyrophosphate, a chemical that inhibits the formation of mineral deposits, and may protect the cartilage in joints. Mutations in the ank gene then may result in lower pyrophosphate levels in the joint, leading to accumulation of mineral deposits and arthritis. (About 60% of people with osteoarthritis have mineral deposits in their cartilage.)

Another gene, called the osteoprotegerin gene, is important in regulating bone and cartilage formation. Mutations in this gene may play a role in osteoarthritis.

The inflammatory response is an overreaction of the immune system to an injury or other assault in the body, such as an infection. This response causes specific immune factors, called cytokines, to gather in injured areas and cause inflammation and damage to body tissue and cells. The inflammatory response plays an important role in rheumatoid arthritis and other muscle and joint problems associated with autoimmune diseases. It has generally been believed that inflammation plays at most a minor role in osteoarthritis and is more likely to be a result -- not a cause -- of the disease.

However, recent studies suggest that inflammation may play an important role in the progression of osteoarthritis and its chronic nature. For example, a 2003 study found evidence of severe inflammation in the lining of the joints in 30% of patients with osteoarthritis. Still, the effects of the inflammatory response in osteoarthritis are likely to be different from those in rheumatoid arthritis and less severe.

Some theories on how this response may contribute to osteoarthritis involve overproduction of enzymes called matrix metalloproteinases or MMPs (also called collagenases). In large amounts they break down collagen, the building blocks of cartilage. Some studies suggest that immune factors called vascular endothelial growth factor (VEGF) are overproduced during the inflammatory response and in turn increase production of MMPs.

Another theory suggests that the inflammatory response is triggered by the changes and injuries in the bone that occur during osteoarthritis. According to this theory, immune factors released in this process diffuse into the cartilage, where they suppress cartilage cell growth and activate MMPs.

Joint injuries are the starting point in the disease process. Osteoarthritis sometimes develops years after a single traumatic injury to or near a joint. One large study found that by age 65, osteoarthritis developed in almost 14% of those who had joint injuries as young adults, compared to just 6% in those without earlier injuries. Patients with knee injuries were five times more likely to have osteoarthritis in the injured knee than those without injuries, and patients with hip injuries were more than three times more likely to develop arthritis in the injured hip. Proper treatment of injuries, such as surgical repair of ligament tears in the knee with a strong rehabilitation approach, may help to prevent the development of osteoarthritis.

Other causes of osteoarthritis include:

Bleeding disorders such as hemophilia that cause bleeding to occur in the joint
Disorders such as avascular necrosis that block the blood supply near the joint
Complications of persistent, inflammatory arthritic conditions, particularly chronic gout, pseudogout, or rheumatoid arthritis
Conditions that cause iron build-up in the joints such as hemochromatosis

Symptoms

The pain of osteoarthritis typically begins gradually and progresses slowly over many years. People under age 40 may have the condition with no symptoms at all. Osteoarthritis is commonly identified by the following symptoms:

The most common symptom of osteoarthritis in any joint is pain that worsens during activity and gets better during rest. As the disease advances, the pain may occur even when the joint is at rest.
Pain is generally described as aching, stiffness, and loss of mobility.
The pain may behave like a roller coaster, with bad spells followed by periods of relative relief.
Pain seems to increase in humid weather.
Some people experience muscle spasm and contractions in the tendons.
Osteoarthritis in the knee may cause a crackling-like noise (called crepitus) when moved.

Hand. Osteoarthritis of the hand occurs most often in older women and may be inherited within families. The following joints are most frequently affected:

Distal interphalangeal (DIP) joint. The first joint below the fingertips is the most common location of osteoarthritis of the hand. These joints can develop bony growths known as Heberden's nodes.
Carpometacarpal (CMC) joint. The joint at the base of the thumb, where the thumb joint connects with the wrist, is the second most common location.
Proximal interphalangeal (PIP) joint. The middle joints of the fingers can also develop osteoarthritis. These joints may develop small, solid lumps (nodules) known as Bouchard's nodes.

Click the icon to see an image of osteoarthritis.

Recent studies suggest that osteoarthritis of the hand may predict the later development of osteoarthritis in the hip or knee. A 2005 study found that patients with hand osteoarthritis were three times more likely to develop hip arthritis. Osteoarthritis of the hand also slightly increased the risk for knee osteoarthritis.

Knee. Osteoarthritis is particularly debilitating in the weight-bearing joints of the knees. The joint is usually stable until the disease reaches an advanced stage when the knee becomes enlarged and swollen. Although painful, the arthritic knee usually retains reasonable flexibility.

Osteoarthritis can cause loss of cartilage in the knee. The meniscus, the cartilage pad between the joint formed by the thighbone and the shinbone, plays an important role in protecting the joint. It acts as a shock absorber. In knee surgery called meniscectomy, the doctor removes the damaged cartilage. However, a 2006 study suggested that preserving the meniscus, even if it is damaged, is better than removing it. Researchers showed that even a small amount of meniscus helps protect the joint and prevent osteoarthritis from worsening. Experts recommend that patients try lifestyle changes (exercise and weight loss), braces, and medication before undergoing knee surgery.

Click the icon to see an image of the knee joint.

Hips. About 1 in 4 people will develop hip arthritis over the course of their lifetime. Being obese increases the risk. Osteoarthritis frequently strikes the weight-bearing joints in one or both hips. Pain develops slowly, usually in the groin and on the outside of the hips, or sometimes in the buttocks. The pain also may radiate to the knee, confusing the diagnosis. Those with osteoarthritis of the hip often have a restricted range of motion (particularly when trying to rotate the hip) and walk with a limp, because they slightly turn the affected leg to avoid pain.

Click the icon to see an image of the hip joint.

Spine. Osteoarthritis may affect the cartilage in the disks that form cushions between the bones of the spine, the moving joints of the spine itself, or both. Osteoarthritis in any of these locations can cause pain, muscle spasms, and diminished mobility. In some cases, the nerves may become pinched, which also produces pain. Advanced disease may result in numbness and muscle weakness. Osteoarthritis of the spine is most troublesome when it occurs in the lower back or in the neck, where it can cause difficulty in swallowing.

Click the icon to see an image of the spine.

Shoulder. Osteoarthritis is less common in the shoulder area than in other joints, but it may develop in the shoulder joint (the glenohumeral joint). In such cases, it is most often associated with a previous injury, and patients gradually develop pain and stiffness in the back of the shoulder. Osteoarthritis also can develop in the acromioclavicular (AC) joint, which is between the shoulder blade and the collarbone. However, it rarely causes symptoms in this location.

Conditions with Similar Symptoms

Numerous conditions have symptoms of joint aches and pains. Something as benign as sleeping on a bad mattress to the serious afflictions associated with cancer can mirror symptoms of osteoarthritis. Other problems that can cause aches and pains in the joints include physical injuries, infections, tendinitis, and poor circulation. A number of rare genetic diseases attack the joints.

Osteoarthritis can generally be distinguished from other joint diseases by considering several factors together:

Osteoarthritis usually occurs in older people and is located in only one or a few joints
The joints are less inflamed than in other arthritic conditions
Progression of pain is usually gradual.

A few of the most common disorders that can be confused with, or may even accompany, osteoarthritis are discussed below.

Osteoarthritis may be confused with rheumatoid arthritis, particularly when osteoarthritis affects multiple joints in the body. Rheumatoid arthritis begins in the synovial membrane rather than the cartilage. It normally occurs earlier in life than osteoarthritis, often striking people in their 30s and 40s. Rheumatoid arthritis affects many joints, and often occurs symmetrically on both sides of the body. People generally have morning stiffness that lasts for at least an hour. (Stiffness from osteoarthritis usually clears up within half an hour.)

X-rays show changes in the bones that differ from those occurring in osteoarthritis. In rheumatoid arthritis, blood tests often show a specific antibody, known as rheumatoid factor, which is not present with osteoarthritis. In another blood test, levels of a factor called erythrocyte sedimentation rate (ESR) are often elevated in rheumatoid arthritis, but they are generally normal in osteoarthritis. Rheumatoid arthritis also does not usually show up in the fingertips where osteoarthritis is common.

Rheumatoid arthritis is a body-wide (systemic) autoimmune disease that initially attacks the synovium, a connective tissue membrane that lines the cavity between joints and secretes a lubricating fluid.

Click the icon to see an image of osteoarthritis vs. rheumatoid arthritis.

Chondrocalcinosis is a disease in which certain calcium crystals known as CPPD (calcium pyrophosphate dihydrate) are deposited in the joints. It affects about 25% of the population and can accompany and even worsen osteoarthritis. The problem has been called pseudogout or pseudo-osteoarthritis, in the latter case particularly when it affects the knees. A doctor can usually differentiate between the two disorders, however, because chondrocalcinosis usually damages other joints (such as wrists, elbows, and shoulders) that are not usually affected by osteoarthritis. The condition may explain why some patients with osteoarthritis receive benefit from colchicine, a drug used for gout and other crystal-induced joint diseases.

Charcot's joint occurs when an underlying disease, usually diabetes, causes nerve damage in the joint, which leads to swelling, bleeding, increased temperature, and changes in bone. There may be a loss of sensation that leads to an increased risk for injury from overuse.

Risk Factors

Osteoarthritis is the most common type of arthritis. In the U.S., about 12.1% of Americans (21 million people) age 25 and older have osteoarthritis. The prevalence in osteoarthritis increases as people age. Experts estimate that by 2030, 20% of Americans (72 million people) age 65 years and older will be at risk for developing osteoarthritis.

Before age 45, osteoarthritis occurs more frequently in males (although it is not common in younger adults). After age 55, it develops more often in females. In a 2000 study, 33% of women had osteoarthritis compared to 25% of men. Some research suggests that women may also experience greater muscle and joint pain, in general, than men. And, women also tend to be undertreated for pain compared to men. The causes of such differences in pain sensitivity and treatment are largely unknown and most likely are due to a complicated mix of biologic, psychologic, and social factors.

The incidence is highest in lower educational levels. In a 2000 study, 41% of adults with less than a high school education had arthritis compared to 21% of college graduates.

Although the average rate of osteoarthritis among older adults in the U.S. is 60%, it can vary widely in certain geographical regions. In the U.S., the rates in older adults are lowest (34%) in Hawaii and highest (70%) in Alabama. In general, the highest prevalence of arthritis in America occurs in the central and northwestern states.

The rate of osteoarthritis varies by ethnic group. In the U.S., Caucasians and African-Americans have higher rates of arthritis than Hispanics or other ethnic groups. Osteoarthritis also tends to favor specific joints over others in certain ethnic groups. The following are some examples:

Older African-American men are about 33% more likely than Caucasian men to have hip osteoarthritis. In one study, although men in both groups had equal risks for arthritic knees, African-American men were more likely to have arthritis in both knees and to have more severe cases. Although comparable disparities in knee arthritis were observed between African-American and Caucasian women, they might be explained by greater average weight among African-American women. The study could not account for the differences among men, however.
Asians appear to have a higher incidence of osteoarthritis in the knee, an equal risk for osteoarthritis in the spine, and a lower risk for osteoarthritis in the hips than Caucasians.

Genes that determine the angles, amount of force, and other structural factors in the hip joints, or genes that regulate the chemistry in the joints, may account for ethnic differences.

Some researchers suggest that a number of people have anatomical abnormalities, such as mismatched surfaces on the joints, which could be damaged over time by abnormal stress. Legs of unequal length or skewed feet can cause jerky movement and may cause osteoarthritis. One study reported that those whose knees bent inward ("knock-kneed") or outward ("bow-legged"), for example, were more likely to have progressive osteoarthritis of the knee.

Obesity, defined as being 20% over one's healthy weight, places people (particularly women) at increased risk for osteoarthritis. It also worsens osteoarthritis once deterioration begins. This higher risk is due to increased weight on the joints. However, being obese also increases the risk for osteoarthritis in the fingers as well as the knees and hips, suggesting that being overweight may contribute to osteoarthritis in other ways. Some research indicates that obesity may produce an inflammatory response, which is now a major suspect in age-related diseases -- not only osteoarthritis but also heart disease. [See In-Depth Report #53: Weight control and diet.]

Because injuries can trigger the disease process, people whose work or leisure activities place them at risk for muscle and joint injuries may face a higher risk for osteoarthritis later on.

Workers at Higher Risk. Certain occupations that require repeated stressful motions (such as squatting or kneeling with heavy lifting) can contribute to deterioration of cartilage. One study suggested that workers whose jobs require kneeling or squatting for more than an hour a day are at high risk for knee osteoarthritis. (In the study, jobs that involved heaving lifting, climbing stairs, or walking also posed some, but not as high, a risk. Being heavier compounded the chances for osteoarthritis.)

Exercise. There has been some question about the role of strenuous exercise in osteoarthritis. Sports that definitely pose a higher risk for osteoarthritis are those that require repetitive or direct joint impact (such as football), twisting, or both (baseball pitching, soccer).

Marathon runners, however, have a relatively low rate of osteoarthritis. Some scientists speculate that running enhances cartilage health because the rhythmical compression of cartilage expels wastes and promotes absorption of nutrients.

In any case, regular and moderate exercise is important for everyone and does not increase the risk for osteoarthritis. In fact, a 2006 study of middle-aged and elderly people found that recreational weight-bearing exercise (walking, jogging) neither protects against nor increases the risk for osteoarthritis. Furthermore, many factors associated with a sedentary life (muscle weakness, obesity) are associated with a higher risk for osteoarthritis.

Diagnosis

Osteoarthritis is often visible in x-rays. Cartilage loss is indicated by certain images:

If the normal space between the bones in a joint is narrowed.
If there is an abnormal increase in bone density.
If bony projections, cysts, or erosions are evident.
X-rays can also reveal any cysts that might develop in osteoarthritic joints. If other conditions are suspected or if the diagnosis is uncertain, additional tests are necessary.
An MRI may show evidence of osteoarthritis that x-rays miss.

X-rays are a form of electromagnetic radiation (like light); they are of higher energy, however, and can penetrate the body to form an image on film. Structures that are dense (such as bone) will appear white, air will be black, and other structures will be shades of gray depending on density. X-rays can provide information about obstructions, tumors, and other diseases, especially when coupled with the use of barium and air contrast within the bowel.

Blood test results may help diagnose or rule out osteoarthritis. Some examples include:

Elevated levels of rheumatoid factor (specific antibodies in the synovium) and so-called erythrocyte sedimentation rates (ESR or sed rate) indicate rheumatoid arthritis.
Hyaluronic acid (HA), a joint lubricant, is being tested as a potential biomarker for osteoarthritis. High levels of HA may indicate increased risk for osteoarthritis.
Elevated levels of a factor called C-reactive protein, which is produced by the liver in response to inflammation, are proving to be good predictors of osteoarthritic progression in the knee.

If the diagnosis is uncertain or infection is suspected, a doctor may attempt to withdraw synovial fluid from the joint using a needle. There will not be enough fluid to withdraw if the joint is normal. If the doctor can withdraw fluid, problems are likely, and the fluid will be tested for factors that might confirm or rule out osteoarthritis:

Cartilage cells in the fluid are signs of osteoarthritis.
A high white blood cell count is a sign of infection.
High uric acid in the fluid is an indication of gout.

Click the icon to see an animation on gout.

Other factors may be present that suggest different arthritic conditions, including Lyme disease and rheumatoid arthritis.
In people with known osteoarthritis, researchers may look for certain factors in synovial fluid (sulfated glycosaminoglycan, keratin sulfate, and link protein) that can suggest a more or less severe condition.

Prognosis

Osteoarthritis itself is not life-threatening, but a person's quality of life can significantly deteriorate from pain and loss of mobility. The negative effects on activities and physical and mental health are significant regardless of age, educational level, or gender. Only heart disease has a greater impact on work. Five percent of those who leave the work force do so because of osteoarthritis. Unless alleviated by medication or corrected by surgery, advanced osteoarthritis can force the patient to forgo even relatively low-impact activities, such as walking. No treatment can cure osteoarthritis, and none can alter its progression with certainty, but many available therapies can relieve symptoms and significantly improve the quality of life.

Lifestyle Changes

Many doctors suggest first trying lifestyle changes to reduce stress on affected joints. Physical therapy and supportive devices can be helpful. Intensive education on how to protect and care for an osteoarthritic joint may help patients avoid multiple visits to their doctor.

Once osteoarthritis has been diagnosed, patients should reduce shock to the affected joint. Hammering away at deteriorating cartilage is likely to speed up the degeneration. People in occupations requiring repetitive and stressful movement should explore ways to reduce trauma. Adjusting the work area or substituting tasks that produce less stress on joints helps reduce shock.

Joints require motion to stay healthy. Long periods of inactivity cause the arthritic joint to stiffen and the adjoining tissue to atrophy. A moderate exercise program that includes low-impact aerobics and power and strength training has benefits for osteoarthritic patients, even if exercise does not slow down the disease progression. Exercise helps:

Reduce stiffness and increase flexibility. It may also help improve the strength and elasticity of knee cartilage.
Promote weight loss.
Improve strength, which in turn improves balance and endurance.
Reduce stress and improve feelings of well being, which helps patients cope with the emotional burden of pain.

Exercise especially helps patients with mild-to-moderate osteoarthritis in the hip or in the knee. Many patients who begin an aerobic or resistance exercise program report less disability and pain. They are better able to perform daily chores and remain more independent than their inactive peers. Older patients and those with medical problems should always check with their doctor before embarking on an exercise program.

Three types of exercise are best for people with osteoarthritis:

Strengthening exercise
Range-of-motion exercise
Aerobic, or endurance, exercise

Strengthening Exercise. Strengthening exercises include isometric exercises (pushing or pulling against static resistance). Isometric training builds muscle strength while burning fat, helps maintain bone density, and improves digestion.

Some experts encourage patients to emphasize strengthening leg muscles as a first treatment step, before using pain relievers. Patients who rely on painkilling drugs may overuse knees, which do not have muscle tissue sufficiently strong enough to protect the joints from further damage. However, some studies suggest that building up thigh muscles may worsen osteoarthritis in people whose knees are misaligned (for instance those who are "bow-legged" or "knock-kneed"). Such individuals should check with a physical therapist for the best options. Strengthening the thigh muscles is certainly protective for people who have not yet developed osteoarthritis.

Exercise, such as weightlifting, helps build muscle that is usually lost with age and puts stress on bones, helping keep them strong and healthy.

Range-of-Motion Exercise. These exercises increase the amount of movement in a joint and muscle. In general, they are stretching exercises. The best examples are yoga and tai chi, which focus on flexibility, balance, and proper breathing. In one study, older adults who practiced the gentle movement, breathing, and meditation exercises of tai chi for 10 weeks reported less pain than their peers who did not learn the technique.

Click the icon to see an image of cholesterol.

Aerobic (Endurance) Exercise. These exercises help control weight and may reduce inflammation in some joints. Low-impact workouts also help stabilize and support the joint. Cycling and walking are beneficial, and swimming or exercising in water is highly recommended for people with arthritis. (Patients with osteoarthritis should avoid high-impact sports, such as jogging, tennis, and racquetball.)

Click the icon to see an image of exercise.

In addition to exercise, manipulation of muscles and joints by a trained therapist may be helpful. In one study, patients who had a combination of physical therapy and an exercise program reported 30 - 40% improvement after only two to four visits.

Overweight patients with osteoarthritis can lessen the shock on their joints by losing weight. Knees, for example, sustain an impact three to five times the body weight when descending stairs. Losing 5 pounds of weight can eliminate 20 pounds of stress on the knee. The greater the weight loss, the greater the benefit. [See In-Depth Report #53:Weight loss and diet.]

Plant Chemicals. A large study reported significant improvement in symptoms when patients took extracts from avocados and soybeans called saponins. Another study noted that although these substances did not relieve hip pain, they did slow progression of joint deterioration. Soy has chemicals called isoflavones that may have additional benefits, such as preventing bone loss.

Fish Oil and Omega-3 Fatty Acids. Omega-3 fatty acids, which are found in fish oil, canola oil, black currant or primrose seed oils, and flax seeds, have anti-inflammatory properties and may help protect against cartilage deterioration. Supplements of omega-3 fatty acids, such as docosahexaenoic (DHA) and eicosapentaneoic (EPA) acids that are found in fish oil, are available.

Vitamin B3 (Niacin). Some research suggests that vitamin B3 may have some benefits for people with osteoarthritis.

Click the icon to see an image of the benefits of vitamin B3.

Click the icon to see an image of the sources of vitamin B3.

Calcium and Vitamin D. Calcium and vitamin D are important for strong bones. Although osteoarthritis is primarily a disease of joints, bone strength is also important, particularly in older people.

Click the icon to see an image of osteoporosis.

Many experts now recommend 1,000 mg of calcium a day for most adults and 1,200 - 1,500 mg for adolescents. Pregnant women, postmenopausal women not on estrogen therapy, and those on corticosteroids should get 1,500 mg per day; breast feeding women should get 2,000 mg/day. Because calcium supplements increase the risk for kidney stones, an upper limit of 2,500 mg is recommended.

Current guidelines recommend 400 IU of vitamin D per day and 600 IU per day after age 60. Lack of sunlight and unhealthy diets contribute to deficiencies in vitamin D. Good dietary sources include fortified milk, sardines, herring, salmon, tuna, liver, dairy products, and egg yolks. Although supplements are often necessary, vitamin D can be toxic in high doses, and no one should take more than 1,200 IU per day.

Selenium. Selenium is a trace mineral found in grains, nuts, vegetables, and some meats and seafood. Preliminary research suggests that people who do not get enough selenium in their diet may be more likely to develop knee osteoarthritis. Researchers are investigating whether selenium supplements may help protect against osteoarthritis and prevent it from worsening.

Ice. When a joint is inflamed (particularly in the knee) applying ice for 20 - 30 minutes can be effective. If an ice pack is not available, a package of frozen vegetables works just as well.

Heat Treatments. Patients afflicted with osteoarthritis of the hands can relieve pain with hot soaks and warm paraffin application. Osteoarthritis of the hip can be treated with heating pads.

Interestingly, moving to a warm climate does not seem to make much difference. According to one study, people who live in warmer places are actually more sensitive to small shifts in temperature than people who live in cold damp climates, and they experience pain as readily as their northern peers do in response to larger temperature shifts.

A wide variety of devices are available to help support and protect joints:

Splints or braces, worn while the joint is at rest or in use, help align joints and properly distribute weight. They are used most frequently to treat arthritic hands, wrists, knees, ankles, and feet. Many of these devices allow some movement within the affected joint and do not restrict nearby joints. They are usually made from lightweight metal, leather, elastic, foam, and moldable plastic with easy-to-use Velcro straps. Any brace, splint, or other device for joint protection should be custom-fitted by a physical or occupational therapist, or an orthotist. Poorly fitting or improperly used orthoses can cause more harm than good.
Using elastic supports on affected joints may benefit some people. For example, in one study, wearing insoles plus elastic straps supporting the ankle joint helped overweight women with osteoarthritis in the knee. It is important to consult with a doctor about how to use elastic supports.
Wrapping the knee with special therapeutic tape that provides support to specific parts of the joint may be effective. In one trial, patients experienced a 40% reduction in pain within a few days. They wore the tape for 3 weeks, and pain relief continued for 3 more weeks following treatment. The tape should be applied by physical therapists or other trained health professionals. Longer-term studies are needed to determine any continuous benefits.
Wearing shock-absorbing soles in shoes or orthopedic shoes can help in daily activities and during gentle exercise. Heel wedges in the shoes can sometimes help patients avoid knee replacement surgery.
A neck brace or corset may relieve back pain.
A firm mattress also often proves beneficial.
In extreme cases of back pain, lying in traction might be necessary.
Canes, crutches, or walkers offer benefits to patients with advanced arthritis.
Specially designed hip protectors, worn under the clothes, can also protect against hip fractures in elderly patients with impaired mobility who are apt to fall.

Medications

Many medications are available for relieving the symptoms of osteoarthritis. A major analysis indicated that drug therapy is generally more effective than non-drug treatments (surgery, acupuncture). However, a 2006 review of knee osteoarthritis studies found that pain-relief medications generally help only for the first 2 - 3 weeks of treatment. The following are some of the medications used in mild-to-severe cases:

Acetaminophen
Nonsteroidal anti-inflammatory drugs (NSAIDs) or COX-2 inhibitors
Capsaicin
Tramadol
Narcotic pain relievers (oxycodone, oxymorphone, or morphine)
Glucosamine and chondroitin (see Alternative and Complementary Medicine section)

Acetaminophen (Tylenol, Anacin-3, Panadal, Phenaphen, Valadol, and others) is currently the first choice for treating osteoarthritis. However, several major analyses report that acetaminophen is less effective than NSAIDs in reducing moderate-to-severe pain. Because acetaminophen has fewer side effects, most experts suggest trying this drug first, then switching to an NSAID if acetaminophen does not provide sufficient pain relief.

Side Effects. Acetaminophen is inexpensive and generally safe. It poses far less of a risk for gastrointestinal problems than NSAIDs and does not appear to increase the risk for miscarriage (as NSAIDs do), even when used regularly.

It does have some adverse effects, however, and the daily dose should not exceed 4 grams (4,000 mg). Patients who take high doses of this drug for long periods are at risk for liver damage, particularly if they drink alcohol and do not eat regularly.

The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and the stimulation of red blood cell production.

Nonsteroidal anti-inflammatory drugs (NSAIDs) block prostaglandins, the substances that dilate blood vessels and cause inflammation and pain. There are dozens of NSAIDs:

Over-the-counter NSAIDs include aspirin, ibuprofen (Advil, Nuprin, Motrin IB, Rufen), naproxen (Aleve, Naprosyn), ketoprofen (Actron, Orudis KT).
Prescription NSAIDs include ibuprofen (Motrin), naproxen (Naprosyn, Anaprox), flurbiprofen (Ansaid), diclofenac (Voltaren, Cataflam), tolmetin (Tolectin), ketoprofen (Orudis, Oruvail), nabumetone (Relafen), dexibuprofen (Seractil), indomethacin (Indocin), meloxicam (Mobic, generic).
Topical NSAIDs delivered in gels, creams, or patches do not appear to provide any long-term benefits in reducing arthritic pain. A review of clinical trial data, published in 2004, suggested that guidelines that recommend topical NSAIDs for treatment of osteoarthritis should be revised.

Many experts now recommend that patients use oral NSAIDs for only a short period of time. A 2004 review, published in the British Medical Journal, suggested that long-term use of NSAIDs does not actually reduce osteoarthritis pain and may increase patients’ risk of experiencing side effects. High dosages of NSAIDs can cause heart problems (such as increased blood pressure), kidney problems, and stomach bleeding.

In April 2005, the Food and Drug Administration (FDA) asked drug manufacturers of prescription NSAIDs to include with their products the same boxed warning used for the COX-2 inhibitor celecoxib (Celebrex). This boxed warning emphasizes an increased risk for cardiovascular events and gastrointestinal bleeding in people taking these drugs. The FDA also requested manufacturers of over-the-counter NSAIDs to revise their labels to include more specific language concerning potential cardiovascular and gastrointestinal risks. Due to its proven heart benefits, aspirin was excluded from these labeling revisions.

A 2006 comprehensive report from the U.S. Agency for Healthcare Quality and Research indicated that both NSAIDs and COX-2 inhibitors are equally effective for pain relief and pose similar risks for heart attacks. The report found that one particular NSAID, naproxen (Aleve, Naprosyn), presents less risk of heart attack for some patients. A 2006 Journal of the American Medical Association study suggested that diclofenac (Voltaren, Cataflam) may pose a higher risk for heart attack than other NSAIDs. All patients should talk to their doctors before switching any medications.

Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) is the second most common cause of ulcers, and the rate of NSAID-caused ulcers is increasing. Such ulcers are also more likely to bleed than those caused by the bacteria H. pylori. NSAID-related bleeding and stomach problems may be responsible for 107,000 hospital admissions and 16,500 deaths each year. Because there are usually no gastrointestinal symptoms from NSAIDs until bleeding begins, doctors cannot predict which patients taking these drugs will develop bleeding.

Among the groups at high risk for bleeding are elderly people, anyone with a history of ulcers of GI bleeding, patients with serious heart conditions, alcohol abusers, and those on certain medications, such anticoagulants ("blood thinners"), corticosteroids, or bisphosphonates (drugs used for osteoporosis). Proton-pump inhibitors may help to prevent and heal ulcers caused by NSAIDs. Proton-pump inhibitors include omeprazole (Prilosec), esomeprazole (Nexium), and lansoprazole (Prevacid)

Click the icon to see an image of a gastric ulcer.

Drugs for Prevention NSAID-Induced Ulcers. If you have NSAID-induced ulcers, follow these steps:

Switch to alternative pain relievers. This is the first step in preventing or healing ulcers caused by NSAIDs. If people cannot change drugs, they should use the lowest NSAID dose possible.
Try proton-pump inhibitors (PPIs). These drugs help reduce NSAID-ulcer rates by as much as 80% compared with no treatment. Brands include omeprazole (Prilosec), esomeprazole (Nexium), lansoprazole (Prevacid), rabeprazole (Aciphex), and pantoprazole (Protonix).
Try misoprostol or Arthrotec. If other drugs are inappropriate, misoprostol protects against the major intestinal toxicity of NSAIDs. It was the first drug approved for preventing NSAID-induced ulcers. It is equally, or even more, effective than some of the PPIs, but it does not heal existing ulcers and has more side effects than PPIs. Patients tend to stop using it. Arthrotec is a combination of an ulcer protective drug called misoprostol and the NSAID diclofenac. One study found that patients taking Arthrotec had 65 - 80% fewer ulcers than those who took NSAIDs alone.

Healing Existing Ulcers. A number of drugs are available to heal NSAID-induced ulcers. Treatment takes about 2 - 6 weeks. Proton-pump inhibitors are the most effective drugs. Others that may be beneficial include sucralfate or H2 blockers, such as famotidine (Pepcid AC), cimetidine (Tagamet), ranitidine (Zantac).

Coxibs inhibit an inflammation-promoting enzyme called COX-2. This drug class was initially thought to provide benefits equal to NSAIDs but cause less gastrointestinal distress. However, following numerous reports of cardiovascular events, as well as skin rashes and other adverse effects, the FDA has been re-evaluating the relative risks and benefits of this drug class. Rofecoxib (Vioxx) and valdecoxib (Bextra) have been withdrawn from the United States market. Celecoxib (Celebrex) is still available, but patients should discuss with their doctors whether this drug is appropriate and safe for them.

A newer COX-2 inhibitor, etoricoxib (Arcoxia) is approved in 60 countries but not the United States. A 2006 Lancet study indicated that etoricoxib is similar to the NSAID diclofenac in risks for heart attack and stroke. (However, diclofenac has already been shown to have a higher risk of heart attack than any other NSAID, so some experts do not find this study result reassuring.) Etoricoxib caused more high blood pressure and fluid retention (edema) than diclofenac. Etoricoxib appeared to pose a lower risk than diclofenac for uncomplicated upper gastrointestinal problems, (obstruction, perforation, bleeding, ulcers), but there was little difference between the two drugs for more serious gastrointestinal complications. In 2007, the FDA rejected an application to market etoricoxib in the U.S.

Capsaicin is a component of hot red peppers and may bring pain relief when used as a skin cream (Zostrix). This is the only skin preparation that does more than just mask pain or reduce it temporarily. Capsaicin seems to reduce a substance in the body, known as substance P, which contributes both to inflammation and the delivery of pain impulses from the central nervous system. A small amount of capsaicin must be applied to the area of inflammation about four times a day. During the first few days of use, the patient will experience a warm, stinging sensation when the cream is applied. This sensation goes away, and pain relief usually begins within 1 - 2 weeks.

Tramadol (Ultram) is a pain reliever that has been used as an alternative to opioids. It has opioid-like properties but is not as addictive. (Dependence and abuse have been reported, however.) It can cause nausea but does not cause severe gastrointestinal problems, as NSAIDs can. Some patients experience severe itching. A combination of tramadol and acetaminophen (Ultracet) is now available and provides more rapid pain relief than tramadol alone with more long-lasting benefits than acetaminophen. Side effects are the same as for each of these drugs.

Narcotics, pain-relieving and sleep-inducing drugs that act on the central nervous system, are the most powerful medications available for the management of moderate to severe pain. There are two types of narcotics:

Opiates, which are derived from natural opium (morphine and codeine).
Opioids, which are synthetic drugs. They include oxycodone (Percodan, Percocet, Roxicodone, Oxycontin), hydrocodone (Vicodin), oxymorphone (Numorphan), and fentanyl (Duragesic).

Although the use of narcotics for arthritic pain is controversial, many studies have suggested that they are rarely addictive for pain sufferers except among patients with a history of substance abuse. Some experts believe that opioids have a place in osteoarthritis treatment when milder drugs are not effective or appropriate. For example, a 2006 study suggested that a fentanyl skin patch may offer pain relief and improved function to some patients with severe knee or hip osteoarthritis who have not been helped by, or who cannot tolerate, NSAIDs or weaker opioids.

The use of such drugs may be beneficial when included as part of a comprehensive pain management program. Such a program involves screening prospective patients for possible drug abuse and then regularly monitoring those who are taking it, adjusting the dose as necessary to achieve an acceptable balance between pain relief and side effects. Common side effects include anxiety, constipation, nausea and vomiting, dizziness, drowsiness, paranoia, urinary retention, restlessness, and labored or slow breathing. Unfortunately, opioid abuse among young people is a major concern.

When pain becomes a major problem and less potent pain relievers are ineffective, doctors may resort to corticosteroid (steroid) injections, usually by administering a shot into the affected joint every 3 months. Corticosteroid shots are useful only if inflammation is present in the joint. Relief from pain and inflammation is of short duration, and this treatment is rarely used for chronic osteoarthritis. These drugs may not be as effective for women as for men.

Corticosteroids mask pain, and the patient must be very careful to avoid over-use of the affected joints. Patients are usually advised not to have more than two or three injections a year, since there is some concern that repeated injections over the long term may be harmful. A reassuring study found no greater disease progression in people who had injections every 3 months for 2 years compared to those who were given sham injections on the same schedule. Because long-term use of corticosteroids has many potentially serious side effects, steroid medications are never given orally or systemically for the treatment of osteoarthritis.

Injections of hyaluronic acid (Hyalgan, Synvisc, Artzal, Nuflexxa) into the joint -- a procedure called viscosupplementation -- is now recommended as one of the treatments for osteoarthritis. Hyaluronic acid is a naturally occurring substance in joints that acts as a lubricant for slow movements and a shock absorber for fast motions. In high amounts, it also may have anti-inflammatory effects.

Patients receive a series of three to five injections once a week.
The drug is injected into the joint.
A health care worker will apply local anesthetic because these viscous (sticky) injections require a large needle.
Patients need to avoid weight-bearing activities for about 48 hours after each shot.

Hyaluronic injections appear to be about as effective as NSAIDs and corticosteroid injections for relieving pain, at least in men, and they have no adverse effects in the stomach or intestines. One study reported that between 39 - 56% of patients were at least nearly free of weight-bearing pain up to 24 weeks after the final injection. In another study, response was judged better or much better for 87% of knees after a second course, which was administered about 8 months later. Nevertheless, a number of studies on viscosupplementation have shown little or no benefits, particularly in women, and more research is needed to determine if they are useful. Injections are also expensive. Accurate placement of the needle directly into the knee joint space is important and may be difficult, even for experienced doctors, if there is no fluid build-up in the joint. Best success rates are with a specific approach into the kneecap called the lateral midpatellar.

Side Effects. Serious adverse reactions are rare. The most common side effects, pain at the injection site and knee pain and swelling, are usually mild and temporary. More research is needed to confirm benefits and long-term risks.

Researchers are studying various drugs that may provide pain relief or stop the disease process itself:

Bisphosphonates such as alendronate (Fosamax) and risedronate (Actonel) help prevent bone loss in people with osteoporosis. They are currently being investigated for osteoarthritis as well. A 2005 study reported that risedronate may delay joint destruction in patients with knee osteoarthritis.
Lidocaine, a local anesthetic, is available in patch form (Lidoderm) and has been used specifically for herpes zoster pain. Early studies indicate that it may provide significant pain relief for osteoarthritis.
Tetracycline antibiotics, such as doxycycline, may have a role to play in treating osteoarthritis. At low concentrations, the drug reduces the production of collagenases, which are enzymes critical to disease development and progression. Initial results from clinical trials suggest that doxycycline may help delay joint space narrowing.
Licofelone is a drug that inhibits both the COX enzyme plus an inflammatory substance called lipoxygenase 5. Early trials indicate it may be effective and safer than either NSAIDs or COX-2 inhibitors.
Diacerein inhibits an inflammatory substance in arthritic joints called interleukin-1b. It has shown promise in clinical trials. A 2006 review indicated that diacerein may be slightly better than NSAIDs for pain relief.
Botulinum toxin type A (Botox) injections may provide sustained pain relief for patients with knee osteoarthritis according to research presented at the 2006 American College of Rheumatology annual meeting.
Nitric oxide increases blood flow in the mucous lining and secretions of mucus and bicarbonate. Combining nitric oxide with NSAIDs may reduce the adverse effects on the gastrointestinal tract.
Trials of gene therapies that either fight joint degradation or strengthen cartilage are in very early stages.

Alternative and Complementary Medicine

Glucosamine hydrochloride and chondroitin sulfate are natural substances that are part of the building blocks found in and around cartilage. Extracts have been used in Europe for more than a decade to reduce pain and improve mobility in patients with osteoarthritis. For many years, researchers in the U.S. have been studying whether these dietary supplements really work for relieving osteoarthritis pain.

In 2006, the New England Journal of Medicine published the results from a major trial sponsored by the U.S. National Institutes of Health. Researchers compared the effects of glucosamine and chondroitin, alone and in combination, with the COX-2 inhibitor celecoxib (Celebrex) in nearly 1,600 patients with knee osteoarthritis. The dietary supplements were also compared with placebo (an inactive substance). Patients took the assigned substance once a day for 6 months.

The results indicated that, for most patients, neither glucosamine nor chondroitin were better than placebo in relieving knee pain. However, for patients with moderate-to-severe pain, a combination of glucosamine and chondroitin was significantly more effective than the other remedies. Celebrex worked best for patients with mild pain.

The next stage of the study will evaluate whether glucosamine and chondroitin, alone and in combination, can halt the progression of knee osteoarthritis.

Research presented at the 2006 American College of Rheumatology annual meeting suggested that chondroitin may prevent joint narrowing in patients with knee osteoarthritis.

Dosage. There are no current standard recommended dosages. Patients in the GAIT trial took 1,500 mg of glucosamine and 1,200 mg of chondroitin.

Side Effects. The safety records of both substances appear excellent. Long-term effects are still unknown, but studies of up to 3 years have reported no significant side effects. However, there are some concerns that glucosamine may affect insulin and blood sugar (glucose) metabolism. Patients with diabetes should not take glucosamine without first talking to their doctors.

Oral Enzymes. People in Europe have used natural enzymes -- including bromelain, trypsin, papain, and rutin -- to treat arthritic pain. Such enzymes have been marketed alone and in combinations (Wobenzym, Phlogenzym). They are not painkillers, and any benefits derived from them may take several weeks.

Ginger (Zingiberaceae). A 2001 study of patients with knee arthritis found that an extract of ginger reduced pain while standing and after walking. By using ginger, patients were able to reduce their pain medications after 6 weeks. Side effects included mild digestive upset.

S-adenosylmethionine (SAMe). S-adenosylmethionine (SAMe, pronounced "Sammy") is a synthetic form of a natural byproduct of the amino acid methionine. It has been marketed as a remedy for both depression and arthritis. Some research suggests that it may work as well as NSAIDs for short-term treatment of osteoarthritis. Other studies suggest that it may help rebuild damaged cartilage.

Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been several reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.

Acupuncture is being increasingly used to reduce osteoarthritis pain. The technique is painless and involves the insertion of small fine needles at select points in the body. Several study reviews have found that acupuncture provides at least short-term pain relief for osteoarthritis of the knee. Other studies have suggested that acupuncture’s benefits are mainly due to a strong placebo effect, or to the psychologically beneficial effects of close contact with health care providers.

In 2004, researchers published results from an important clinical trial that studied the effects of acupuncture on nearly 600 people with osteoarthritis of the knee. The results indicated that acupuncture can relieve pain and improve function. Several 2006 studies of thousands of patients with chronic osteoarthritis pain compared acupuncture to conventional treatment (physical therapy, anti-inflammatory drugs). These studies showed positive results and suggested that acupuncture’s benefits may be sustained for up to 6 months after treatment. In any case, acupuncture appears to be a safe and beneficial addition to standard therapy for certain patients, such as pregnant women, who cannot take most pain medications.

Acupuncture, hypnosis, and biofeedback are all alternative ways to control pain. Acupuncture involves the insertion of tiny sterile needles, slightly thicker than a human hair, at specific points on the body.

Transcutaneous electric nerve stimulation (TENS) uses low-level electrical pulses to suppress pain. Patients are barely aware of the sensation. According to one study, the optimal treatment length is 40 minutes. A variant (sometimes called percutaneous electrical nerve stimulation, or PENS) applies these pulses through a small needle to acupuncture points. A review of trials reported that both methods were better than placebo (sham treatments) in treating osteoarthritis of the knee, although additional well-designed studies are needed.

Low-level laser therapy (LLLT) generates extremely pure light in a single wavelength. It does not produce heat and is painless. Some researchers are combining LLLT with transcutaneous electric nerve stimulation (TENS). Studies report widely varying results, with some showing significant reductions in pain and others reporting no effect. The differences may be due to different approaches, and standardized methods are needed to determine any benefits.

Hydrotherapy, also called spa therapy or balneotherapy, is an ancient therapy that uses bathing in mineral baths for soothing pain. Although many studies report positive results, including improved quality of life, very few have been rigorously conducted. A major analysis reported weak evidence on any real effect on pain or quality of life, but some patients may find comfort from this pleasant therapy.

Surgery

Different surgical procedures are available as a final measure to relieve pain and increase function in patients with osteoarthritis. Certain surgical procedures can help relieve pain if medications fail. Even with these procedures, however, joint replacement may still be needed later on.

Arthroscopy is performed to clean out bone and cartilage fragments that, in theory at least, may cause pain and inflammation. More than 650,000 of these procedures are done on arthritic knees each year in the U.S., and about half of patients report less pain after the procedure.

A rigorous 2002 trial, however, found that arthroscopic knee surgery was no more effective than sham surgery, (in which surgeons only pretended to operate on the knee), for relief of osteoarthritic pain or stiffness. The study, which followed patients at a Veterans Affairs hospital for 2 years, has called into serious question whether the popular procedure has any real benefits for osteoarthritis beyond what might be achieved by a placebo response. Research and debate continues on whether arthroscopy provides true benefits for those with osteoarthritis and, if so, which patients it may most help.

Click the icon to see an illustrated series detailing knee arthroscopy surgery.

When osteoarthritis becomes so severe that pain and immobility make normal functioning impossible, many people become candidates for artificial (prosthetic) joint implants using a procedure called arthroplasty. Hip replacement is the most established and successful replacement procedure, followed by knee replacement. Knee replacement, in fact, has a slightly better long-term success rate than hip replacement. Other joint surgeries (shoulders, elbows, wrists, fingers) are less common, and some arthritic joints (in the spine, for instance) cannot yet be treated in this manner. When two joints, such as both knees, need to be replaced, having the operations done sequentially rather than at the same time may result in fewer complications.

Click the icon to see an illustrated series detailing knee joint replacement surgery.

Candidates. The primary indications for surgery are pain and significant limitations of movement, including walking, that cannot be treated by less invasive therapies. Some experts suggest, however, that joint replacement should be considered earlier rather than as a last resort. They argue that patients who wait until they are severely disabled do not recover as completely as those who have the procedure earlier.

Patients who may not be good candidates are those with the following conditions:

Severe neurologic, emotional, or mental disorders
Severe osteoporosis
Other chronic medical conditions
Obesity

Surgeons often prefer to delay prosthetic implantation in younger patients, because implants wear out and they will require at least one revision procedure later on. Newer, more long-lasting materials, however, may help reduce the rate of re-operations.

Procedure Description. Although the following is mostly a description of hip replacement surgery, the principles are similar for other arthroplasties.

The surgeon removes the ball and socket joint that joins the pelvis and thigh bone (femur) and replaces it with an artificial joint (a prosthesis). It is composed of two pieces:

A cup-like device fits in the hip socket (called the acetabula), which has been hollowed out. This ball-and-socket cup is positioned to form the new joint.
A metal shaft, or stem, with a polished metal ball at the top, is inserted into the narrow center of the femur.

The prosthesis is usually made of a metal alloy and plastic. A ceramic implant may prove to last longer than other materials and be a safe option for younger patients.

There are different options available for attaching it to the adjoining bones:

A cement made of polymethylmethacrylate (usually preferred for older patients who generally have thinner bones).
So-called cementless implants, in which the prosthesis is coated with a porous material that allows bone to grow into and eventually adhere to the device. These implants are usually used for patients younger than age 65, who are likely to need repeat surgery in their lifetime.

Click the icon to see an illustrated series detailing hip joint replacement surgery.

Complications. Complications can occur, and, although uncommon, some can be life-threatening. There is a 1% chance of death within 3 months of an initial procedure and a 2.6% risk after a repeat procedure. The risks are highest in the first 3 months. Those at highest risks for complications are elderly adults, men (compared to women), African-Americans, and those with serious medical conditions.

Specific complications include the following:

Deep blood clots (known as deep vein thrombosis) and pulmonary embolism. Deep blood clots can develop in the legs after this surgery. This poses a very small risk (0.9%) for pulmonary embolism -- a dangerous condition in which the clot travels to the lungs. Anticoagulants (blood thinners) are important for preventing blood clots. These drugs include warfarin and low-molecular weight heparin. Anticoagulant therapy is given during the hospital stay and continued for several weeks at home. The patient also wears specially fitted elastic stockings to help prevent clots. Patients who are overweight are at higher than average risk for post-operative blood clots
Infection. Wound infection occurs in about 0.2% of joint replacements and requires prompt removal of the implant to treat the infection. A new prosthesis must be re-implanted at a later time. Any pre-existing infection must be treated and cured before surgery is performed. (Older women should be aware of urinary tract infections, which may require postponing surgery.) After surgery, patients should take certain precautions. For example, they should take antibiotics before invasive dental procedures or other surgery because bacteria can be introduced into the bloodstream and infect the areas around the artificial joints.
Hip dislocation. Occurs in about 3.1% of first hip procedures. The rate is much higher (14.4%) in revision operations.

Click the icon to see an image of a dislocated hip.

Pain. Thigh pain can occur after hip replacement. Porous hip prostheses are more likely to produce thigh pain than cement implants, although advanced techniques using a tapered shaft are reducing this complication.
Failure. The primary reason for implant failure is osteolysis (bone destruction) caused by long-term wear. The main source of wear is from tiny particles released from the prosthesis.
Other complications. These include uneven leg lengths, nerve damage that can cause numbness or weakness, urinary tract infections, delayed healing, and allergic reactions to the metal. Long-term, there have been rare reports of a possible autoimmune response, in which loose particles released from the prosthetic device trick certain immune system factors into attacking healthy cells. Any incidence of unexplained weight loss and fatigue may be symptoms of this uncommon event.

Rehabilitation. Aside from the surgeon's skill and the patient's underlying condition, the success rate depends on the kind and degree of activity the joint receives following replacement surgery.

The patient is urged and aided into getting out of bed and walking the day after surgery. Most hip replacement patients leave the hospital within a week and can walk with crutches within 2 - 4 weeks, recovering fully in about 3 months.

Physical therapy takes about 6 weeks to rebuild adjoining muscle and strengthen surrounding ligaments. Studies suggest that an exercise program started before surgery and resumed afterward can improve recovery. Continuous passive motion (CPM) is an effective regimen for knee replacement patients. It uses a mechanical device that slowly moves the joint through an arc of motion for an extended period of time. It is used to prevent scar tissue from developing. In one review, a combination of physical therapy and CPM were more beneficial than physical therapy alone.

Limitations After Surgery. While many patients find that joint replacement provides remarkable pain relief and restores some mobility, they need time to adjust to the artificial joint.

Limitations after hip surgery include:

Usually patients with new hips are able to walk several miles a day and climb stairs, but they cannot run.
Prosthetic hips should not be flexed beyond 90 degrees, so patients must learn new ways to perform activities requiring bending down (like tying a shoe).

Limitations after knee surgery include:

Walking distance improves in 80% of patients after knee replacement surgery, but patients still cannot run.
Only slightly more than half of patients report improvement in stair climbing. (Artificial knee joints generally have a range of motion of just 110 degrees.)

Failure Rates. Infection is a major cause of early failure and always requires revision. Improper balancing of the ligaments and other tissues surrounding the joint and resulting poor joint stability is also a common reason for failure of arthroplasties. Surgical expertise is important for avoiding this complication.

Older cement prostheses have a particularly high rate of bone loss and loosening due to cement deterioration. In general, studies report reoperation rates of over 30% after 10 years. Fortunately, advances in cement and prosthetic implants are improving the implant survival rates and reducing the need for revision procedures.

Uncemented arthroplasty using porous material has shown good results for the hip, although it may be less successful for knee replacement. In spite of short-term success, longer experience with this method suggests it may not be superior to cement prostheses. Failure of bone to grow into the porous material is a relatively common event, a problem that does not occur with cement prostheses. Some experts recommend cement implants over cementless ones for total knee arthroplasty.

A repair procedure called arthroplasty revision may be used in cases where the original transplant fails. The specific procedure depends on whether the bone defects that occurred are contained or uncontained.

Contained defects can be repaired with small bone grafts, the use of cement, or oversized cementless implants as required.
Uncontained defects are more severe and may require a large bone graft or specially constructed implants to restore bone.

If a second arthroplasty is required, the potential for complications is magnified: more bone is cut, more blood is lost, and the operation takes longer. Patients are also generally older and more vulnerable to complications.

Resection Arthroplasty. In resection arthroplasty, a false joint of scar tissue is created. This procedure is used most often in treating arthritis of the foot.

Osteotomy. If only a certain section (the medial compartment) of the knee is damaged and deformed by osteoarthritis, the surgeon may choose to perform osteotomy:

A surgeon opens the knee.
The surgeon performs a debridement (removal of damaged tissue) in the joint to eliminate the loose or torn fragments that are causing pain and inflammation.
The bone is then reshaped to remove the deformity.
The procedure may ease symptoms and slow disease progression. It is best used in heavier adults who are under 60 years old.

Hemicallotasis. Hemicallotasis is a procedure for the knee that may be a less invasive alternative to osteotomy. The surgeon attaches the knee with pins to an external frame-like device that lengthens the deformed part of the knee over several weeks. The patient is mobile during this period. Infections at the pin site are the most common complications.

Arthrodesis. If the affected joint cannot be replaced, surgeons can perform a procedure called arthrodesis that eliminates pain by fusing the bones together. The patient must understand, however, that fusing the bones makes movement of the joint impossible. Bone fusion is most often done in the spine and in the small joints of the hands and feet.

Unicompartmental Knee Arthroplasty. Unicompartmental knee arthroplasty (also called unicondylar knee arthroplasty) may be a useful procedure in cases of limited knee damage. It is recommended for relatively sedentary patients who are 60 years or older and not obese. It may relieve pain and delay the need for a total knee replacement. The procedure involves a small incision and insertion of small implants. It retains important knee ligaments, which preserve more movement than a total knee replacement.

Cartilage Transplants. Autologous chondrocyte implantation, also called chondroplasty or the Carticel approach, is used for knees damaged by injuries. In this procedure, arthroscopy is used to first remove cartilage in eroded areas. The results have been good to excellent, although long-term benefits are questionable. Whether it has any benefit for older patients with osteoarthritis is not yet known. Other cartilage transplant procedures are also under study.

Hip Resurfacing. Hip resurfacing is a surgical alternative to total hip replacement. It involves scraping the surfaces of the hip joint and femur and placing a metal cap over the bone. The procedure preserves much of the bone, so that a standard hip replacement can be done years later if needed. It may provide more stability, a faster recovery, and greater range of motion, making it a potentially good option for young, physically active patients.

Resources

www.rheumatology.org -- American College of Rheumatology
www.arthritis.org -- Arthritis Foundation
www.niams.nih.gov -- National Institute of Arthritis and Musculoskeletal and Skin Diseases
www.aaos.org -- American Academy of Orthopaedic Surgeons
www.fda.gov/cder/drug/infopage/cox2 -- FDA NSAID and COX-2 Inhibitor Information

References

Bjordal JM, Klovning A, Ljunggren AE, Slordal L. Short-term efficacy of pharmacotherapeutic interventions in osteoarthritic knee pain: A meta-analysis of randomised placebo-controlled trials. Eur J Pain. 2007 Feb;11(2):125-38.

Cannon CP, Curtis SP, FitzGerald GA, Krum H, Kaur A, Bolognese JA, et al. Cardiovascular outcomes with etoricoxib and diclofenac in patients with osteoarthritis and rheumatoid arthritis in the Multinational Etoricoxib and Diclofenac Arthritis Long-term (MEDAL) programme: a randomised comparison. Lancet. 2006 Nov 18;368(9549):1771-81.

Chou R, Helfland M, Peterson K, Dana T, Roberts C. Comparative Effectiveness and Safety of Analgesics for Osteoarthritis. Comparative Effectiveness Review No. 4. (Prepared by the Oregon Evidence-based Practice Center under Contract No. 290-02-0024.) Rockville, MD: Agency for Healthcare Quality and Research. September 2006.

Felson DT, Niu J, Clancy M, Sack B, Aliabadi P, Zhang Y. Effect of recreational physical activities on the development of knee osteoarthritis in older adults of different weights: the Framingham Study. Arthritis Rheum. 2007 Feb 15;57(1):6-12.

Laine L, Curtis SP, Cryer B, Kaur A, Cannon CP; MEDAL Steering Committee. Assessment of upper gastrointestinal safety of etoricoxib and diclofenac in patients with osteoarthritis and rheumatoid arthritis in the Multinational Etoricoxib and Diclofenac Arthritis Long-term (MEDAL) programme: a randomized comparison. Lancet. 2007 Feb 10;369(9560):465-73.

Langford R, McKenna F, Ratcliffe S, Vojtassak J, Richarz U. Transdermal fentanyl for improvement of pain and functioning in osteoarthritis: a randomized, placebo-controlled trial. Arthritis Rheum. 2006 Jun;54(6):1829-37.

McGettigan P, Henry D. Cardiovascular risk and inhibition of cyclooxygenase: a systematic review of the observational studies of selective and nonselective inhibitors of cyclooxygenase2. JAMA. 2006 Oct 4;296(13):1633-44.

Rintelen B, Neumann K, Leeb BF. A meta-analysis of controlled clinical studies with diacerein in the treatment of osteoarthritis. Arch Intern Med. 2006 Sep 25;166(17):1899-906.

Scharf HP, Mansmann U, Streitberger K, Witte S, Kramer J, Maier C, et al. Acupuncture and knee osteoarthritis: a three-armed randomized trial. Ann Intern Med. 2006 Jul 4;145(1):12-20.

Witt CM, Jena S, Brinkhaus B, Liecker B, Wegscheider K, Willich SN. Acupuncture in patients with osteoarthritis of the knee or hip: a randomized, controlled trial with an additional nonrandomized arm. Arthritis Rheum. 2006 Nov;54(11):3485-93.

Review Date:
3/19/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Child safety seats

admin — Thu, 04 Sep 2008 18:50:17 -0700

Overview

Definition
Information
References

Illustrations

Rear-facing car seat

Forward-facing car seat

HEALTH GUIDE REFERENCE FROM A.D.A.M

Definition

Child car seats; Infant car seats; Car seats

Information

Automobile accidents are one of the major causes of injury and death in children. In the United States, the law requires car seats for children under 40 pounds. For children over 40 pounds, specific laws vary by state.

Have a spouse or friend bring a car seat with you to the hospital when the child is born. You will need a car seat to bring the baby home from the hospital.

BUYING A CHILD SAFETY SEAT

It is best to use a new car seat. Used car seats often lack instructions and may have cracks or other problems that make the seat unsafe. For example, it may have been damaged during a car accident.

All car seats have expiration dates somewhere on them, usually on the bottom of the seat. Do not use a car seat past its expiration date, as the plastic may no longer be strong enough to support your child safely.

The "best" seat for you depends on your:

Child's age
Child's weight and height
Car

The seat must fit your child's size and be able to be properly installed into your car. A more expensive seat is not necessarily the safest nor easiest to use. All car seats sold in the United States must meet government safety standards.

Make sure you fill out and return the registration card that comes with a new car seat. This way, the manufacturer will contact you if the seat is recalled because of a safety problem or other defect. If you do not have a card, call the company that made the car seat and ask for one.

There are several different types of child safety seats:

Rear-facing seats
Forward-facing seats
Booster seats
Car beds
Built-in car seats

REAR-FACING SEATS

A rear-facing seat is one in which the infant faces the back of the car. Always install a rear-facing seat in the back seat of your car. This is the safest position for an infant. NEVER place a rear-facing seat in the front seat of a vehicle with passenger airbags.

There are two types of rear-facing seats:

Infant-only rear-facing seats
Convertible seats

Infant-only rear-facing seats are for babies up to about 22 to 30 pounds, depending on the specific car seat. You will need a new seat when your child gets bigger. Infant-only seats have handles that allow you to move the seat from the car to the house or other locations. Some have a base that you can leave installed in the car, so you can just click the car seat into place each time you use it.

Convertible seats are for bigger infants and toddlers under age 1 -- up to about 30-35 pounds, depending on the specific seat. The seat can be used as a rear-facing seats for younger children, and switched to a forward-facing seat on the child's first birthday if the child weighs at least 20 pounds. However, experts recommend keeping the child in a rear-facing position until he or she outgrows the weight or height allowed by the safety seat.

FORWARD-FACING ONLY SEATS

A forward-facing only seat is one in which the child sits facing the front of the car. The seat should be installed in the back seat of your vehicle. Most forward-facing only seats are for children between 20 to 40 pounds.

A combination forward-facing booster seat may be used for children between 40 to 65 pounds, depending on the specific seat. You can remove the seat's safety straps (harness) and use the booster alone, so that the car's lap and seat belts correctly fit the child.

BOOSTER SEAT

A booster seat raises your child up so that the car's lap and shoulder belts fit correctly. The lap belt should fall across the upper thighs. The shoulder belt should go across the middle of the shoulder and chest.

A booster seat is used for older children up to about 80 pounds. Some states have passed laws requiring booster seats for children up to age 8 or 80 pounds. Check your state's law.

CAR BEDS

These seats, also called flat car seats, are for premature or other special-needs babies. The American Academy of Pediatrics recommends that a health care provider looks at how your preterm baby fits and breathes in a car seat before leaving the hospital.

BUILT-IN SEATS

Some cars and vans have built-in car seats. Weight and height limits vary. You can get more details of these seats by reading the vehicle's owner's guide or calling the specific car manufacturer.

INSTALLING A CHILD SAFETY SEAT

It is important to use child car seats properly. Studies show that most people do NOT properly install car seats. The seat must fit snugly and be positioned at the proper angle. Many people install a car seat far too loosely, even though they think the seat is tight. The seat should be snug and not move more than 1 inch forward or sideways.

Follow the manufacturer's instructions for the installation and use of your specific car seat. Also, read your car owner's manual to determine the safest place to install a car seat in your car. If the instructions are unclear, call the company that made the car seat.

Contact your local police or first station for help installing your specific seat. Many have free programs to show you how to do this. To find a certified child passenger safety technician in your area go to www.seatcheck.org.

Child safety seats come with safety straps, called harnesses, which secure the child into position. Your safety seat may have a 3-point or 5-point harness system.

A 3-point harness system has two straps at the shoulder and one between the legs.
A 5-point system has two straps at the shoulder, two at the hips, and one between the legs.

The seat is secured into your vehicle using either car's seat belts or the LATCH system.

LATCH stands for lower anchors and tethers for children -- it is designed to make car seat installation easier. A child safety seat that comes with LATCH attaches to anchors in the back seat where the cushions meet and a strap called a tether, which connects the top of the safety seat to the car's frame. The car's seat belts are not used. All child safety seats and vehicles made after September 1, 2002 come with LATCH.

For more information on how to install child safety seats, see the National Highway Traffic Safety Administration web site at www.nhtsa.dot.gov. The NHTSA website also provides a list of all child safety seats recalled since 1990.

References

Quintana EC. Belt-positioning booster seats and reduction in risk of injury among children in vehicle crashes. Ann Emerg Med. 2004; 43(4): 544.

Committee on Injury and Poison Prevention; American Academy of Pediatrics. Selecting and using the most appropriate car safety seats for growing children: guidelines for counseling parents. Pediatrics. 2002;109:550-3.

Biagioli F. Proper use of child safety seats. Am Fam Physician. 2002;65:2085-90.

US National Highway Traffic Safety Administration. Misuse of child restraints. Washington, DC. US Department of Transportation, National Highway Traffic Safety Administration; 2004. DOT HS 809 671.

Review Date: 5/3/2007

Reviewed By: Leisha M. Andersen, M.D., Private Practice specializing in Pediatrics, Denver, CO. Review provided by VeriMed Healthcare Network.

A.D.A.M. Copyright

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