FitSugar

Destress On Your Big Day: Yoga for Weddings

FitSugar — Wed, 14 Feb 2007 13:00:00 -0800

For all you bride-to be's out there, I just came upon this great website called Yoga For Weddings. Basically, it's a service that offers private yoga classes for brides, grooms, and their families, focusing on de-stressing and making strong connections.

Real teachers will come to you, and give classes for the months leading up to your wedding, such as a Bride Class, Groom Class, Bride & Groom Class, Parent Class, In-Law Class, Bachelorette/Bachelor Party Class (definitely not your traditional party), Bridal Party Class, Sibling Class, Groom & Dad Class, Bride & Mom Class, Bride & Sibling Class, Groom & Mom Class, or Family Combo Class.

They offer private classes for the day or week of your wedding, and classes for after the wedding, like for your Anniversary (aww).

I love this idea. Currently, they have teachers based in New York, London, Seattle, and Miami, but they'll work with you through their network of yoga instructors, depending on where you need them. Just e-mail or call Yoga For Weddings - schedule one class or a class package, and they'll come to you, offering you peace and relaxation on your special day.

Gear Review: Modern Union Yoga Bag

FitSugar — Thu, 08 Oct 2009 15:00:03 -0700

Dealing with my yoga mat when I ride to the gym can be a pretty tricky feat. I have a bike basket that I can tie it to but it always throws me off balance. That's why I was really excited to find these messenger bags from Modern Union ($68). The bags were designed by yoga studio owners Stephanie Ofanankis and Belinda Osborne because the partners couldn't find a yoga bag that met their lifestyle needs - lucky me!

First off, I love the textiles they chose - simple, colorful, and modern. Beyond that it's a great bag to take to the gym or use on your days off. The straps on the bottom of the bag keep a yoga mat secure, and I like that there are outside pockets for a water bottle and cell phone. The inside of the bag is roomy enough to carry gym essentials or even a laptop. Inside are a bunch of smaller pockets so things don't get lost, including a key ring holder.

Most importantly these Modern Union bags make commuting on a bike so easy. There's a padded shoulder strap for comfort and a magnetic closure, which is great in case you need to get in and out of your bag quickly if you're stopped at a light. An added bonus is each bag is made out of durable cordura, meaning it won't be ripping, scuffing, or tearing on you anytime soon and it's water resistant.

Tame Tension Headache With Acupressure

FitSugar — Thu, 14 May 2009 16:00:00 -0700

When you're stressed and feel the tension mounting you can fight the inevitable headache with a little acupressure. The point at the base of your thumb, known as Union Valley, helps redirect blocked energy known as chi in Chinese medicine.

To find this tension taming spot, open your palm wide stretching all five fingers. The little mound of flesh where your thumb meets your palm is the Union Valley. Take the index finder and thumb from your opposite hand and give that spot a moderate squeeze. Hold for about 30 seconds wile breathing slowly and deeply. Repeat two to three more times, then switch hands. File this tip away for the next time you feel the beginnings of a tension headache.

Yoga Unites the Mind, Body, and Spirit

Fit Community — Thu, 12 Nov 2009 13:30:08 -0800

Barefoot chick from our Yoga Stretch and Tell community group wants to know what the practice of yoga means to you, and posted this:

I know most people do yoga to relax and tone their body and I think that is wonderful just of itself. But yoga [as defined in Sanskrit, the language of origin] actually means a union of mind, body, and spirit.

Besides the health and physical benefits does anyone also get into the spiritual aspect of yoga, or the meditative component of clearing your mind of thought? If you incorporate the spiritual dimension into your yoga or would like to talk about that part of the total yoga experience, I would enjoy hearing from you.

Have any questions or stories about yoga that you want to share? Join our Yoga Stretch and Tell community group and join the conversation! If you don't practice yoga, be sure to take a look at our other community groups - there's something for everyone.

Skip-Stop Elevators? The Wave of the Future

FitSugar — Mon, 25 Feb 2008 11:00:00 -0800

The Cooper Union plans to implement a skip-stop elevator - an elevator that only stops on certain floors - in one of its newest buildings. Along with the elevator, there will be stairways going to all floors. While I am not fully sure of why one would build such an elevator, the health nut in me likes to think that it is to try and promote folks to actually use the stairs instead of the elevator. (And don't worry there is a freight elevator for the disabled.) I've got to say, I like it. Could skip-stop elevators be the wave of the future? I mean you don't miss what you don't have, right? Would you like it if your building didn't have an elevator that took you to your floor and forced you to walk? Or is taking the stairs not your cup of tea?

Source

Food News: Restriction on Antibiotic Use in Livestock

FitSugar — Thu, 16 Jul 2009 03:00:22 -0700

After reading Michael Pollan's books - especially The Omnivore's Dilemma - and watching the new film Food Inc., I was pleased to read the news that the Obama administration is looking to restrict the use of antibiotics in livestock.

The principal deputy commissioner of food and drugs testified that feeding antibiotics to livestock to encourage rapid growth must stop, and that farmers should only be able to use the drugs with the supervision of a veterinarian. The reason behind this recommendation is that the rampant use of antibiotics has strongly influenced the development of bacteria immune to many treatments, rendering common antibiotics useless in fighting infections. This point of view has long been accepted by the medical community. According to estimates by the Union of Concerned Scientists, chickens, pigs, and cattle receive 70 percent of antibiotics used in the United States. While the American Medical Association backs the proposed restriction, it is no surprise that meat producers are opposed to it.

The Geography of Stress in the USA

FitSugar — Thu, 16 Apr 2009 03:00:00 -0700

The state that created the concept of hanging loose is unsurprisingly the least stressed-out state in the union. According to a CDC phone survey, involving 2.4 million Americans, fewer Hawaiians experience "frequent mental distress" than anywhere else in the US.

Participants were asked the total days, out of the previous 30, they would describe their mental health as being "not good." The term mental health includes stress, depression, and emotional problems. If they answered 14 days, participants were classified as having "frequent mental distress." According to the survey, only 6.6 percent of the folks living in the island state were considered frequently stressed, followed closely by South Dakotans - where only 6.7 percent of respondents reported experiencing two weeks of not-so-good mental health days.

Learn how stressed your state is when you read more.

Here's the ranking of states according to the percentage of adults experiencing frequent mental distress, and states that "tied" with the same percentage are listed together.

1. Hawaii: 6.6%
2. South Dakota: 6.7%
3. Washington DC: 7.4%
4. Kansas, Nebraska, and North Dakota: 7.5%
5. Arizona: 7.6%
6. Iowa and Montana: 7.7%
7. Illinois: 7.9%
8. Connecticut: 8%
9. Wisconsin: 8.1%
10. Minnesota: 8.2%
11. North Carolina: 8.4%
12. Alaska, Maryland, Vermont: 8.5%
13. Ohio, Wyoming: 8.6%
14. New Jersey: 8.7%
15. New Hampshire, Oklahoma: 8.8%
16. Maine, Virginia: 9%
17. Washington: 9.2%
18. Colorado, Louisiana, Pennsylvania, South Carolina: 9.3%
19. Idaho, Tennessee: 9.4%
20. Massachusetts, Georgia, Utah: 9.5%
21. New York: 9.6%
22. New Mexico, Rhode Island, Texas: 9.7%
23. Delaware: 9.8%
24. Missouri: 9.9%
25. Oregon: 10%
26. Arkansas, Florida, California: 10.1%
27. Indiana: 10.3%
28. Michigan: 10.5%
29. Alabama, Mississippi: 10.8%
30. Nevada: 10.9%
31. West Virginia: 11.2%
32. Kentucky: 14.4%

I find it sad to see that so many of the residents of my golden state are frequently stressed. How did your state fare in the survey?

Source

Protect Your Ears: iPod Safety

FitSugar — Wed, 25 Feb 2009 12:00:00 -0800

Who doesn't crank up the tunes occasionally for a rocking cardio session or to block annoying conversations on a morning commute? Unfortunately, dialing up the volume of your iPod can adversely affect your hearing.

We all know that prolonged listening to loud music can lead to hearing loss. Hearing experts say the maximum safe level for listening with ear buds or headphones is 85 decibels, but most people push the volume past competing ambient noise, which for NYC and DC is 80 decibels. This five-decibel window doesn't allow for much play when it comes to hearing your tunes. The European Union recommends a 100-decibel limit to MP3 players sold within its jurisdiction, with the purpose of decreasing associated hearing loss. But the US has no volume cap for music players, and recent tests found that many MP3 players crank all the way to 115 and 125 decibels. Hearing specialists recommend not only decreasing the volume but also the amount of time we all listen to our mighty iPods. Listening to one at maximum volume for only five minutes can begin deteriorating the delicate hair cells that line the inner ear, which decode sound waves into signals the brain interprets as sound.

I just set the volume lock on my iPod to about 80 percent of maximum volume, and I urge you to do the same with your MP3 player, whatever the brand. Easy listening might just mean hearing forever.

Source

Viral encephalitis

FitSugar — Wed, 08 Oct 2008 17:35:12 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

West Nile Virus

In 2007, 3,510 cases of West Nile virus were reported to the U.S. Centers for Disease Control. States with the highest number of reported cases included Colorado, California, and North Dakota. Of the reported cases, two-thirds were in the form of West Nile fever, and one-third were diagnosed as West Nile neuroinvasive disease (encephalitis and meningitis). However, the high proportion of neuroinvasive disease cases is due to the fact that serious cases of West Nile virus are more likely to be reported to health authorities than mild cases. In general, less than 1% of people who become infected with West Nile virus develop encephalitis.

West Nile Virus Symptoms and Diagnosis

Most people (80%) who are infected with West Nile virus do not have any symptoms. About 20% of people develop mild symptoms that include fever, headache, body aches, and nausea and vomiting. These symptoms can last from a few days to a few weeks. For the minority of people who develop neuroinvasive disease, symptoms can include high fever, headache, neck stiffness, muscle weakness, and convulsions. While West Nile neuroinvasive disease is rare, its neurological complications such as paralysis can be permanent.

Prevention

West Nile virus is carried by mosquitoes and is most common during the summer and early fall. The best way to prevent becoming infected with West Nile virus is to avoid being bitten by a mosquito. Use insect repellant when you go outside, especially during the peak mosquito hours of dusk and dawn. Remove mosquito-breeding environments (such as standing water in flower pots) from your property. Scientists are testing several different vaccines to protect against West Nile virus, but it will be many years before they are commercially available.

Introduction

Encephalitis is a rare but potentially life-threatening inflammation of the brain that can occur in people of all ages. The most common cause of encephalitis is infection by a virus. In very rare cases, encephalitis can also be caused by bacterial infection, parasites, or complications from other infectious diseases. This report focuses on viral encephalitis.

Many viruses can cause encephalitis. The West Nile virus, for example, has been responsible for high-profile outbreaks in the U.S. Most people exposed to encephalitis-causing viruses have no symptoms. Others may experience a mild flu-like illness, but do not develop full-blown encephalitis.

In severe cases, the infection can have devastating effects, including:

Swelling of the brain (cerebral edema)
Bleeding within the brain (intercerebral hemorrhage)
Nerve damage

The damage may cause long-term cognitive or physical problems, depending on the specific areas of the brain affected.

Other Viral Infections of the Central Nervous System. Viral infection and inflammation can affect multiple areas of the central nervous system, and is categorized by its location:

Meningitis: infection of the meninges (the membranes that surround the brain and spinal cord)
Meningoencephalitis: infection of both the brain and meninges
Encephalomyelitis: infection of the brain and spinal cord

Encephalitis caused by viruses in the United States generally fall into the following groups:

Arboviruses are the primary cause of acute encephalitis (sudden-onset encephalitis caused by direct infection). Arboviruses, short for "arthropod-borne viruses," are spread by mosquitoes and ticks.
Enteroviruses, such as coxsackievirus.
Herpes viruses are the other major cause of encephalitis in the U.S. This virus family includes herpes simplex, Epstein-Barr, cytomegalovirus, and varicella-zoster.
In rare cases, secondary encephalitis can develop following childhood viral diseases such as measles, mumps, and rubella.

[For more information, see the Causes section in this report.]

Encephalitis can develop shortly after an initial viral infection, or it can develop when a virus that was lying dormant in the body suddenly reactivates. Viruses are simple, but powerful infectious organisms.

The virus infects a person (host) by penetrating a cell membrane and ejecting its genetic material (its DNA or RNA) into the cell.
The viral DNA or RNA takes control of important cell processes, telling the cell to make more viruses.
The cell ruptures, releasing new viral particles that infect other cells.

There are two ways that viruses can infect brain cells:

The virus silently invades the body. There are no initial symptoms. The virus is carried by the bloodstream to the nerve cells of the brain, where they gather and multiply. Viruses that enter the brain in this manner are often widely scattered throughout the brain. This is called diffuse encephalitis.
A virus first infects other tissue and then invades brain cells. Viruses that are transmitted from other tissues usually cause focal infection, meaning they produce extensive damage in only a small area of the brain.

The brain and spinal cord comprise the central nervous system. The adult human brain weighs about 3 pounds (1.4 kilograms). There are two major parts of the brain:

The higher and larger forebrain (the cerebrum)
The lower and smaller brain stem

The cerebrum is the uppermost and largest part of the brain. It is the most highly developed section of the brain. There cerebrum has several components:

The Cerebral Cortex. The cortex is the outermost layer of the cerebrum. It is made of gray and white matter:

Gray matter is a thin sheet of nerve cells that cover the surface of the brain.
White matter is a bundle of insulated nerve fibers that underlies the cortex and makes up the core of the cerebral hemispheres.

The Hemispheres. The two hemispheres control higher brain functions, such as memory, learning, decision making, and processing input from the senses. They are each divided into four lobes, which regulate different brain functions:

Frontal lobe: This is the brain's "gatekeeper." It controls higher motor functions, including speech, and governs concentration, attention, inhibition, judgment, and personality traits.
Parietal lobe: Processes information from the senses and controls walking, posture, and head and eye movements.
Occipital lobe: Responsible for interpreting visual input from the eyes.
Temporal lobe: Responsible for interpreting auditory input from the ears. Also regulates how language is interpreted and retrieves information for memory storage.

The Basal Ganglia. The basal ganglia are clusters of gray matter within each of the lobes. They are important for coordinating voluntary muscle movement, balance, and posture.

The Limbic System. The limbic system is located deep in the cerebrum and controls interpretation of smell, instinctive behavior, emotions, and drives.

The brain stem is responsible for all vital functions. It is divided into the following areas, which are responsible for specific functions:

Medulla: sleep, breathing, heartbeat, digestion, activation of higher forebrain functions
Pons: sleep, breathing, motor control, activation of higher forebrain functions
Cerebellum: movement coordination
Midbrain: walking, posture, head, eye movement
Hypothalamus: body temperature, appetite, sexual behavior, reproductive hormones
Thalamus: communication with higher forebrain

The spinal cord extends out of the base of the skull through the vertebrae of the spinal column. It is continuous with the brain. Thirty-one pairs of nerves extend from the sides of the spinal cord to other parts of the body (the peripheral nervous system).

The meninges are three membranes that enclose the brain and spinal cord. They contain cerebrospinal fluid, which protects the central nervous system from pressure and injury.

Causes

Arboviruses

Arboviruses, including the West Nile virus, are transmitted by blood-sucking insects such as mosquitoes and ticks. Most of the time, the viral infections initially develop in birds. Insects that feed on the infected blood from a diseased bird (or reservoir ) carry the virus, and transmit it when they bite a susceptible host (such as an animal or a human). Because these insects play a role in the disease-transmission process, they are referred to as vectors.

Arboviruses multiply in blood-sucking vectors, nearly always mosquitoes. There is no evidence that these infections can be transmitted casually from one infected person or animal directly to another uninfected person without passing through a mosquito (or tick) first. (Although, a small number of West Nile virus cases have occurred through blood transfusions, organ transplantation, and possibly breast-feeding.) It should be stressed that only about 10% of people who are infected by an arbovirus develop encephalitis and that only about 1% of those infected show symptoms.

Arboviruses that cause encephalitis are primarily found in three virus families: Togaviridae, Bunyaviridae, and Flaviviridae. In the United States, the main mosquito-borne encephalitis strains are: Eastern equine, Western equine, St. Louis, La Crosse, and West Nile. Equine encephalitis causes disease in both humans and, as its name implies, horses. Powassan encephalitis is a less common tick-borne flavivirus that occurs primarily in the northern United States. Japanese encephalitis is the most common form of viral encephalitis to occur outside of the United States. It is endemic in rural areas in east, south, and southwest Asia, especially China and Korea. Venezuelan equine encephalitis is found in South and Central America.

Different arboviruses cause different forms of encephalitis. Although the overall disease is the same, there are subtle differences in symptoms and the type of brain damage they produce.


Eastern Equine Encephalitis
Virus Family	Togaviridae (genus Alphavirus)
U.S. Geographic Areas	Atlantic and Gulf coasts, in New England, and around the Great Lakes. States most affected are Florida, Georgia, Massachusetts, and New Jersey.
Symptom Onset	Symptoms appear 4 - 10 days following infection and can range from mild flu-like symptoms to full-blown encephalitis.
Incidence and Mortality Rates	The most serious of the U.S. arboviruses are fortunately rare. About 220 cases have been confirmed since 1964 with an average rate of 5 cases per year. About a third of people who contract EEE die from it. Children are more likely to survive but also to suffer complications afterward.
Age Risk Groups	Adults over age 50 and children under age 15.
Western Equine Encephalitis
Virus Family	Togaviridae (genus Alphavirus)
U.S. Geographic Areas	Farming areas in western and central Plains and Rocky Mountain states west of the Mississippi.
Symptom Onset	5 - 10 days following infection.
Incidence and Mortality Rates	Very rare. There was only one case reported between 1995 and 2000. Mortality rate is 3 - 4%; 30% of survivors have complications afterward. Most severe in children, especially those younger than 1 year. Infants may suffer permanent neurological damage.
Age Risk Groups	Infants younger than 12 months.
St. Louis Encephalitis
Virus Family	Flaviviridae (genus Flavivirus)
U.S. Geographic Areas	Takes its name from an epidemic in St. Louis, but outbreaks have occurred in wider geographic areas, especially in midwestern and southeastern states, and can occur in rural or urban areas. As of 2000, the highest numbers of total cases have been reported in Texas (970), Illinois (695), Ohio (440), Indiana (368), and Florida (379).
Symptom Onset	7 - 10 days following infection.
Incidence and Mortality Rates	Although over 4,500 cases have been reported since 1964, the average number of cases has been declining with a yearly average of only 11 cases between 1995 and 2000. Mortality rate of between 3 - 30%, with about 5% of survivors suffering complications afterward.
Age Risk Groups	Elderly adults (over age 60) are at highest risk, and the disease is most severe in this age group. Younger people usually experience mild, flu-like symptoms.
La Crosse Encephalitis
Virus Family	Bunyaviridae (genus Bunyavirus)
U.S. Geographic Areas	Occurs most frequently in upper Midwestern, southeastern (Appalachia), and mid-Atlantic states. Most cases have occurred in Ohio and Wisconsin. Unlike other encephalitis viruses which originate in birds, La Crosse encephalitis is transmitted to mosquitoes from infected chipmunks and squirrels.
Symptom Onset	5 - 10 days following infection.
Incidence and Mortality Rates	An average of 70 - 100 cases reported per year. Mortality rates are less than 1%. More common and severe in children under age 16.
Age Risk Groups	Children younger than 16 years.
West Nile Encephalitis
Virus Family	Flaviviridae (genus Flavivirus).
U.S. Geographic Areas	Cases have been reported throughout the mainland United States. In 2007, the majority of West Nile encephalitis cases occurred in Colorado, California, and North Dakota.
Symptom Onset	3 - 14 days following infection.
Incidence and Mortality Rates	In 2007, 3,510 cases of WNV were reported to the CDC, with 109 deaths. Of all the reported cases, 65% were due to West Nile fever. A third of those who contracted WNV had more severe conditions, such as meningitis and encephalitis. However, most cases of West Nile virus do not produce symptoms, and are not reported, so these numbers imply a more worrisome picture than actually exists. In fact, fewer than 1% of people who are infected with WNV go on to develop neurological disease.
Age Risk Groups	Adults over age 50.

West Nile Virus (WNV). Until 1999, the West Nile virus was generally restricted to Africa, the Middle East, southwestern Asia, eastern Europe, and Australia. It emerged in the United States with the first outbreak in New York City in 1999. WNV is now found in birds and mosquitoes in every state except Alaska and Hawaii. Human cases of West Nile encephalitis have been reported throughout the continental United States.

How WNV Is Transmitted. WNV, discovered in Uganda in 1937, circulates primarily between birds and mosquitoes and can be carried long distances by migrating birds. In a given geographic area, the appearance of the virus among birds and mosquitoes generally precedes infection in humans. WNV has infected over 110 species of birds. In addition to mosquito-to-human transmission, other causes of human infection have included blood transfusions and organ transplantation. The U.S. now uses screening tests to detect West Nile virus in donated blood and organs. There have also been cases of mother-to-child transmission during pregnancy. However, a 2006 study reported that most pregnant women who are infected with WNV deliver healthy babies. It is still not clear if WNV can be transmitted through breast milk.

Severity of WNV. About 80% of people infected with WNV will not have any symptoms. Twenty percent will develop West Nile fever (which includes fever, headache, and occasional skin rash). Less than 1% of infected people will develop neuroinvasive disease, the most severe form of WNV.

Neuroinvasive disease affects the nervous system and includes encephalitis, meningitis, and poliomyelitis. People over age 50 and those with weakened immune systems are at the greatest risk for neuroinvasive disease. The fatality rate for those afflicted ranges from 3 - 15%. Neuroinvasive disease symptoms include high fever, headache, stiff neck, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. Preliminary research is currently being conducted on vaccines to prevent WNV and antiviral drugs to treat it.

Although West Nile fever is considered to be less serious than West Nile neuroinvasive disease, an important 2006 study found that both conditions can cause long-term health complications. Researchers found that more than a year after being diagnosed with WNV, half of patients complained of neurological and psychological symptoms, including fatigue, memory problems, headaches, depression, and tremors. Patients who had West Nile fever were as likely to experience these problems as those who had WNV-associated encephalitis or meningitis.

Tick-borne encephalitis (TBE) is commonly found in many countries throughout Europe, Asia, and the former Soviet Union, but it is reported only rarely in the U.S. Powassan encephalitis is the main tick-borne encephalitis found in the United States and Canada. Cases of tick-borne encephalitis have also been reported from Rocky Mountain spotted fever, but this is a bacterial (not viral) infection.

Enteroviruses include various viruses that enter the body through the gastrointestinal tract. They account for between 10 - 20% of viral encephalitis cases. The group A coxsackievirus has been detected in infants and children with encephalitis and is among the important viruses in the class. (It should be noted that the enteroviruses are nearly as common as cold viruses and are rarely serious.) Enteroviruses can be spread through food or water contaminated by trace amounts of fecal material and through sneezing and coughing.

The herpes virus group includes a number of common infections, including herpes simplex, varicella-zoster (the cause of chickenpox and shingles), cytomegalovirus, herpes virus 6, and Epstein-Barr (EB) virus (the cause of mononucleosis). About 2,100 people are hospitalized each year from herpes-associated encephalitis. These viruses share certain features, including the capacity to cause an infection and then to go into hiding. They can lie dormant for periods of time as short as months or as long as a lifetime. In a few cases, when the viruses reactivate, they cause encephalitis. In fact, some evidence suggests that varicella-zoster, cytomegalovirus, and Epstein-Barr (EB) virus may be more common causes of encephalitis than previously thought. In most cases, however, encephalitis from these viruses occurs in people with impaired immune systems, such as people with HIV or organ transplant patients.

Herpes Simplex Virus. Herpes simplex virus (HSV) is the most common cause of encephalitis in developed countries and is responsible for about 10 - 20% of all adult cases of viral encephalitis. There are two distinct types of the herpes simplex virus: HSV-1 (commonly associated with oral herpes) and HSV-2 (which usually causes genital herpes, although HSV-1 can also cause this form). HSV-2 causes 70 - 90% of encephalitis cases in neonatal infants; the virus is transmitted through the mother's genital secretions. Although HSV-1 is the primary culprit in most adult cases of herpes encephalitis, HSV-2 may also cause a small number of these cases.

Herpes simplex encephalitis is the only effectively treatable form of encephalitis, but treatment (typically intravenous acyclovir) must be administered within the first few days of symptom onset. If left untreated, the mortality rate for patients with HSV-1 is about 70%; if treated, the mortality rate declines to 30%. The mortality rate for neonatal HSV-2 encephalitis ranges from 15 - 57%. [For more information, see In-Depth Report #52: Herpes simplex.]

Varicella-Zoster Virus. The varicella-zoster virus is responsible for both chickenpox (when the virus is called varicella) and shingles (when it is referred to as herpes zoster ). Chickenpox is the initial infection, after which the virus remains dormant, often for a lifetime. If it erupts, usually years later, is does so in the form of shingles. Encephalitis caused by varicella can occur in both children and adults and be very serious. If it occurs as a result of herpes zoster in adults, the brain inflammation tends to be mild, except in immunocompromised patients. In such cases, symptoms can appear weeks to months after an attack of shingles and resemble those of a stroke. Fortunately, encephalitis is rare with both varicella and zoster. [For more information, see In-Depth Report #82: Shingles and chickenpox (varicella-zoster virus).]

Epstein-Barr Virus. Epstein-Barr virus is the cause of infectious mononucleosis, which is most common in children and young adults. Symptoms of the disease are severe fatigue, headache, sore throat, and fever. In 1% of cases, neurological complications occur about 1 - 3 weeks after the onset of the infection. If encephalitis develops, it is almost always mild with full recovery.

Cytomegalovirus Encephalitis. Cytomegalovirus is also very common and usually mild. In immunocompromised patients, such those with AIDS, it can be dangerous, with severe complications including encephalitis.

Rabies. The rabies virus is transmitted from the saliva of an infected animal. The encephalitis it causes is virtually always fatal but is very rare in the U.S. Only one or two cases are typically reported each year, often from contact with bats.

Encephalitis Associated with Childhood Diseases. Encephalitis occurs rarely after common childhood infections, such as rubella, measles, and mumps. Immunizations have almost completely eliminated these infections in developed countries. Measles encephalitis still sometimes occurs in immunocompromised children. Rarely, influenza has caused acute encephalitis, usually in children. (Flu vaccinations are important in preventing these events.) Although there used to be concern that diphtheria-pertussis-tetanus and measles-mumps-rubella vaccines could cause encephalitis, recent research indicates that these childhood vaccines are very safe and do not increase encephalitis risk.

Adenoviruses. Adenoviruses were first identified in 1953 from infected tonsils and adenoids. The viruses can cause respiratory or gastrointestinal infections that are usually mild. In rare cases, adenoviruses can cause encephalitis or meningoencephalitis, which can be fatal in 30% of patients. Symptoms include lethargy, confusion, coma, and symptoms of meningitis (stiff neck, headache, and vomiting).

Toxoplasmosis. Encephalitis from toxoplasmosis, which is transmitted in a cat's fecal matter, results in 2,100 hospitalizations a year, which rivals herpes as the most common infectious cause of encephalitis. However, this condition causes very mild symptoms in most people. People with HIV and impaired immune systems are at risk for more severe forms. In addition, the effects on the fetus in a pregnant women infected with toxoplasmosis can be devastating. It can be treated with antibiotics, particularly those that treat parasites.

Raccoon Roundworm. Raccoon roundworm (Baylisascaris procyonis) is a large parasitic worm that lives in the intestines of raccoons. In one Wisconsin study, half the raccoons tested were infected. Humans usually become infected by ingesting the worm's eggs through accidental contact with soil, wood chips, or tree bark contaminated with raccoon feces. The worm is harmless in raccoons but can produce severe central nervous system disease, including encephalitis, in people. At least 12 severe cases have been reported in the U.S. since 1981, most in children younger than 6 years of age (who are at higher risk because of their tendency to put their fingers or other objects into their mouths). Prompt treatment with larvae-killing drugs, such as albendazole, or anti-inflammatory drugs is not consistently effective, so it is extremely important to avoid infection. Raccoons should not be kept as pets. Eliminate access to food sources, like garbage cans and bird feeders, which will attract raccoons. Raccoon nests should be sealed off while raccoons are absent. Burning any contaminated materials is the most effective method of disposal. If burning is not feasible, contaminated substances should be buried deeply in a location remote from human activity. Wearing disposable gloves, boots, and a dust mask is important. Decks, woodpiles, and other surfaces can be decontaminated with boiling water.

Other Parasitic Infections. Encephalitis may be caused by other parasitic infections, such as toxocariasis (from roundworms found in dogs and cats) or cysticercosi (from food or water contaminated with pork tapeworm eggs). These infections usually cause only chills, fever, and swelling of lymph nodes, though seizures and headaches can occur.

In very rare circumstances, encephalitis may be caused by bacterial or fungal organisms.

Acute disseminated encephalomyelitis (ADEM), also called noninfectious encephalitis, constitutes one-third of all known cases of encephalitis. It is not caused by a virus, although it most often develops in patients 2 - 3 weeks after recovery from a viral illness. (It does not affect children under 2 years old.) Damage to nerve cells in such cases is caused not by the viral infection, however, but most likely by an autoimmune reaction, in which the body's immune system attacks its own brain tissue.

Acute disseminated encephalomyelitis has been reported as a rare complication of childhood illness, including chickenpox, mumps, or measles. Vaccination reduces these risks to nearly insignificant levels. It is a complication of the rabies vaccine in one out of 30,000 cases. Nonspecific respiratory infections are now the most common causes of ADEM, but such cases are also extremely rare.

The inflammation occurs predominantly in the white matter of the brain rather than the gray matter (the usual target of infectious encephalitis). The nerve cells do not die as they do in a viral infection. Rather, the nerve cell coating (called a myelin sheath) is partially destroyed in much the same way as it is in multiple sclerosis. Indeed, the two conditions may at first be difficult to distinguish. Recurrences may occur several months to years after the initial episode.

Symptoms

Symptoms of encephalitis usually appear within 2 days to 2 weeks of exposure to the virus. In milder cases, symptoms may resemble the flu. In severe cases of full-blown encephalitis, symptoms may include:

Behavioral and personality changes
Sensitivity to light
Fever
Headache
Vomiting
Lethargy and reduced consciousness
Seizures -- uncommon with West Nile virus
Memory loss
Stiff neck and back -- accompanied by fever and headache would indicate meningitis
Confusion
Speech, hearing, and vision problems
Muscle weakness
Seizures
Partial paralysis
Loss of consciousness
Coma

Patients experiencing these types of symptoms (especially if they may have recently been bitten by a mosquito or tick of if they have lesions on the lips or genitals) should immediately seek medical treatment.

Symptoms in Infants. Infants with herpes virus encephalitis may develop lesions in the mouth, in the eye, or on the skin 1 - 45 days after birth. Other symptoms include lethargy, seizures, and changes in temperature. Their fontanels, the soft spots on their head where the skull has not yet closed, may bulge outward.

Risk Factors

Encephalitis is a rare disease, extremely uncommon in the U.S. even for people in the risk groups discussed below. Many people fall into the following categories; very few of them will ever contract encephalitis.

Encephalitis can occur at any age; increased age-associated risks depend on the type of encephalitis virus. Newborn infants are particularly at risk for herpes virus. For arboviruses, infants are most vulnerable to Western equine encephalitis. Older children and teenagers are more susceptible to Eastern equine and La Crosse encephalitis. Older and elderly adults are at higher risk for Eastern equine, St. Louis, and West Nile encephalitis.

Immunocompromised Patients

Patients whose immune systems are compromised by conditions such as HIV-AIDS, cancer therapies, or organ transplantation are more susceptible than other individuals to any form of encephalitis. Of particular concern are varicella and cytomegalovirus encephalitis which tend to be more common and deadly in these patients than in the normal population.

U.S. Geographic Regions. The primary risk factor for arbovirus encephalitis is living in areas of possible exposure to virus-carrying mosquitoes. Most viral outbreaks occur in rural or farming areas, but they can also occur in cities. While some forms of arbovirus encephalitis are limited to specific geographical regions, the West Nile virus has become endemic throughout the mainland United States. [See Common Forms of Mosquito-Borne Encephalitis table for more detailed regional information.]

Seasonal Risks. Transmission of arboviruses correlates with the mosquito season and is highest during the months of July through September (late summer through early fall). The ideal conditions for mosquito breeding are a wet spring followed by a hot, dry summer.

Few people in the world have not been infected with at least one of the herpes viruses. Most of these viruses are easily transmitted in body fluids, including from saliva or droplets after people exhale or sneeze. Infants can contract herpes simplex virus from an infected mother during delivery, which can have very serious consequences. [For more information, see In-Depth Report #52: Herpes simplex.]

Prognosis

In most cases of arbovirus infection, symptoms are mild, last 3 - 5 days, and resolve without becoming serious. In fact, the infection is generally unrecognized as anything other than a mild flu.

Prognosis for severe encephalitis depends on many factors, including the following:

Age of the patient -- worse outcomes for infants under age 12 months and adults over age 55
Immune status
Preexisting neurological conditions
Virulence of the virus

In severe cases of encephalitis, the swelling of the brain inside the skull places downward pressure on the brain stem. The brain stem controls vital functions, such as respiration and heartbeat, and if the pressure becomes too severe, these vital functions can cease and cause death.

Coma is a common symptom in patients with severe encephalitis, but does not necessarily predict a fatal or severe outcome. In one study of Eastern equine encephalitis, some survivors averaged 5 days in a coma and had no or only mild-to-moderate complications afterward. One patient was in a coma for 9 days and had only mild complications afterward.

Survivors of encephalitis commonly experience neurologic consequences, which can be long-term and even permanent. The degree and type of brain damage can vary from mild-to-severe and from focal (in one part of the brain) to multifocal (several parts of the brain) to diffuse (throughout the brain).

The location and severity of the infection largely determines the pattern of brain damage and therefore its effects, which can be:

Physical (muscle control)
Behavioral and emotional (personality changes)
Cognitive (memory, speech)
Sensory (vision, hearing)
Some patients who have memory problems and personality changes afterward describe their condition as being an "invisible disease." They appear to be normal to others, but they are plagued with forgetfulness and lapses in attention that have a considerable effect on the quality of their daily lives. Helpful support groups are now available on the Internet.

Diagnosis

In many cases, the symptoms of encephalitis are too similar to aid the doctor in differentiating among the many causes of brain inflammation. The primary objective in diagnosing viral encephalitis is to determine if it is caused by:

Arboviruses or other viruses that can be managed only by relieving symptoms
Herpes simplex or other conditions that are potentially treatable

If the doctor suspects encephalitis, a scanning technique is often the first diagnostic step. Computerized tomography (CT) or magnetic resonance imaging (MRI) scans may show the extent of the inflammation in the brain and help differentiate encephalitis from other conditions. MRI can detect injuries in parts of the brain that suggest infection with herpes virus at the onset of the disease, while CT scans cannot.

Electroencephalogram (EEG), which records brain waves, may reveal abnormalities in the temporal lobe that are indicative of herpes simplex encephalitis.

When encephalitis is suspected, a sample of cerebrospinal fluid is taken using a lumbar puncture, which involves inserting a needle between two vertebrae in the patient's lower back. The sample is taken to count white blood cells and identify specific blood cell types, to measure proteins and blood sugar levels, and to determine spinal fluid pressure. Doctors use cerebrospinal fluid to test for herpes simplex encephalitis and to look for the presence of antibodies to the West Nile virus. While cerebrospinal fluid tests may help diagnose encephalitis, they cannot provide information on how severe the disease will be.

Blood tests are used to test for West Nile virus and other arbovirus infections.

If necessary, tiny samples of brain tissue are surgically removed for examination and testing for the presence of the virus. Tissue is prepared using staining techniques and then viewed under an electron microscope. In a few cases, the viruses in brain cells are able to be cultured; that is, the viruses can actually be made to replicate in samples. A brain biopsy is the gold standard for diagnosing rabies.

Treatment

With the exception of herpes simplex and varicella-zoster encephalitis, the viral forms of encephalitis are not treatable. The primary objective is to diagnose the patient as soon as possible so they receive the right medicines to treat the symptoms. It is very important to lower fever and ease the pressure caused by swelling of the brain.

Patients with very severe encephalitis are at risk for body-wide (systemic) complications including shock, low oxygen, low blood pressure, and low sodium levels. Any potentially life-threatening complication should be addressed immediately with the appropriate treatments.

Since it is difficult to determine the cause of encephalitis, and rapid treatment is essential, it is common to give the patient medication for the symptoms that respond to therapy without waiting to determine the cause of the illness.

Some experts advise immediately administering intravenous acyclovir, the standard treatment for herpes simplex encephalitis, to all patients whose symptoms indicate encephalitis.
Corticosteroids, which reduce inflammation, may also be administered immediately.
Antibiotics, which attack bacteria but not viruses, are used in case the cause of the symptoms is bacterial meningitis.

All encephalitis treatments are aimed at reducing symptoms.

Seizures may be prevented by using fosphenytoin (Cerebyx).
Seizures may be treated with intravenous lorazepam (Ativan).
Sedatives may be prescribed for irritability or restlessness.
Simple pain relievers may be used for fever and headache.
In patients who are otherwise stable, the only other treatment measures are to keep the head elevated and monitor the patient's status.

Intravenous acyclovir is the treatment of choice for encephalitis caused by herpes simplex virus (HSV) or varicella-zoster virus. Treatment must be initiated within 2 days of symptoms for the best outcome. In nearly all cases, the virus clears within 2 weeks of treatment. If it does not, medications are continued for another 2 weeks. In rare cases, surgical measures may be needed to relieve the buildup of pressure in the brain.

Acyclovir is usually administered in the hospital. However, some patients may be safely treated with intravenous medications at home after the first few days with close monitoring by a health professional. Valacyclovir and famciclovir may be used for the treatment of non-life-threatening HSV infection.

About 25% of patients who have been successfully treated for herpes encephalitis have a relapse. Early diagnosis and treatment may help reduce this risk. Doctors are investigating if a 3-month course of oral valacyclovir will improve remission rates after a patient completes treatment with intravenous acyclovir. Foscarnet (Foscavir), another powerful antiviral drug known as a pyrophosphate analogue, may be useful for herpes simplex viral strains that have become resistant to acyclovir.

No other drugs have been effective for treating arboviruses, including West Nile virus. A number of drugs used to treat other virus infections are being investigated. They include ribavirin (an antiviral drug used to treat influenza), interferon alfa 2a (Roferon-A) and other interferons, immunoglobulin G, and glycyrrhizin (a compound in licorice root with anti-viral activity). Researchers with the U.S. National Institutes of Health are investigating Omr-IgG-am, a blood-derived product that contains WNV antibodies, which can be given intravenously.

ADEM is usually treated with high-dose intravenous methylprednisolone, a powerful anti-inflammatory drug known as a corticosteroid. Intravenous immunoglobulin (IVIG), alone or in combination with methylprednisolone, is also showing promise in certain patients, including children with severe ADEM.

Vaccinations

Certain vaccinations can help prevent the diseases that can lead to encephalitis.

Measles used to be a very common childhood disease. In about 1 in 1,000 patients it can lead to encephalitis or death. The risk for these severe complications is highest in the very young and very old. Aggressive vaccination programs have reduced the incidence of measles in the U.S. to fewer than 100 cases a year. Rarely, patients who receive the live-measles vaccine develop encephalopathy (brain damage), but the risk is far lower than brain problems occuring from the disease itself.

Herpes zoster, or shingles, is a reactivation of the varicella virus, which causes chickenpox. Children (and adults who do not have a history of infection and who lack evidence of immunity) should receive 2 doses of the chickenpox vaccine. In 2006, a vaccine for shingles became available for adults age 60 years and older. [For more information, see In-Depth Report #82: Shingles and Chickenpox.]

Researchers are investigating a number of vaccines against the flavivirus family of arboviruses.

A vaccine (JE-VAX) is currently available for Japanese encephalitis. In travelers, it is only recommended for those visiting rural areas in high-risk Asian countries for more than 30 days. These countries include China, Korea, India and neighboring areas, and Southeast Asia. The disease may occur with lower frequency in Japan, Taiwan, Singapore, Hong Kong, and eastern Russia. A new type of Japanese encephalitis virus vaccine is currently in clinical trials.

Another type of vaccine (FSME-IMMUN) is used to prevent tick-borne encephalitis (TBE) in travelers visiting regions where this type of encephalitis is prevalent. TBE is found mainly in Eastern Europe, China, North Africa, and Russia. This vaccine is available in many European countries, but it is not yet approved in the United States.

Two types of vaccines, chimeric and DNA, are under investigation for West Nile virus, but it will be several years before these vaccines could become commercially available.

Anyone exposed to bats, or the secretions of an animal suspected of having rabies, should be evaluated for post-exposure rabies vaccine. Exposed individuals may also receive immune globulin unless they were previously vaccinated. Local health authorities are generally consulted. When the saliva of a potentially infected animal is exposed to an open wound or mucous membrane, treatment is generally warranted. However, the need to administer rabies immunization or immune globulin after saliva exposure to intact skin is not as clear. Veterinarians and animal handlers should be vaccinated. This does not eliminate the need for treatment if they are exposed to rabies, but it reduces the intensity of the treatment. Side effects of these shots include:

Pain
Redness
Headache
Stomach pain
Nausea
Dizziness
Muscle aches
Swelling at the injection site

Allergic response can occur after the first shot and as many as 21 days after a booster shot. Rare cases of neurological disorders have been reported that cause pain and paralysis in the legs and arms, which clear up in about 12 weeks.

Prevention

The risk for mosquito-born infections is highest between dusk and dawn, when mosquitoes feed. A good insect repellent is very helpful in reducing the risk for vector-borne disease. The most complete personal protection program for adults and most children is to apply the insect repellant DEET to the skin, and also permethrin to clothing and other surfaces.

DEET. Most insect repellents contain the chemical DEET (N,N-diethyl-meta-toluamide), which remains the gold standard of currently available mosquito and tick repellents. DEET has been used for more than 40 years and is safe for most children when used as directed. Comparison studies suggest that DEET preparations are the most effective insect repellents now available.

Concentrations range from 4% to almost 100%. The concentration determines the duration of protection. Experts recommend that most adults and children over 12 years old use preparations containing a DEET concentration of 20 - 35% (such as Ultrathon), which provides complete protection for an average of 5 hours. (Higher DEET concentrations may be necessary for adults who are in high-risk regions for prolonged periods.)

Never use DEET products should on infants younger than 2 months. According to the Environmental Protection Agency (EPA), DEET products can safely be used on all children age 2 months and older. The EPA recommends that parents check insect repellant product labels for age restrictions. If there is no age restriction listed, the product is safe for any age. The American Academy of Pediatrics recommends that children use concentrations of 10% or less; 30% DEET is the maximum concentration that should be used for children. When deciding what concentration is most appropriate, parents should consider the amount of time that children will be spending outside, and the risk of mosquito bites and mosquito-borne disease.

When applying DEET, take the following precautions:

Do not use on the face, and apply only enough to cover exposed skin on other areas.
Do not over apply, and do not use under clothing.
Do not apply over any cuts, wounds, or irritated skin.
Only parents or an adult should apply repellent to a child. They should first put DEET on their own hands and then apply it to the child. They should avoid putting DEET not only near the child's eyes and mouth but also on the hands (since children frequently touch their faces).
Wash any treated skin after going back inside.
If using a spray, apply DEET outdoors -- never indoors. Spray repellents should not be applied directly on anyone's face.

Other Insect Repellent Products. In 2005, the U.S. Centers for Disease Control (CDC) added two new mosquito repellents to its list of recommended products: Picaridin and oil of lemon eucalyptus.

Picaridin, also known as KBR 3023 or Bayrepel, is an ingredient that has been used for many years in repellents sold in Europe, Latin America, and Asia. A product containing 7% picaridin is now available in the United States. Picaridin can safely be applied to young children and is also safe for women who are pregnant or breast-feeding. According to the CDC, insect repellents containing DEET or picaridin work better than other products.

In scientific tests, oil of lemon eucalyptus, also known as PMD, worked as well as low concentrations of DEET. However, oil of lemon eucalyptus is not recommended for children under the age of 3 years.

Permethrin is an insect repellent used as a spray for clothing and bed nets, which can repel insects for weeks when applied correctly. Electric vaporizing mats containing permethrin may be very helpful. A permethrin solution is also available for soaking items, but it should never be applied to the skin. Side effects from direct exposure may include mild burning, stinging, itching, and rash. In general, however, permethrin is very safe and its use may even reduce child mortality rates from malaria. People allergic to chrysanthemum flowers or who are allergic to head-lice scabicides should avoid using permethrin.

Eliminate Sources of Standing Water. Currently, the only proven method for reducing mosquito populations is to eliminate sources of standing water.

Look for any source of standing water, where mosquitoes can breed. For example, discard any rubbish with standing water, such as old tires, cans, and bottles. (Even bottle caps can breed mosquitoes.) Turn over wading pools and wheelbarrows when not in use. Change bird bath water every 3 - 4 days. A product called Mosquito Dunk can be used to prevent breeding in standing water.
Swimming pools and hot tubs should be clean and chlorinated or drained and covered if not in use.
Clean vegetation and debris from the edges of ponds.
Keep gutters clean and unclogged.

Mosquito Traps. Mosquito traps use various methods for repelling or attracting and trapping the insects. Effective traps are expensive, and they usually require electricity or propane, which adds to the cost. Use mosquito trap machines only outdoors. While many traps can draw in significant numbers of mosquitoes, they have limitations. Do not rely on them for sole protection.

All baits should aim to attract the female mosquito, which is the primary transmitter of the viruses. However, different baits may be more or less effective. Some may even attract one species and not others. For example, a comparative study of three traps that used similar attractants found that after 20 hours, the Magnet Liberty and Mosquito Trap MK01 attracted 75% of mosquitoes in a single area, while the Sonic Web had attracted only 25%. However, all three traps tended to attract twice as many Aedes mosquitoes (which carry La Cross and Eastern Equine encephalitis) as the Culex (which transmits West Nile and St. Louis Encephalitis).

Bug Zappers. Insect light traps (commonly called bug zappers), which attract and electrocute insects, may actually spread viruses and bacteria that are on the insects. They are also not very effective for killing female mosquitoes.

Encouraging Natural Defenders. Some attempts have been made to control mosquito populations with natural defenders, including building bat and bird houses to attract natural predators or growing certain insect-repellent plants.

Citronella Candles. Burning citronella candles reduces the likelihood of bites. (Indeed, burning any candle helps to some extent, perhaps because the generation of carbon dioxide diverts mosquitoes toward the flame.)

Your home environment, personal hygiene, and what you wear can also help reduce your risk for mosquito bites:

Wear trousers and long-sleeved shirts, particularly at dusk. One survey suggested that this measure may significantly reduce the incidence of mosquito-born disease.
Sleep only in screened areas.
Air-conditioning may reduce mosquito infiltration. Where air-conditioning is not available, fans may be helpful. Mosquitoes appear to be reluctant to fly in windy air.
Don't wear perfumes.
Cover up bare skin after dusk.
Wash your hair at least twice a week.

Public health measures are the best methods for controlling mosquitoes.

Spraying. Local areas that experience outbreaks of encephalitis from mosquitoes usually have a spraying program.

Insecticides containing synthetic pyrethroids (permethrin, resmethrin, and sumithrin) are generally recommended by consumer groups as being the most effective and the least toxic to people (although they are toxic to fish and bees).
Malathion and naral -- another pesticide -- are organophosphates and approved for spraying mosquitoes. Malathion specifically has been widely used in a number of areas. Organophosphates, however, can have toxic effects on the nervous system. Some people, for example, have reported being sick after exposure to Malathion. In addition, there is a risk that mosquitoes will develop resistance to it.

Report Dead Birds. Dead birds may be indicators that the West Nile virus has reached a specific region. Report any dead birds to your local public health authorities. You should never touch a dead bird with your bare hands.

Resources

www.cdc.gov -- The U.S. Centers for Disease Control (CDC)
www.cdc.gov/ncidod/dvbid/arbor -- CDC website for arboviruses
www.cdc.gov/ncidod/dvbid/westnile -- CDC West Nile virus website
www.ninds.nih.gov -- National Institute of Neurological Disorders and Stroke
www3.niaid.nih.gov -- National Institute of Allergy and Infectious Diseases
www.mosquito.org -- American Mosquito Control Association
www.npic.orst.edu/wnv -- National Pesticide Information Center's West Nile virus resource guide

References

Bleck TP. In: Goldman L and Ausiello DA, eds. Cecil Medicine. 23rd edition. Saunders; 2007.

Modlin JF. In: Goldman L and Ausiello DA, eds. Cecil Medicine. 23rd edition. Saunders; 2007.

Nath A, Berger JR. In: Goldman L and Ausiello DA, eds. Cecil Medicine. 23rd edition. Saunders; 2007.

Whitley RJ. In: Goldman L and Ausiello DA, eds. Cecil Medicine. 23rd edition. Saunders; 2007.

Review Date:
1/26/2008
Reviewed By:
Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

A.D.A.M. Copyright

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-2009 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

adam.com

Vitamins

FitSugar — Wed, 08 Oct 2008 17:35:00 -0700

In This Report

Highlights
Introduction
Carotenoids
Phytochemicals
Healthy Foods
Dietary Health Benefits
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Cancer

Growing evidence suggests that vitamins and micronutrients, especially from foods, may play important roles in the prevention or treatment of certain cancers:

One study found that the risk of prostate cancer risk dropped as consumption of vegetables high in vitamin C, such as broccoli and bell peppers, rose.
A diet high in cruciferous vegetables has been found to reduce the risk of kidney cancer; low consumption of cruciferous vegetables increases the risk.

On the other hand, high amounts of folic acid (a B vitamin) may be associated with colorectal cancer, and beta-carotene supplements are associated with increased lung cancer risk in smokers and people exposed to asbestos.

Macular Degeneration

In 2007, the National Eye Institute recommended that people with intermediate or advanced macular degeneration in one eye take a vitamin formula shown to reduce the risk of macular degeneration in the other eye by 25%. The formula contains vitamin C, vitamin E, beta-carotene, and zinc.

Osteoporosis

Vitamin K is widely used in Japan to treat osteoporosis, and studies suggest it also may be effective in treating rheumatoid arthritis.

Heart Disease

Although people with high levels of homocysteine are prone to developing blood clots in their arteries and veins, a 2007 study found that lowering homocysteine with B vitamins and folic acid does not reduce the incidence of deep vein thrombosis (DVT). A 2007 trial in adults with stable coronary artery disease found that lowering homocysteine levels 33% with folic acid and other B vitamins had no effect on arterial inflammation, meaning that lower levels were unlikely to offer protection against heart attack or stroke.

Introduction

Vitamins do not share a common chemistry, but they do share certain characteristics. They are all organic nutrients that are necessary in small amounts for normal metabolism and good health. Your diet or supplements provide most vitamins. The body can manufacture only three vitamins (D, K, and the B vitamin biotin) from nondietary sources. Unlike carbohydrates, fats, and proteins, vitamins are not sources of energy. Instead, vitamins are chemical partners for the enzymes involved in the body's metabolism, cell production, tissue repair, and other vital processes.

Vitamins are either fat soluble or water soluble. The fat-soluble vitamins, which include A, D, E, and K, are absorbed by the body using processes that closely parallel the absorption of fat. They are stored in the liver and used up by the body very slowly. The water-soluble vitamins include C and the B complex vitamins. The body uses these vitamins very quickly. Excess amounts are eliminated in urine.

The Recommended Daily Allowance (RDA) for vitamins, set by the Food and Nutrition Board of the National Academy of Sciences-National Research Council, has been used for years as a guide for determining the amount of vitamins needed for a healthy diet. The RDA refers to an estimate of the average daily requirement. It is not completely adequate, however, for informing people about the amounts of vitamins they may need.

The RDA is gradually being enhanced using a new standard called the Dietary Reference Intake (DRI). The DRI is based on the following ratings, which will eventually appear on labels:

The recommended daily allowance (RDA). This is the current rating on most vitamins.
The estimated average requirement (EAR). This is the amount adequate for 50% of all people, which will be put on labels when it can be calculated.
Adequate intake (AI). This is an amount that will be used if there is insufficient data to calculate the EAR.
Tolerable upper intake level (UL). This is the maximum dose likely to be safe in nearly all individuals. It will be included on labels if this amount is known.

Food and supplement labels now typically list the Daily Value (DV). This is the percentage of the amount of a nutrient that experts believe a person needs in their daily diet. On food labels it is usually based on one serving size for a person who takes in 2,000 calories a day.

Regulation of dietary supplements by the U.S. Food and Drug Administration (FDA) is a complex issue.

Labels on vitamins and other dietary supplements now include nutrient information and list all ingredients, including identifying parts of plants from which ingredients may be taken. Unlike the labels for drugs, however, labels for vitamins and supplements may not claim to prevent or treat any specific disease. Labels for vitamins and supplements include one of the following:

Health claim -- description of how the substance may reduce the risk of a health-related condition
Nutrient claim -- description of the amount of the nutrient in the product or
Structure or function claim -- description of how the product may affect organs or systems of the body, without claiming to prevent or treat specific disease

The quality of dietary supplements depends on the manufacturer and is not ensured by FDA. The U.S. government does not require that supplements be standardized, meaning that the amounts or quality of nutrients may vary depending on the batch. So, more expensive supplements are not necessarily better than the less expensive ones. Government regulations are in the process of catching up to the boom in the supplement industry. In the meantime, some companies voluntarily adhere to rigorous quality controls, while others do not.

The U.S. Pharmacopeia (USP), an independent organization that sets quality standards for drugs, has also implemented standards for vitamins. Consumers may look for the USP label on products of companies that adhere to these standards. USP verification means the following:

What is in the bottle matches what is listed on the label.
There are no harmful levels of contaminants.
The supplement will be absorbed properly into the body.
It has been produced according to good manufacturing standards.

Before selling any supplement introduced after 1994, manufacturers must submit information as to why the product is considered safe for people. The FDA may refuse to allow it on the market if it finds the evidence insufficient. The FDA does not require manufacturers to provide any scientific evidence that dietary supplements are safe and effective before a product is sold (unlike drugs, which must be proven both safe and effective through clinical trials). If a supplement causes side effects in people once it is for sale, the government may place restrictions on the supplement or withdraw it from the market. The FDA may also withdraw products from the market if their labels are misleading or false.

About 30% of Americans take at least one vitamin or mineral supplement daily. In a large study that examined the death rates of 11,000 people, however, there was no difference in mortality rate between those who took vitamin supplements and those who didn't. Most people who have a healthy diet do not need vitamins, but there are some exceptions.

Pregnant and Breast-Feeding Women. Women who are pregnant or who are breast-feeding generally need additional vitamins. Vitamins B6, B12, and folic acid are particularly important. Women who are vegetarians must be sure to avoid deficiencies, which can harm their offspring. Folic acid reduces the risk for neural tube defects and possibly facial abnormalities, such as cleft palate. Studies also show that low folate levels during pregnancy are associated with low birth weight, a risk factor for the development of cardiovascular disease in adulthood. Multivitamins that contain folic acid also appear to be somewhat protective. A woman's best approach is to take extra folic acid plus multivitamin supplements (which have additional benefits), starting them before becomming pregnant.

The human body stores several years' worth of vitamin B12, so nutritional deficiency of this vitamin is extremely rare. Although, people who follow a strict vegetarian diet and do not consume eggs or dairy products may require vitamin B12 supplements.

Pregnant women with healthy diets may have low folate levels and need to take supplements. Requirements are as follows:

The recommended daily allowance (RDA) for folic acid prior to conception and during pregnancy is 400 mcg.
During breast-feeding 260 - 280 mcg is recommended.

The following vitamins may have some value for pregnant women:

Choline, another vitamin B, is also essential for pregnant (450 mg) and nursing women (550 mg). Choline plays a key role in brain development. Not getting enough during pregnancy can lead to memory and cognitive defects in the baby. Choline supplements can also lessen the cognitive defects of prenatal alcohol exposure.
Vitamin B6 may help improve morning sickness.
Vitamin C may reduce the risk of urinary tract infections during pregnancy.
Vitamin D may help prevent preeclampsia.
One study also suggested that if pregnant women took vitamin K supplements, their infants might not need the required injection of this vitamin after birth, but supplements of vitamin K during pregnancy are not currently recommended.

Some women have low vitamin A reserves in their liver. It is important to note, however, that too much vitamin A significantly increases the risk for birth defects. Daily amounts of 10,000 IU (international units) of vitamin A in supplements and food (an amount not far above the RDA level) can pose a danger. Experts recommend that pregnant women take in no more than 8,000 IU per day and avoid eating liver.

Infants and Children. Infants who are breast-fed by healthy mothers receive enough vitamins except, in some cases, vitamins K and D. Human milk has low levels of K, and the newborn's immature intestinal tract may not produce enough of the baby's own supply. Most babies are given an injection of this vitamin at birth. Infants being breast-fed by malnourished women or those who lack sufficient exposure to sunlight may be deficient in vitamin D. In these cases, supplements of 200 - 300 IU are recommended. Formulas are required to contain sufficient vitamins and minerals. One study suggests that vitamin supplements for infants under 1 year of age may help protect them from developing type 1 diabetes later on. Beyond infancy, most American children receive all the vitamins they need from their diet unless they are living in severely deprived circumstances.

Smokers. Smoking interferes with absorption of several vitamins, importantly vitamins C and D. In one study nearly 25% of female smokers and 31% of male smokers were deficient in vitamin C. Smoking can interfere with the metabolims of vitamin D, resulting in poor muscle function. Taking high doses of antioxidant vitamins, however, may actually be harmful in smokers, especially beta carotene. Instead of taking supplements, most smokers should be sure their diets are rich in fresh fruits and vegetables and whole grains. Of course, smoking cessation is the most important intervention of all.

Click the icon to see an image of sources for vitamin C.

Alcoholics. Alcoholics often suffer from multiple vitamin deficiencies. The most dangerous deficiencies are from vitamins B1 (thiamin), folic acid, B6 (pyridoxine), B2 (riboflavin), and vitamin C. Low levels of B6 are associated with increased risk of colorectal cancer in men who drink large amounts of alcohol.

Overweight Adults. Overweight and obesity causes many problems that often result in metabolic syndrome or type 2 diabetes. Evidence suggests that isoflavones can help regulate cholesterol levels and reduce body weight and fat mass. Because some medications used to control blood sugar levels reduce folic acid and vitamin B12, some people may need vitamin supplements.

People Who Have Had Gastric Bypass Surgery. Vitamin deficiency is a recognized complication of gastric bypass surgery. Women, African-Americans of both sexes, and adults who have had laparoscopic Roux-en-Y bypass surgery are at highest risk. The deficiency is treated with water-soluble vitamin supplements.

Strict Vegetarians. Strict vegetarians need supplements of vitamin B12, unless they get enough of it from fortified cereals and other grain products.

Dieters and Vegetarians. People on weight-reduction diets with less than 1,000 calories a day should probably take a multivitamin and should also check regularly with a physician.

Vegetarians may need riboflavin, vitamin B12, and vitamin D supplements. Vegans, who do not eat dairy or eggs as well as meat, may be at further risk for vitamin A deficiencies if they do not also have plenty of dark colored fruits and vegetables. Those who eat eggs and dairy products need only watch their iron levels.

Deficiencies in vegetarian children may be particularly harmful. (One study, for example, reported that adolescents who had been on macrobiotic diets before age 6 and were deficient in vitamin B12 scored lower on psychological tests.) Pregnant and breast-feeding women who are vegetarians must be sure to have sufficient vitamins. Of special note, maternal deficiencies in vitamin B12 may cause delayed growth and neurologic problems in their newborns.

Click the icon to see an image of sources for vitamin D.

Older Adults. Deficiencies of vitamins and important minerals have been observed in almost a third of elderly people. Often their dietary habits slip and they fail to eat balanced meals regularly. Multiple drug regimens may prevent absorption of some vitamins. Elderly people, particularly if they are not exposed to sunlight, may be deficient in vitamin D. They also may have low levels of important B vitamins. (Older adults showing signs of dementia should be checked for B12 deficiencies as well as other disorders causing mental disturbances.) One study reported that the immune systems of elderly people may benefit from higher levels of vitamin E than the daily recommended dosage. It should be noted, however, that metabolism slows down as a person ages, and in elderly people it takes the liver longer to eliminate drugs and vitamins from the body. The effect of some vitamin supplements, therefore, may be intensified. Dosage levels of vitamin A, for instance, which might be harmless in a younger adult, could be toxic in an elderly patient. Nevertheless, experts are increasingly recommending extra vitamin and mineral supplements for older people.

People Who Need to Avoid Sunlight. People who need to avoid sunlight or are housebound, and whose diet is low in foods that contain vitamin D should take supplements. People with darker skin are at higher risk for deficiencies than those with whiter skin. (Note: vitamin D is toxic in high doses, and no one should exceed the recommended daily intake of vitamin D except under the direction of a physician.)


Benefits	Essential for growth, bone development, night vision, reproduction, and healthy skin.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	Vitamin A RDA and Upper Limit (when toxicity is risk) are the following: For children: 1,000 IU ages one to three (upper limit is 2,000 IU); 1,333 IU ages 4 - 8 (upper limit is 3,000 IU); and 2,000 IU for 9 - 13 (upper limit is 5,665 IU). For nonpregnant women: 2,330 IU ages 14 through adulthood. (Upper limit is 9,335 IU for ages 14 - 18 and 10,000 IU for women over 19.) For pregnant women: 2,500 IU for pregnant women under 18; 2,565 IU for pregnant women over 19. (Upper limit is 9,335 IU for ages 14 - 18 and 10,000 IU for women over 19. It should be noted that some experts recommend 8,000 IU as the upper limit during pregnancy.) Warning: Use of the topical acne medication tretinoin, a vitamin A derivative, during pregnancy can cause birth defects. For nursing women: 4,000 IU for nursing mothers under 18; 4,335 IU for nursing mothers over 19. (Upper limit is 9,335 IU for ages 14 - 18 and 10,000 IU for women over 19.) For men: 3,000 IU ages 14 - 18; 3,000 IU for ages 19 and above. (Upper limit is 10,000 IU.) Note: In determining the daily vitamin A allowance, experts also take note of provitamins, such beta carotene, that convert to vitamin A. Some experts recommend 3 - 6 mg of beta-carotene. Vitamin A is also now being measured with a new unit called the Retinol Activity Equivalent (RAE or RE). One RE is equal to 1 mcg. Retinol is the most active form of vitamin A and it is also converted in the liver from carotenoids. One RE is equal to 12 mcg of beta-carotene or 24 mcg of alpha-carotene or beta-cryptoxanthin).
Foods containing the vitamin	Animal products, such as liver, dairy products, eggs, and fish liver oil. Provitamin A carotenoids are also found in dark red, green, and yellow vegetables and fruits. Requires some dietary fat to be absorbed.
Effects of deficiencies	Skin disorders, severe diarrhea, and eye damage. In less developed countries severe deficiencies cause blindness in 250,000 children each year. Diets low in vitamin A may also increase the risk of developing cancer. Low dietary intake of vitamin A has been associated with impaired lung function in children.
People at risk for deficiencies	Preschool children and any child with inadequate intake of protein, calories, and zinc. Iron deficiency may also impair metabolism of vitamin A. People with asthma. People with serious disorders in the intestine, liver or pancreas, such as cystic fibrosis, steatorrhea, biliary obstruction, inflammatory bowel disease, cirrhosis, and others. People who have undergone Roux-en-Y gastric bypass surgery. Vegans (vegetarians who do not eat eggs and dairy). Such individuals should be sure to have plenty of deep-colored fruits and vegetables. People who abuse alcohol. It should be noted, however, that people with alcoholism may be at risk for vitamin A deficiency, but a combination of high-dose vitamin A and alcohol may cause toxic effects in the liver. Healthy adults usually have a year's store of vitamin A in the liver, so temporary nutritional deficiencies or problems with fat absorption are unlikely to cause serious vitamin A deficiency problems.
Toxicities	Very toxic when taken in high-dose supplements for long periods of time. Symptoms of overdose include dizziness, nausea, vomiting, headache, skin damage, mental disturbances, and, in women, infrequent periods. Can affect almost every part of the body, including eyes, bones, blood, skin, central nervous system, liver, and genital and urinary tracts. Severe toxicity can cause blindness and may even be life threatening. In children, chronic overdose can cause fluid on the brain and as well as adult complications. High consumption of vitamin A may also increase the risk of gastric cancer and the risk of osteoporosis and fractures in both men and women. Pregnant women who take amounts not much higher than RDA levels increase the risk for birth defects in their children. Liver damage can occur in children who take RDA-approved adult levels over prolonged periods of time or in adults who take as little as five times the RDA-approved amount for 7 - 10 years.


	B Vitamins: General Information	Vitamin B1 (thiamin)
Benefits	The B vitamins have a wide and varied range of functions in the human body. Most B vitamins are involved in the process of converting blood sugar into energy.	Essential for converting blood sugar into energy and is involved in metabolic activities in nerves, heart, and muscles and in the production of red blood cells.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)		RDA is 1.2 mg per day for men and 1.1 mg for women.
Foods containing the vitamin		Best source is pork and good sources are dried fortified cereals, oatmeal, corn, nuts, cauliflower, and sunflower seeds. Supplements for people with normal diets and health are unnecessary.
Effects of deficiencies	Deficiencies are uncommon in the U.S., but when they occur, they usually involve several B vitamins, since many of them come from the same food groups.	Severe vitamin B1 deficiency is known as beriberi. It can cause visual disturbances, paralysis, staggering, loss of sensation in the legs and feet, psychosis, and congestive heart failure.
People at risk for deficiencies	Alcohol interferes with these vitamins, and some of the physical and mental problems that alcoholics experience may be attributed to a deficiency of B vitamins. Elderly people are also at risk for deficiencies because of inadequate diets and potential interference with B-vitamin absorption by medications. Deficiencies can occur in severely malnourished people or in those receiving long-term dialysis or intravenous feeding. Vegetarians may be at risk.	See general vitamin B description.
Toxicities	Because the B vitamins are water-soluble and eliminated in the urine, toxic reactions from oral administration of most of them are extremely rare. (Exceptions are niacin and B6.) It should be noted that substances known as B15 (pangamic acid) and B17 (laetrile) are neither vitamins nor nutrients; both chemicals are highly dangerous and have no proven nutritional or health value.	No toxic effects have been reported from thiamin.


	Vitamin B2 (riboflavin)	Vitamin B3 (niacin) also known as nicotinic acid	Vitamin B5 (Pantothenic Acid)
Benefits	Important in the production of energy.	Helps break down blood sugar for energy. Acts as a vasodilator, widening blood vessels and increasing blood flow. May be prescribed for improving cholesterol levels.	Important for metabolism of fats, carbohydrates, and proteins, as well as production of steroid hormones and other important chemicals.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	DRI is 1.7 mg.	DRI is 20 mg.	Adequate intake (AI) is 4 - 7 mg.
Foods containing the vitamin	Liver, dried fortified cereals, dairy products, fish. Some dark green vegetables. Supplements for people with normal diets and health are unnecessary.	Mackerel, swordfish, chicken, veal, dried fortified cereals, pork, salmon, and beef liver. Supplements are unnecessary in people with normal health and diets.	Whole grains, beans, milk, eggs, and liver. Supplements are unnecessary in people with normal health and diets.
Effects of deficiencies	Deficiencies affect the skin and mucous membranes and can cause cracks on the lips or corners of the mouth, eczema of the face and genitals, a burning sensation on the tongue, eye irritation. May contribute to anemia when iron levels are low and contribute to elevated levels of homocysteine, a heart risk factor.	Deficiency causes pellagra; symptoms can include eczema, intestinal and stomach distress, depression, headache, thinning of the hair, and excess saliva production.	Deficiency is unlikely except in company with other B vitamin deficiencies. Symptoms include abdominal distress, burning sensation in the heels, and sleep problems.
People at risk for deficiencies	See general vitamin B description.	Alcoholics and any malnourished persons.	Alcoholics and any malnourished persons.
Toxicities	Until recently, no toxic effects had been reported even from large doses of riboflavin. However, one study indicated that high consumption of vitamin B2 might increase the risk of stomach cancer. More research is needed. (In the same study, vitamins B1, B3, and B6 were protective.)	Even mildly high doses of niacin can cause hot flushing of the face and shoulders, headache, itchiness, and stomach problems. Some report heart disturbances and temporarily lowered blood pressure. Large doses may produce ulcers, gout, diabetes, and liver damage, which are usually reversed when high doses are discontinued.	Although no toxicity has been reported in humans, high dosages have caused liver damage in rats.


	Vitamin B6 (pyridoxine)	Vitamin B12 (cobalamin)
Benefits	Has an effect on over 60 proteins in the body, importantly, those that play a role in the nervous system, in red and white blood cell production, and in heart disease.	Essential for the production of blood cells, manufacturing genetic material, and for healthy functioning of the nervous system. New evidence suggests that high levels of B12 may protect against colon and rectal cancer.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	RDA is 1.3 mg in adults under 50 and 1.7 mg for older men and 1.5 for older women. (Some experts recommend 3 to 6 mg for people who need heart protection.) Upper limit is 100 mg for adults.	RDA is 2.4 mcg in men and nonpregnant women, 2.6 mcg in pregnant women, and 2.8 mcg in nursing mothers.
Foods containing the vitamin	Meats, oily fish, poultry, whole grains, dried fortified cereals, soybeans, avocados, baked potatoes with skins, watermelon, plantains, bananas, peanuts, and brewer's yeast.	The only natural dietary sources are animal products, including meats, dairy products, eggs, and fish (clams and oily fish are very high in B12). Like other B vitamins, however, B12 is added to commercial dried cereals.
Effects of deficiencies	Increased levels of homocysteine, associated with heart disease and possibly Alzheimer's disease. Skin problems and nervous system disorders, including impaired memory and concentration. Increased risk for kidney stones. One study found a correlation between vitamin B6 deficiency and inability to conceive or carry a child to term. In unborn children, some evidence shows that lack of vitamin B6, in addition to vitamin B12 and folic acid, may be responsible for defects such as cleft lip and palate and spina bifida. Supplementation with these vitamins is advised during pregnancy. Note: People who have been taking more than 50 mg for some time and stop suddenly are at risk for a so-called rebound deficiency. When people stop, they should taper off slowly.	Deficiencies elevate homocysteine, a possible risk factor for heart disease and Alzheimer's disease. Increased risk of bone fractures. Abnormal gaits in the elderly. May cause severe depression, memory loss, instability, disorientation, and decreased reflexes, and possibly hearing loss. Children who are deficient may experience growth failure. Deficiencies in pregnant and breast-feeding women may cause neurologic harm in their offspring. A genetic defect that causes vitamin B12 deficiencies is responsible for pernicious anemia, a serious disorder that causes rapid heart rate, shortness of breath, dizziness, weakness, and fatigue. It must be treated with injections of vitamin B12 or else neurologic damage may occur.
People at risk for deficiencies	Alcoholics and any malnourished person. In rare cases, infants are born unable to metabolize pyridoxine; in such cases, seizures or convulsions can occur and vitamin B6 must be administered.	Alcoholics and any malnourished persons. Evidence suggests deficiencies may be caused by Helicobacter pylori (H. pylori) bacteria (a cause of ulcers). Nearly 30% of patients with inflammatory bowel disease have vitamin B6 deficiency, as well as low levels of iron and vitamin D. People who take the antibiotic isoniazid, high blood pressure medication hydralazine, and the drug penicillimine are at risk for vitamin B6 deficiency. The elderly and people with Crohn’s disease and those who have undergone ileal and ileocolonic resection may have trouble absorbing natural vitamin B12 and require supplements. Some evidence shows that patients with Parkinson’s disease treated with levodopa plus dopa decarboxylase inhibitor (DDC-i) and catechol-O-methyltransferase inhibitor (COMT-i) have low levels of both vitamin B12 and folate. As a result, they need to take supplements of these vitamins. Other studies have found that patients with diabetes treated with metformin, but not roziglitazone, are at risk for low levels of vitamin B12. Vitamin B12 deficiency is also common in patients with polyneuropathy. In up to one-third of patients, vitamin B12 deficiency is the sole or major contributing cause of their neuropathy. Treatment with vitamin B12 has a high success rate in improving the symptoms. Vegetarians are at higher risk for deficiencies.
Toxicities	Very high doses can cause nerve damage with symptoms of instability and numbness in the feet and hands, which may be permanent in some cases. Of specific concern are possible adverse effects on nerve development in the offspring of pregnant women who take large doses, such as for morning sickness.	There is no evidence of toxicity with this vitamin.


	Biotin (a B vitamin)	Choline (a B vitamin)	Folate, or Folic Acid, its synthetic form (a B vitamin)
Benefits	Involved in the production of amino acid proteins and fatty acids.	Essential for fetal brain development and for learning and memory.	Important for many metabolic processes in the body. It is used in the manufacturing of neurotransmitters (chemical messengers in the brain), in protecting the heart, and for synthesizing genetic materials (DNA) in the cells. It may improve blood flow.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	There is no DRI for biotin; some experts suggest 30-100 mcg.	RDA 425 mg for nonpregnant women, 450 mg for pregnant women, and 550 mg for nursing women.	Supplements may be folate (natural) or folic acid (synthetic). Folic acid is nearly twice as potent as folate. DRI is 400 mcg (.4 mg) of folate for the general population, 600 mcg during pregnancy and 500 mcg while nursing. Women who are planning to be pregnant should certainly take 400 mcg of folic acid before conception, during pregnancy, and while nursing.
Foods containing the vitamin	Dietary sources are eggs, milk, liver, mushrooms, bananas, tomatoes, whole grains, nuts, and brewer's yeast. Also produced by bacteria in the intestines.	Peanuts, eggs, cauliflower, and meats, especially liver.	Avocado, bananas, orange juice, cold cereal, asparagus, green leafy vegetables, dried beans and peas, and yeast. Folic acid supplements are now added to commercial breads and cereals.
Effects of deficiencies	Deficiencies are almost unheard of.	Low levels during pregnancy increase risk of birth defects in newborns.	As with vitamins B6 and B12, deficiencies of folate elevate levels of homocysteine, an amino acid in the body that may increase the risk for heart disease, and possibly Alzheimer's disease. Folic acid supplements lower homocysteine levels, but with little or no impact on risk of atherosclerotic disease in the heart or in the peripheral arteries and veins. This suggests that homocysteine may be a marker of cardiovascular disease, rather than a cause. This being said, one 2007 study found that folic acid supplementation in patients with low folic acids levels substantially reduced the risk of a first stroke. Low levels during pregnancy increase risk of birth defects in newborns, and folic acid supplementation plays a key role in preventing birth defects. Folic acid deficiencies Deficiencies can also cause depression and megaloblastic anemia and impair concentration, memory, and hearing.
People at risk for deficiencies			Alcoholics, malnourished persons, people with conditions that disturb the small intestine, people taking certain drugs, particularly methotrexate. Other risk factors for deficiency: high-dose aspirin, smoking, treatment for seizures, taking oral contraceptives.
Toxicities		Excessive doses can cause intestinal problems, and there is also some concern that high doses can be carcinogenic.	Possible connection between high consumption of folate/folic acid and colorectal cancer now under exploration. Some link between high doses and central nervous system disorders, zinc deficiency, and seizures in epileptics. This risk appears to be low, but results indicate that megadoses should be avoided. High amounts in the elderly may mask symptoms of vitamin B12 deficiencies.


Benefits	Vitamin C is a water-soluble vitamin. Acts as an antioxidant (reduces harm from damaging chemical processes in the body). Essential for the production of collagen, the basic protein in bones, cartilage, tendons, and ligaments. A 2007 study found that vitamin C supplements can help prevent the development of complex regional pain syndrome following wrist fracture. Another study found that prostate cancer risk dropped as consumption of vegetables high in vitamin C, such as broccoli and bell peppers, rose. It may also protect against brochoconstriction during exercise in people with asthma. May help boost the immune system.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	DRI is 75 mg (women) and 90 mg (men). (Smokers need an additional 35 mg.)
Foods containing the vitamin	Citrus fruits and juices, papayas, hot chili peppers, bell peppers, broccoli, potatoes, dark leafy greens, kale, red cabbage, cauliflower, cantaloupe, sweet potatoes, and Brussels sprouts. Orange juice is the most important source of vitamin C in the U.S., with frozen juice being the best source of the vitamin.
Effects of deficiencies	Scurvy is the primary deficiency disease. Affects most body tissues, particularly bones, teeth, and blood vessels. Early symptoms include tiredness, weakness, irritability, weight loss, and vague muscle aches. Later symptoms are bleeding gums, wounds that won't heal, rough skin, and wasting away of the muscles. Deficiencies may contribute to periodontal disease and gallstones. Low dietary intake of vitamin C has been associated with impaired lung function in children. Low intake may also increase lead levels in the blood.
People at risk for deficiencies	Deficiency has been uncommon in the U.S., usually occurring in the elderly, alcoholics, cancer patients, and some people on severely limited diets low in fresh fruits and vegetables. Surprisingly, however, studies now suggest that as many as 16% of middle-aged Americans, with the highest risk in smokers and middle aged men, are deficient in vitamin C. High doses of aspirin taken over a long period of time can interfere with vitamin C.
Toxicities	Tolerable upper limit is 2000 mg/day. High doses may cause headaches and diarrhea. Long-term high doses may increase risk for kidney stones. Ascorbic acid increases iron absorption so people with blood disorders, such as hemochromatosis, thalassemia, or sideroblastic anemia, should avoid high doses. Large doses may also thin blood and interfere with anticoagulant medications, blood tests used in diabetes, and stool tests. Rebound scurvy can occur after abrupt withdrawal from long-term large doses. This may affect infants or pregnant women who withdraw suddenly from high doses.


Benefits	Vitamin D is actually a single term for several hormones that are stored mainly in the liver and also in fat and muscle tissue. It is essential for the absorption of calcium into the bone and for normal bone growth.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	RDA is 200 IU (5 mcg) per day for children and most adults to age 50, 400 IU (10 mcg) for people between ages 50 and 60, and 600 IU over age 70. and 1000 IU (15 mcg) for those over 70. People who are housebound, do not have sufficient exposure to sunlight, or are dark-skinned individuals, as well as breast-fed infants, should take need vitamin D supplements. The maximum tolerated dose after the age of 12 months is 2,000 IU/day
How the body gets the vitamin	There are two forms of vitamin D. Vitamin D3 is made in the body from a chemical reaction to the ultraviolet radiation in sunlight. Vitamin D2 is found in a few food sources, including vitamin D fortified milk, fatty fish, egg yolk, and liver.
Effects of deficiencies	Softening of the bones caused by low levels of calcium and phosphorous (called rickets in children and osteomalacia in adults). Also increases the risk for bone-related knee problems, and hip fractures in postmenopausal women. Associated with a higher risk for prostate cancer and breast cancer risk. Evidence suggests that vitamin D deficiency may be responsible for poor muscle strength after bone fracture. The deficiency is associated with high blood pressure and diabetes, but it is unknown whether supplementation with vitamin D impacts these diseases. Studies now suggest vitamin D plays a role in age-related macular degeneration (AMD), and that drinking milk with added vitamin D can help protect against AMD.
People at risk for deficiencies	Older people, particularly if they live in the North, who are underexposed to sunlight. Obesity may also increase risk. There is some concern, in fact, that vitamin D deficiency may be a growing problem in the US among younger adults as sunscreen use becomes widespread. Individuals at highest risk for vitamin D deficiency are those who assiduously avoid the midday sun, wear protective clothing, regularly use sunscreen, and have dark skin. Exposure to sunlight for about 15 - 20 minutes at mid-morning or mid-afternoon three times a week is recommended for most people who live in temperate climates.
Toxicities	Vitamin D is very toxic in high doses. In infants, daily amounts higher than 1,000 IU can cause mental and growth retardation, kidney failure, and death. In children and adults, daily amounts over 50,000 IU can cause weakness, anorexia, vomiting, diarrhea, and mental changes. Prolonged use of megadoses can cause calcification of soft tissue and life-threatening kidney failure. Low-calcium diets and withdrawal from the vitamin can usually reverse the side effects except for kidney failure.


	Vitamin E (Tocopherol or Tocotrienol)	Vitamin K
Benefits	A fat-soluble antioxidant vitamin that helps prevent cell membrane damage and may inhibit oxidation of LDL cholesterol (a process that increases its harmful effects on arteries). Researchers once thought that vitamin E might protect against cardiovascular disease. This theory has been debunked. However, a 2007 study found that vitamin E supplementation reduced the risk of deep vein thrombosis (DVT) in women at risk for, or with a history of, DVT. Vitamin E supplements have also been shown to produce a statistically significant decrease in menopausal hot flashes. There is also early evidence that vitamin E may protect against ovarian cancer.	The most important function of vitamin K is its role in blood clotting and prevention of bleeding. As a result, the vitamin may be able to help treat hepatoma, leukemia, and hepatocellular carcinoma, a form of liver cancer. The vitamin also contributes to maintaining healthy bones and healing fractures. Vitamin K is widely used in Japan to treat osteoporosis, and studies suggest it may be effective in treating rheumatoid arthritis.
Recommended daily allowance (RDA) or dietary reference intake (DRI) (mcg = micrograms, mg = milligrams, IU = international units)	RDA is 15 mg (22 IU) for all adults, including pregnancy women. Nursing mothers need 19 mg (28 IU). (Supplements should be taken along with some oil or fat to be absorbed.) Vitamin E is composed of 8 compounds (four tocopherols and four tocotrienols). Vitamin E is most often available as supplements of dl alpha tocopherol (a synthetic form). Other vitamin E compounds may prove to be more active than the standard synthetic supplement. They include natural vitamin E, called d-alpha- or RRR-alpha-tocopherol succinate (VES). Other vitamin E compounds of interest are tocotrienol and beta and gamma tocopherol. Supplements that contain a combination of some of these forms may be most beneficial.	RDA is 60 - 65 micrograms (women) and 70 - 80 micrograms (men).
Foods containing the vitamin	Vegetable oils (particularly wheat germ oil), sweet potatoes, turnip greens, mangos, avocados, nuts, sunflower seeds, and soybeans. Tocotrienol (a possibly beneficial form) is found in natural tropical oils. Palm oil sold in the US is refined and does not contain tocotrienol.	Best dietary sources are canola oil, cruciferous vegetables, and soybean oil. Good sources are beef liver, bran, and olive oil. Also produced by bacteria in the intestines.
Effects of deficiencies	Deficiencies have not been established.	Easy bruising, bleeding. May increase the risk of hip fractures in women.
People at risk for deficiencies	Low-birth weight infants. People who eat a low-fat diet. People with medical problems that impair fat absorption, such as Crohn's disease, cystic fibrosis, steatorrhea, liver diseases (such as cirrhosis). People with abetalipoproteinemia, a rare genetic disorder that impairs fat metabolism.	Deficiency may occur in patients who have problems absorbing fats, such as those with cirrhosis, people who are on long-term antibiotic therapy, or who are taking other medications, including cholestyramine, Dilantin, and phenobarbital. Some evidence suggests that more young people may be deficient than previously believed.
Toxicities	Upper level recommended is 1,500 IU of alpha tocopherol. Large doses may cause bleeding problems, particularly in people taking anti-clotting medications. Some research now indicates that vitamin E, like other antioxidants, may have pro-oxidant and damaging effects. Although vitamin E is one of the best studied vitamins, research has yielded conflicting results, and definitive conclusions about the benefits and toxicity of vitamin E have not yet been determined. In a major 2005 study, there was no significant difference in cancer rates between people who took 400 IU of vitamin E daily and those who did not, although those who took the supplement had a higher risk of heart failure. Additional studies also link high levels of vitamin E with a slightly increased risk of heart failure and death. On the other hand, studies show that vitamin E may reduce heart problems in high-risk patients such as certain people with diabetes.	Allergic-type responses, including rash and itching, to high doses have been reported. Those who are taking Coumadin, an anticoagulant, should not take vitamin K without consulting a physician. Vitamin K deficiency can cause anorexia, lethargy, growth retardation, bone loss, soft tissue calcification, and death.

Carotenoids

Carotenoids are a group of more than 700 fat soluble nutrients that produce the colors in foods such as carrots, pumpkins, sweet potatoes, tomatoes, and other deep green, yellow, orange, and red fruits and vegetables. Many are proving to be very important for health. Beta carotene is the most widely studied carotenoid, but others are proving to be of great interest. As with some, but not all, carotenoids, beta carotene is known as a provitamin A because it converts to the vitamin in the body.

They are categorized as either xanthophylls or carotenes according to their chemical composition.

Carotenes are hydrocarbons and most are found in yellow, orange, and red vegetables. They include beta and alpha carotene and lycopene.

Beta Carotene and other Provitamin A Carotenoids. Beta carotene, alpha-carotene, and beta-cryptoxanthin are carotenes that are converted into vitamin A or retinol (the active form of vitamin A) in the body. They are found in many yellow fruits and vegetables. Beta carotene is the most widely studied carotenoid. Evidence now strongly suggests that when taken as a separate supplement it can have harmful effects.
Lycopene. Lycopene is responsible for the red color in fruits and vegetables, including tomatoes, red grapes, watermelon, and pink grapefruit. It is also found in papayas and apricots. It does not convert to vitamin A but may have important cancer fighting properties and other health benefits.
The beneficial actions of most carotenes such as those tomatoes, corn, and carrots, appear to be enhanced by cooking them, especially in oil (preferably olive, canola, or another monounsaturated oil). (Note: Cooking can also destroy certain nutrients, such as vitamin C, in these vegetables.)

Xanthophylls contain oxygen and most are found in green vegetables, such as broccoli, cabbage, and kale. They are also in yellow fruits and vegetables. Xanthophylls include lutein and zeaxanthin, which are both stored in the retina of the eye. Neither converts to vitamin A. Both are powerful antioxidants and may be very important for healthy eyes. Unlike carotenes, cooking may reduce the antioxidant activity of some xanthophylls in foods, although probably not to any significant degree.

Phytochemicals

The word phytochemicals means plant chemicals. Hundreds of phytochemicals are being studied. Many are believed to have a major positive impact on human health. Some contribute to the bright and vivid colors found in fruits and vegetables. The results of studies on specific phytochemicals are not necessarily applicable to the vegetables or fruits that harbor small concentrations of these chemicals.

Nevertheless, it is obvious that vegetables and fruits are healthful, which is probably due to some balance of phytochemicals, carotenoids, vitamins, fibers, and minerals rather than any single substance.

The benefits of individual phytochemical supplements are largely unproven. Furthermore, they are not regulated and high concentrations of some may behave like drugs and can be toxic and possibly even contribute to cancer cell growth.

Polyphenols are important phytochemicals, and flavonoids (or catechins) are members of the polyphenol family that may have significant health benefits. Laboratory studies have shown that specific flavonoids suppress tumor growth, interfere with sexual hormones, prevent blood clots, and have anti-inflammatory properties. In general, flavonoids are found in celery, cranberries, onions, kale, dark chocolate, broccoli, apples, cherries, berries, tea, red wine or purple grape juice, parsley, soybeans, tomatoes, eggplant, and thyme. Most common berries contain flavonoids and are particularly rich in potent antioxidants.

Among the important flavonoids are resveratrol, quercetin, and catechin. Evidence suggests that resveratrol (found in red wine, grapes, olive oil) may be extremely potent. In laboratory studies, it increases cell survival and has been shown to increase the life span of worms and fruit flies. Catechins are the primary flavonoids in tea and may be responsible for its possible beneficial effects. Flavonoids in dark chocolate may also be health protective.

Isoflavones, commonly known as phytoestrogens, have actions that are similar to the female hormone estrogen. A high consumption of soy, which is primarily composed of isoflavones, may reduce symptoms resulting from estrogen depletion during menopause. In a recent study, supplementation with isoflavones decreased hot flashes by 57% and night sweats by 43%, but other research is less favorable.

Lignan is another phytoestrogen and is found in the fiber layers of whole-grains, berries, some seeds, some vegetables, and a few fruits.

Isothiocyanates and related substances, indoles, are also known as mustard oils and are responsible for the sharp taste in cruciferous (also called brassica) vegetables. Such vegetables include broccoli, cabbage, Brussels sprouts, cauliflower, collards, kale, kohlrabi, mustard greens, rutabaga, turnips, and bok choy. Isothiocyanates also stimulate enzymes that convert estrogen to a more benign form and may block steroid hormones that promote breast and prostate cancers. (Cruciferous vegetables are also high in fiber, vitamin C, and selenium.)

Monoterpenes have two important phytochemicals, perillyl alcohol and limonene. They block proteins that stimulate cell growth and reproduction and are being tested for actions against cancer. Limonene is found in the peels of citrus fruits.

Organosulfurs are part of the allium family of phytochemicals. Compounds, such as allicin, may have benefits on the immune system, assist the liver in rendering carcinogens harmless, and reduce production of cholesterol in the liver. These compounds are found in garlic, leeks, onions, chives, scallions, and shallots.

Capsaicin seems to reduce levels of substance P, a compound that contributes to inflammation and the delivery of pain impulses from the central nervous system. Research suggests that it may inhibit cancer-generating substances. It is found in hot red peppers.

Sterols, which include sitosterol, stigmasterol, campesterol, and squalene, are found in vegetable oils. Sitosterol is the most studied and appears to have cholesterol-lowering effects.

Beta-sitosterols may help improve urine flow and urinary symptoms in men with enlarged prostate glands (benign prostatic hyperplasia, or BPH). A recent review study of five randomized trials (519 men) found that urinary flow and other urinary symptoms improved in men who took the herbal remedy from 4 - 26 weeks. The study’s authors cautioned that while beta-sitosterols show effectiveness in the short term, their long-term effectiveness, ability to prevent complications from BPH, and safety are not known. More research is necessary. Beta-sitosterols come from South African star grass, Hypoxis rooperi, or species of Pinus and Picea.

Healthy Foods

Evidence increasingly suggests that a varied diet, not individual food chemicals, is essential for basic health and a longer life. Such diets are rich in fresh fruits and vegetables and whole grains, and low in saturated fats.


Foods	Phytochemicals and Carotenoids	Vitamins and other valuable food components	Benefits
Apples	Flavonoids		May have activity against certain cancers (lung). Also may help maintain healthy cholesterol. May protect against asthma.
Beans	Flavonoids	Folate, iron, potassium, and zinc	Some experts believe beans are the perfect food.
Berries, all kinds of dark colored	Ellegic Acid	Vitamin C, minerals	The anthocyanins in berries such as bilberries, blueberries, cranberries, elderberries, and others, have numerous healthful properties including anti-cancer and antioxidant effects. Bilberry (Vaccinium myrtillis) is widely used to prevent macular degeneration. Blueberries may protect the aging brain. (In one study blueberries were most effective.)
Broccoli (also kale, Brussels sprouts, cauliflower)	Flavonoids, isothiocyanates, lutein, beta and alpha carotene. Note: Young sprouts of broccoli and cauliflower contain much higher levels of isothiocyanates than their mature forms.	Vitamin C, folate, fiber, and selenium	Anticancer properties. Protective against heart disease and stroke.
Carrots and other bright yellow vegetables	Lutein, beta carotene and other provitamin A carotenoids	Vitamin A (converted from carotenoids), vitamin C	Protects eyes, lungs. (Cooking carrots may increase the potency of food nutrients.)
Chocolate, dark. Note: Milk chocolate does not have benefits.	Flavonoids		Heart protective (may improve lipids and help prevent blood clotting. May have protective properties against lung cancer (not other cancers).
Eggs	Lutein	Many B vitamins, vitamin A, vitamin D	Although egg yolks are high in cholesterol, very little of it has a negative effect on people with normal levels. And the health benefits of eggs are now known to be very high. (People with diabetes or those with high cholesterol should restrict eggs, however.)
Fish, oily (mackerel, salmon, sardines)		Vitamin B3, B12. Essential fatty acids, selenium	Heart and brain protective.
Garlic	Allium (organosulfurs)		Possibly protective against certain cancers, heart diseases, and infection. Heating garlic can reduce benefits. Allowing crushed fresh garlic to stand 10 minutes before heating, however, may preserve beneficial chemicals while cooking.
Ginger	Zingiberaceae		Cancer fighting properties.
Grains (whole)	Lignans (phytoestrogens)	Vitamin B, Selenium (important antioxidant mineral), fiber, folate	May help reduce the ability of cancer cells to invade health tissue.
Grapes, including purple grape juice, and red wine	Flavonoids, (resveratrol, quercetin and catechin)		Fight heart disease and cancer. May help lower the risk for asthma.
Nuts		Vitamin E, vitamin B1, essential fatty acids, folate	Protects the heart and may help prevent stroke.
Onions	Flavonoids, allium (organosulfurs)		May have activity against certain cancers (lung).
Oranges	Monoterpenes	Vitamin C, folate, potassium.	Many health benefits. Increases HDL levels.
Potatoes (Sweet)		Vitamin C, vitamin E, vitamin A	Many health benefits.
Soy. The best products are tofu, soy milk, or whole soy protein.	Isoflavones (phytoestrogens), flavonoids, phytosterol, phytate, saponins.		May have effects similar to estrogen, including maintaining bone and benefiting the heart in women. May also be protective against prostate cancer and possibly other cancers. More studies are needed. Effects on breast cancer are uncertain. (Note: Soy may have different effects in men than in women. Of some concern is one study reporting more mental decline in men who consume greater amounts of tofu.)
Spinach and other dark green leafy vegetables	Zeaxanthin, Beta carotene	Vitamin C, folate, vitamin A (converted from carotenoids)	Protects lungs and brain.
Tea (Both black and green tea are beneficial. Best results associated with green tea.)	Flavonoids (primarily catechins)		Cancer fighting properties, particularly in green tea, which may be especially beneficial for smokers. Both black and green tea may protect against heart disease and stroke, although studies are mixed. Tea drinking also may help with weight control and help prevent osteoporosis.
Tomatoes	Lycopene, Flavonoids	Vitamin C, biotin, minerals	Studies link to reductions in prostate and other cancers. Infection fighters.
Note on Organic versus Inorganic Products. There is some evidence that organic produce has higher levels of antioxidants and that some agricultural chemicals may destroy flavonoids. Nevertheless, organic produce is expensive, and fruits and vegetables, no matter how they are grown, are still filled with healthful nutrients.

Dietary Health Benefits

The benefits of any dietary factors are very difficult to prove, and, to date, there is little evidence that most dietary supplements protect against major diseases in otherwise healthy people with normal eating habits. An exception is lutein, which is known to reduce the risk of macular degeneration. However, a diet naturally high in vitamins and minerals can be the best defense against many diseases. Fresh fruits and vegetables and whole grains are the primary sources of vitamins, carotenoids, and vitamins, as well as of fiber and important minerals.

Description of Oxygen-Free Radicals (Oxidants). Currently, the most important benefit claimed for vitamins A, C, E, and many of the carotenoids and phytochemicals is their role as antioxidants, which are scavengers of particles known as oxygen-free radicals (also sometimes called oxidants). These chemically active particles are by-products of many of the body's normal chemical processes. Their numbers are increased by environmental assaults, such as smoking, chemicals, toxins, and stress. In higher levels, oxidants can be very harmful in the following way:

They can damage cell membranes and interact with genetic material, possibly contributing to the development of a number of disorders including cancer, heart disease, cataracts, and even the aging process itself.
Oxygen-free radicals can also enhance the dangerous properties of low-density lipoprotein (LDL) cholesterol, a major player in the development of atherosclerosis.

Description of Antioxidants and Warnings on High-Dose Supplements. Antioxidant vitamins (A, C, and E), carotenoids, and many phytochemicals can neutralize free radicals. Unfortunately, although it is clear that vitamins are required to prevent deficiency diseases, high doses of vitamin C, vitamin E, and beta carotene supplements may also have pro-oxidant effects, which can be harmful in patients with cancer. In these people, high doses of antioxidant vitamins may actually protect cancer cells just as they do healthy cells.

The strongest evidence on negative effects to date comes from studies reporting an increase in lung cancer and overall mortality rates among smokers who took beta carotene supplements. In determining reasons for this disturbing effect, one animal study suggested that beta carotene increased enzymes in the lungs that actually promote cancerous changes. One study also reported a higher risk for cancer in male smokers who took multivitamins plus A, C, or E.

Some evidence also indicates that high doses of vitamin C may speed up atherosclerosis, or hardening of the arteries. In one study, women with heart disease who took antioxidant vitamins had a higher risk for heart attack or death than those who didn't take one.

Another study also reported a higher incidence and greater severity of respiratory infections in older adults who took 200 mg of vitamin E daily. Some researchers speculate that certain immune factors generate oxidants to fight bacteria. This antioxidant vitamin, then, may block that action. Research published in 2005 suggests that those who take large amounts of vitamin E (1,500 IU/day) may slightly increase their risk for heart failure and death, but this evidence is not considered conclusive. Further study is necessary.

Vitamins and Heart Protection.

Antioxidant Vitamins A, C, and E. Deficiencies in vitamins A, C, E, and beta carotene have been linked to heart disease. All of these nutrients have antioxidant effects and other properties that should benefit the heart. A study in patients with heart failure has shown that vitamin C can work with dobutamine, a powerful intravenous medication, to strengthen the heart’s ability to contract following a heart attack. In fact, a 2005 study has found that taking high doses of vitamin E is associated with an increased risk of heart failure. In 2007, the Women’s Antioxidant Cardiovascular Study failed to find that vitamins C, E, and beta carotene could reduce the risk of heart attack, stroke, need for revascularization, or cardiovascular death in women. According to the U.S. Preventive Service Task Force, evidence is insufficient to confirm or refute the benefits of supplements of any of these vitamins in protecting against heart disease.
Folate and B12 Vitamins. Deficiencies in the B vitamins folate (known also as folic acid) and B12 have been associated with elevated blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. One study, reported lower failure rates after heart surgery in patients who took folic acid and vitamins B12 and B6. And a major 2002 study suggested that lowering homocysteine levels with folic acid would reduce the risk for heart disease by 16% and stroke by 24%. However, a 2007 trial in adults with stable coronary artery disease found that lowering homocysteine levels 33% with B vitamins and folic acid had no effect on arterial inflammation, meaning that lower levels were unlikely to offer protection against heart attack or stroke. More evidence is needed to determine whether homocysteine plays a causal role in cardiovascular disease and whether the B vitamins are protective. Folate improves blood flow through the arteries, which may be important for the heart, regardless of its effect on homocysteine. Although people with high levels of homocysteine are prone to damaging blood clots in their arteries and veins, a 2007 study found that lowering homocysteine with folic acid and other B vitamins does not reduce the incidence of blood clots in the peripheral veins (deep venous thrombosis).
Niacin. Niacin (vitamin B3) is used for lowering unhealthy cholesterol levels. Although vitamin B3 is available over the counter, it can have significant side effects. A physician should prescribe niacin in order to ensure its safety and effectiveness. [See In-Depth Report #23, Cholesterol.]

Carotenoids and Heart Protection. Studies have reported that a diet high in fruits and vegetables containing beta carotene, lycopene, and other carotenoids may reduce the risk of heart attack. A small Finish study found that a diet high in tomatoes reduced total cholesterol and LDL ("bad") cholesterol. Diets low in lycopene (particularly from tomatoes) were associated with a significantly higher risk of heart disease and stroke.

Atherosclerosis is a disease of the arteries in which fatty material is deposited in the vessel wall, resulting in narrowing and eventual impairment of blood flow. Severely restricted blood flow in the arteries to the heart muscle leads to symptoms such as chest pain. Atherosclerosis shows no symptoms until a complication occurs.

Phytochemicals and Heart Protection. Several phytochemicals are associated with heart protection.

Flavonoids. Certain flavonoids, found in both black and green tea, dark chocolate, onions, red wine or red grape juice, and apples, appear to be strongly heart protective. In one study, people who consumed the most flavonoids in foods had a 20% lower risk for heart disease than those with low consumption. Flavonoids may protect against damage done by cholesterol and help prevent blood clots. A number of studies have now reported heart protection from the flavonoid catechin, which is found in both black and green tea. The flavonoid resveratrol, which is found in grape skin, appears to be responsible for the well-known heart protective effects in red wine and purple grape juice.
Organosulfurs. Organosulfurs found in onions and garlic have been under investigation for possible beneficial effects on cholesterol levels. One study reported an association between taking garlic capsules and significantly lower cholesterol-build up in the arteries of older women but not in older men. In the study, daily garlic supplements dramatically reduced the build-up of newly formed plaque in the arteries, while having much less effect on older, harder plaque deposits. Garlic supplements for cardiovascular disease may be most beneficial when used during earlier years among men and later years among women.
Isoflavones. Soy protein is the most studied source of isoflavones (known as phytoestrogens, or plant estrogens). Not all studies are consistent, but the majority has shown an improvement in at least one of the cholesterol components in people who consumed at least 25 grams of soy protein. A 2007 meta-analysis of all soy protein studies performed from 1990 - 2006 found that soy protein significantly decreased total cholesterol and LDL cholesterol, but had no effect on HDL or triglycerides. The effect was particularly evident in people with hypercholesterolemia. A 2007 study found that 12 weeks of soy supplement lowered total cholesterol and LDL levels in both Caucasian and African-American postmenopausal women. Soy may also reduce other heart risk factors, at least in certain populations. For example, in one 2002 study, soy was beneficial for controlling blood sugar and lowering LDL in postmenopausal women with type 2 diabetes. In a 2007 study of overweight men and postmenopausal women, soy protein reduced blood pressure and arterial stiffness. In another study, soy protein was associated with lower systolic blood pressure in men. The best sources are soy products (tofu, soy milk) or whole soy protein. Powdered soy protein that contains at least 60 mg of isoflavones may provide similar benefits.
Sterols. The plant sterols, including sitosterol, are also proving to be potent cholesterol fighters by blocking the absorption of cholesterol in the intestine. Sitostanol, a derivative of sitosterol, is being used in new margarine products to lower cholesterol levels. Sterols and stanols are now found in breads, cereals, yogurt, and fruit juices.

A healthy diet rich in fruits and vegetables and low in salt and saturated fats may significantly lower the risk for a first stroke, perhaps by helping to protect against high blood pressure -- a major risk factor for stroke.

Vitamins and Stroke Protection. The effects of antioxidant vitamins and carotenoids on stroke, dementia, or both are being studied. Studies are conflicting, however. A 2007 study of 8,171 women with cardiovascular disease reported that vitamins C, E, and beta carotene offered no protection against heart attack and stroke.

The B vitamin folate (usually in the form of folic acid) may protect against stroke. However, exactly which people benefit from this therapy has yet to be determined. Studies have suggested that people who have higher blood levels of folate have a lower than average risk for stroke. Its primary benefit in this case appears to be to reduce levels of homocysteine, an amino acid that has been strongly linked to an increased risk of coronary artery disease, stroke, and Alzheimer's disease. A 2007 meta-analysis of 8 trials found that folate supplements decreased homocysteine 20% and lowered stroke risk 18%. Interestingly, lowering homocysteine with folic acid and B vitamins had no effect on heart attack, strokes, amputations, need for dialysis, or death in patients with chronic or end-stage kidney disease.

Carotenoids and Stroke Protection. Some, but not all, studies have reported a lower risk of stroke from carotenoids, including beta carotene and lycopene.

Many fresh fruits and vegetables contain chemicals that may fight many cancers, including lung, breast, colon, and prostate cancers. Examples of important cancer fighting foods include the following:

Cruciferous vegetables (such as cabbage, Brussels sprouts, and broccoli)
Tomatoes (which contain lycopene)
Carrots (which contain alpha carotene)

Some evidence suggests that antioxidants may enhance the anticancer effects of chemotherapy. In multiple studies, patients who maintained their antioxidant levels were better able to withstand the high stress caused by chemotherapy or radiation therapy compared to those with low antioxidant levels. Antioxidant nutrients that may help reduce the side effects of chemotherapy include vitamins E and C, beta carotene, genistein and daidzein (isoflavones found in soy), and quercetin (found in red wine an purple grape juice).

Any protective effects of vitamins or specific phytochemical against cancer, however, appear to depend on the cooperative effort among them. Individual supplements of any vitamin or food chemical have not as yet shown any benefits.

Additionally, certain supplements may actually encourage tumor growth, particularly when taken in large amounts. Two 2007 studies found a connection between folate supplements and colorectal cancer. In one study, which was designed to evaluate the benefits of folic acid in patients who had previous colorectal adenomas (precancerous polyps), the researchers instead found that folic acid was associated with a higher risk of having 3 or more adenomas and noncolorectal cancers. In another study, it was noted that the downward trend in colorectal cancer diagnoses abruptly started to rise in 1996 when mandatory folate enrichment of grains within the U.S. and Canada began. Rates continue to exceed pre-1996 levels. Additionally, a large 2007 National Cancer Institute/AARP study found an increased risk of advanced and fatal prostate cancer in men who took more than 7 multivitamins a week, but no association between multivitamin use and localized prostate cancer.

High consumption of cruciferous vegetables (at least once per week) was associated with lower risk of kidney cancer, and low consumption (less than once per month) of cruciferous vegetables was associated with higher risk of kidney cancer in a multinational 2007 European study. Cruciferous vegetables also appear to offer protection against head and neck cancer resulting from chemical toxins found in cigarettes and alcohol, for example.

Vitamins and Cancer Protection. Because many cancers are thought to be initiated by the effects of oxygen-free radicals on DNA, the antioxidants A, C, and E and beta carotene have been intensively studied. A major study found that men who took selenium for 6 or 7 years reduced their risk of prostate cancer by 52%. Nevertheless, most individual supplements have not been proven to protect against cancer, and high doses may be dangerous.

A 2007 review of the diets of men exposed to asbestos found a decreased risk of prostate cancer associated with increasing intakes of vitamin C-rich vegetables, but not fruits and vegetables high in vitamin A. The chemopreventive role of silymarin (Silybum marianum), found in milk thistle extract, has been extensively studied and has shown anticancer efficacy against various cancers, especially prostate and skin, by inhibiting UVB radiation.

A review of 13 cancer registries found 416,134 cases of skin cancer and 3,776,501 cases of non-skin cancer as a first cancer. Rates from cancer registries in sunny countries (such as Australia and Spain) and less sunny countries (such as Canada and Iceland) were compared. The researchers concluded that vitamin D production in the skin decreases the risk of several solid cancers, especially stomach, colorectal, liver and gallbladder, pancreas, lung, female breast, prostate, bladder, and kidney cancers. The apparently protective effect of sun exposure against second primary cancer is more pronounced after non-melanoma skin cancers than melanoma.

Consumption of aflatoxins, a common fungus-related toxin infecting cereal grains, oil seeds, spices, tree nuts, and the milk of animals fed contaminated feed, is known to cause hepatocellular carcinoma, a deadly form of liver cancer. Rodent studies have shown that phenolic antioxidants, dithiolethiones, isothiocyanates, and triterpenoids may act as chemopreventive agents, dispersing aflatoxins and protecting against hepatocellular carcinoma. Human trials are planned. A similar study found that several isothiocyanates, diallyl sulfide, and polyphenolic compounds can prevent esophageal dysplasia from progressing to squamous cell carcinoma.

A review of all articles on vitamins and cancer published through February 2007 found that multivitamin/mineral supplement use may prevent cancer in individuals with poor or suboptimal nutritional status. One trial on poorly nourished Chinese showed supplementation with combined Beta-carotene, vitamin E and selenium reduced gastric cancer incidence and mortality, and overall cancer mortality. In a French trial, combined vitamin C, vitamin E, beta-carotene, selenium, and zinc reduced cancer risk in men but not in women. With few exceptions, neither beta-carotene nor vitamin E had benefits for preventing cancer. Beta-carotene supplementation increased lung cancer risk in smokers and persons exposed to asbestos.

A 2007 study of nearly 82,000 men and women in Sweden found that high intake of methionine was associated with reduced risk of pancreatic cancer. The same relationship was not seen with vitamin B6 or folate.

Vitamin A, C, and E. Although some studies have reported an association between low blood levels of these antioxidant vitamins and a higher risk for cancer, supplements of vitamins A, C, and E appear to have few advantages in most cases. And there are some studies finding higher cancer risks with high intakes of antioxidants. For example, a 2003 study reported a higher risk in melanoma in people with vitamin-C rich diets. Another study also reported a higher risk for cancer in male smokers who took multivitamins plus A, C, or E. (Vitamin E may be protective against bladder cancer and ovarian cancer.)
Vitamin D. Some studies have suggested that certain vitamin D compounds may inhibit certain cancer cells, specifically prostate cancer, from proliferating. More research is needed. In 2007, the National Cancer Institute confirmed that ultraviolet (UV) radiation exposure may reduce the risk of developing non-Hodgkin lymphoma (NHL), but only in patients with certain variations in the D vitamin receptor gene. A second 2007 study found that variations in this gene increase the risk of diffuse large B-cell lymphoma. A 2007 prospective analysis of 31,500 women in the Women’s Health Study evaluated calcium and vitamin D intake. The researchers found a moderately lower risk of premenopausal, but not postmenopausal, breast cancer with higher intakes of total calcium and vitamin D. A 2007 review of breast cancer cases reported in Ontario, Canada, found reduced breast cancer risks were associated with increasing sun exposure in women ages 10 - 19, less evidence for associations in women ages 20 - 29, and no evidence for ages 45 - 54. Researchers concluded that sun exposure earlier in life, particularly during breast development, may be key in the connection between vitamin D exposure and breast cancer risk.
Folic acid and B12. These B vitamins convert the amino acid homocysteine to methionine, a substance that helps prevent cells from becoming malignant. Folic acid may provide some protection against cervical and colon cancer. One small study showed a reduction of lung cancer cells in smokers taking folic acid and vitamin B12, but the study was very small, of short duration, and other factors might have biased the results. Still another study reported that folic acid may reduce the risk for breast cancer among women who regularly drink alcohol. (In the study, folic acid had no other effect on breast cancer.)

In 2006, a study for the National Institutes of Health reviewed randomized trials evaluating the effectiveness and safety of multivitamin and mineral supplements in preventing cancer and chronic disease. The studies had mixed results, and some supplements reduced cancer rates in certain populations. However, the reviewers concluded that current evidence is not sufficient to determine whether multivitamin and mineral supplements may prevent cancer and chronic disease.

Carotenoids and Cancer Protection. A number of studies have reported that fruits and vegetables rich in carotenoids are associated with protection against many cancers. Lycopene, found in tomatoes, may have particular value in protection against prostate, colon, lung, and bladder cancer. A 2005 study found that in one out of four men with genetic variations that cause them to be more sensitive to oxidative stress, supplementation with selenium, vitamin E, and lycopene significantly reduces the risk of prostate cancer. Individual supplements, however, do not offer any advantage. In fact, evidence now strongly suggests that beta carotene supplements increase the risk for lung cancer in smokers and people exposed to asbestos

Phytochemicals and Cancer Protection. The following phytochemicals appear to have cancer-protecting properties.

Isothiocyanates. Isothiocyanates and sulforaphane, found in cruciferous vegetables, may block the effects of carcinogens and suppress tumor growth. In one study, for example, women with the highest consumption of cruciferous vegetables had a 24% lower risk of breast cancer than women with the lowest consumption.
Isoflavones. Isoflavones, found in soy beans and flax seed, behave like estrogen in some ways and not in others. Researchers are very interested, then, in their effects on hormone-related cancers, including breast and prostate cancers. Much research has focused on soy. In general, a number of Asian studies have reported an association between a higher intake of soy and a lower incidence of reproductive and breast cancers. The effects of phytoestrogens, however, in all women are far from settled. Some evidence suggests the genistein in soy may have properties that are protective against lung cancer. Nonfermented soy products (tofu, soy milk) also may protect against stomach cancer, while fermented soy products (miso, soy paste) appears to increase the risk.
Organosulfurs. The organosulfur compounds found in the onion and garlic family may have very potent properties in suppressing or blocking carcinogenic substances. A 2007 study found that synthetic organosulfur compounds act as selective inhibitors of growth in breast cancer cells. Studies indicate that people who regularly consume fresh or cooked garlic have about half the risk of developing stomach cancer and two thirds the risk of colorectal cancer as people who eat little or no garlic. One possible explanation for garlic's anti-cancer effect in the stomach is its antibacterial action against H. pylori, which can promote stomach cancer. Taking garlic supplements, however, did not offer these benefits.

It should be noted that studies on the health benefits of vitamins and minerals have some important limitations. Some are held to rigorous standards, while others are not. In most cases, the results of existing research are complex, as they can easily be complicated by factors such as diet, exercise, the presence of healthy or unhealthy lifestyle behaviors, environmental factors, and more.


Disease or Condition	Vitamins	Carotenoids, Phytochemicals, and Healthy Foods
Alzheimer's Disease	Vitamin E. Some reports, including a large 2002 population study, have suggested that vitamin E intake, from food or supplements, may protect against mental decline. (One study suggested that the vitamin protected only those who carried the apoE4 gene. No strong evidence to date has found any protection from antioxidant supplements.) Some studies performed since 2002 challenge this finding, while others agree with it. B Vitamins. Some studies suggest that deficiencies of the B vitamins B6, B12, and folate may be a risk factor for Alzheimer' diseases, possibly because deficiencies elevate homocysteine levels, which some research now associated with a higher risk for Alzheimer's disease. Of these, folates may offer the best protection. In 2007, researchers at Tufts-New England Medical Center reviewed all human studies on folate, vitamin B-6, vitamin B-12, and cognitive function in the elderly conducted between 1966 and November 2006. Six of 10 folate studies reported a significant association between low baseline blood folate concentrations and poor cognitive test performance; 4 of 9 folate studies found associations between low blood folate concentrations and increased prevalence of Alzheimer's disease. No association between vitamin B-6 and vitamin B-12 blood concentrations and cognitive-test performance or Alzheimer's disease was seen, and B-vitamin dietary intake was not associated with cognitive function. Although the majority of studies indicated that low blood folate concentrations predicted poorer cognitive function, data are not solid, due to variations in the way the studies were conducted and lack of agreement on what constitutes a low B-vitamin status.	According to several studies, eating plenty of darkly colored fruits and vegetables may slow brain aging. The estrogen-like properties in isoflavones are of interest in the study of Alzheimer's disease. Animal studies suggest that soy might be protective against AD, particularly in postmenopausal women. Of some concern, however, were one population and a few animal studies suggesting that soy intake may pose a risk for greater mental decline among older men. More research is needed to confirm the effects of soy on the aging brain and to determine if there are gender differences.
Infectious Disease	Studies are mixed whether vitamin supplements protect against upper respiratory infections. Large doses of vitamin C, for example, may help reduce the duration of a cold, but they do not appear to protect against one in the first place, even after exposure to a cold virus. Two studies in 2002 on multivitamins reported opposite results, with one finding fewer infections and one finding no difference. It is possible that vitamin C or multivitamin supplements may be helpful in specific people, such those who are vitamin deficient or have medical problems that impair their immune systems. A review of all studies on vitamin C and pneumonia prevention found only 1 placebo-controlled, randomized trial conducted in an English boarding school during World War II. The trial found a statistically significant (80% or greater) reduction in pneumonia incidence among boys consuming vitamin C. Two less-well-constructed trials arrived at the same conclusion. Therapeutic trials were even scarcer. Only one randomized, double-blind, placebo-controlled study of vitamin C for treatment of pneumonia was found. In this trial, elderly patients given vitamin C had lower mortality and respiratory symptom scores. However, the benefits were restricted to the sickest patients. One other trial of adults in the former Soviet Union found a dose-dependent reduction in the time to recover with two vitamin C doses. One 2007 study on vitamin D found that a single dose by mouth of this vitamin might prevent healthy individuals from activating the bacterium that causes tuberculosis in patients who harbor the infection. Studies on vitamin E specifically have been mixed. A 2002 study, in fact, reported a higher incidence and greater severity of respiratory infections in older adults who took 200 mg of vitamin E daily. However, a 2004 clinical trial conducted among elderly nursing home residents found that daily supplementation with 200 IU of vitamin E did provide protection from upper respiratory infections, especially the common cold. At present, there is not enough evidence to recommend vitamin E for infection prevention. Diarrhea is a worldwide problem, particularly in developing countries and those with poor sanitation. Taking supplements with B-complex vitamins, vitamin C, vitamin E, and selenium may reduce the risk of diarrhea, depending upon the organism that causes the disease. Meanwhile, iron supplements appear to increase the risk of infection from organisms that cause diarrhea. Vitamin A has not been shown to prevent diarrhea. Urinary tract infections (UTIs) may affect as many as 25% of pregnant women. A 2007 study found that women who took vitamin C (100 mg) for 3 months had significantly fewer UTIs than women who did not take vitamin C supplements. Rotavirus is a common cause of acute gastric pain in children under age 5. A 2007 study showed that the high amount of isoflavones found in soy-based infant formula can help prevent rotavirus infection.	Lycopene, found in tomatoes, appears to have properties that protect infection-fighting white blood cells. Saponins extracted from ginseng and allicin (found in garlic) have properties that boost the immune system. Both ginseng and garlic have long been traditionally used for their health benefits.
Asthma	Vitamin C from diet has been associated with lower risk for asthma. In one study, some people with exercise-induced asthma benefited from taking vitamin C one hour before strenuous physical activity. In a 2007 study, taking 1,500 mg supplements of vitamin C for 2 weeks helped prevent exercise-induced airway narrowing in patients with asthma.	Flavonoids found in apples and red wine may help lower the risk for asthma. Some evidence indicates that a low dietary intake of antioxidant nutrients could increase the risk for lung damage. Such nutrients should be obtained from fresh, deep green and yellow-orange fruits and vegetables. A 2007 study found low blood lycopene levels in people with asthma. Increasing lycopene- and vitamin A-rich foods may help raise lycopene levels.
Eye Disorder	Cataracts and Macular Degeneration. Oxygen-free radicals play a role in cataract formation and age related macular degeneration, the most common cause of irreversible blindness in the elderly. Bilberry (Vaccinium myrtillis), which contains powerful anthocyanins, is widely used to prevent macular degeneration. Low levels of vitamin C in the lens of the eye have been particularly strong predictors of cataracts. People with cataracts are frequently deficient in vitamin A, the carotenes, lutein, and zeaxanthin. Studies on protection against cataracts using antioxidant supplements have been mixed, including two identically conducted studies that reported opposite results. Vitamin C currently has the strongest evidence for protection, but even with this antioxidant studies are not consistent. A combination of zinc and antioxidants, including vitamin C and E, may slow the progression of macular degeneration. (Vitamin E alone does not appear to be protective.) Glaucoma. Although no evidence exists that antioxidants will prevent glaucoma, some studies reported an association between vitamin E and improved visual fields in patients with glaucoma.	Several studies report that the consumption of antioxidant-rich foods is associated with a decreased risk for cataracts. Carotenoids, especially lutein, lycopene, and zeaxanthin, are especially eye-protective and may help prevent cataracts and macular degeneration. The National Eye Institute in 2007 suggested that people with intermediate- or advanced macular degeneration in one eye may want to take a vitamin formula shown to reduce the risk of macular degeneration in the other eye by 25%. The formula contains vitamin C, vitamin E, beta-carotene, and zinc. They also suggest that a diet high in lutein and zeaxanthin may help reduce the risk of advanced age-related macular degeneration. Several studies report that the consumption of antioxidant-rich foods is associated with a decreased risk for cataracts. Carotenoids, especially lutein lycopene, and zeaxanthin are especially eye-protective and may help prevent cataracts and macular degeneration.
Skin Disorders and Wrinkles	Topical vitamin A (retinol) has been shown to improve fine wrinkles due to aging, by increasing glycosaminoglycan, which retains water, and increasing collagen production. One small study found that taking a combination of vitamins oral C and E supplements may help reduce sunburn reactions, although the protection is much less than from sunscreens. Taking the vitamins singly did not have any effect. In fact, a 2002 study reported that oral vitamin C had no effect on sunburn reaction. Of concern, in the same study some natural antioxidants in the body were reduced in people who took the vitamin. Also of concern are studies reporting no benefits and possibly harm from topical vitamin C in the form of ascorbyl palmitate, which is soluble in fat. One study reported that older adults had fewer wrinkles if they ate whole grains, fresh fruits and vegetables, and the use of healthy oils (such as olive oil). Diet played a role in improving skin regardless of whether the people in the study smoked or lived in sunny countries.	The following foods and phytochemicals may be especially skin protective: Both green tea and ginger appear to have properties that may provide some protection against skin cancer. Green tea skin care products are now available. The substance silymarin, found in the milk thistle family (which includes artichokes), may inhibit UVB-promoted cancers in animals. In one interesting study, eating garlic protected animals very effectively against UVB damage by interfering with urocanic acid in the skin. Whether these results may apply to humans (and what quantities of garlic might be beneficial) is still unknown.
Osteoporosis	Vitamin D. Vitamin D is the essential companion to calcium in maintaining strong bones. Supplements may be needed for people who have poor exposure to sunlight. It should be noted that diet supplies most people's need and high amounts of vitamin D can be toxic. Of interest: Taking vitamin D supplements does not prevent bone loss in post-menopausal African American women, according to research published in 2005. Further study will be needed to determine whether vitamin D prevents bone loss in women from other ethnic groups. Vitamin K. Studies suggest that vitamin K has properties that protect bone and prevent fracture. Vitamin K2 (menatetrenone), a form of vitamin K, is proving to prevent fractures in people with osteoporosis. Vitamin K affects blood clotting, and supplements are not recommended without specific physician instruction. Vitamin B12. One study reported that in people with osteoporosis and pernicious anemia, taking vitamin B12 (which is used to treat the anemia) also increased bone density. Vitamin C and E. There has been some indication of a positive association between vitamin C and E intake and bone density, although evidence proving actual benefits is weak. Note on Vitamin A. High amounts of dietary vitamin A reduces bone density and may even increase the risk for fracture in both postmenopausal women and men. (A form of vitamin A, retinoic acid, has been found to stimulate bone break down.) Beta carotene does not appear to increase risk. Studies suggest that diets rich in fresh fruits and vegetables (which include those high in potassium and magnesium) reduce elimination of calcium from the body and help preserve bones.	Studies suggest that diets rich in fresh fruits and vegetables (which include those high in potassium and magnesium) reduce elimination of calcium from the body and help preserve bones. Studies are suggesting that isoflavones-rich soy products may actually improve bone density in postmenopausal women. A 2007 study of postmenopausal women in Italy found that 24 months of treatment with genistein plus calcium and vitamin D increased bone density, while women who took calcium and D alone lost bone density. Flavonoids and other compounds in tea may protect the bones.
Menstrual Disorders	Vitamin B6. Limited clinical evidence suggests that vitamin B6 may be beneficial in reducing premenstrual symptoms, including depression. Typically, women take 100 mg per day, although one study suggested that a lower dose (50 mg) may have the same effect. Other preliminary research indicates that women who receive the equivalent of 1,200 mg of calcium and 400 IU of vitamin D per day (through food or supplements) have a significantly lower incidence of premenstrual symptoms than women who did not. Vitamin B1. One study reported relief from menstrual pain using vitamin B1 (thiamin). Vitamin E. Several randomized controlled trials have shown that vitamin E significantly improves both physical and emotional premenstrual symptoms. One study reported that high doses of vitamin E helped reduce menstrual cramps. The doses were much higher than those recommended and could possibly increase the risk for bleeding. Although anecdotal evidence reports that vitamin E helps reduce the frequency of hot flashes for menopausal women, there is no clinical evidence to support this claim.

Resources

http://fnic.nal.usda.gov -- The Food and Nutrition Information Center
http://dietary-supplements.info.nih.gov -- Office of Dietary Supplements, National Institutes of Health
www.ars.usda.gov/ba/bhnrc/ndl -- Nutrient Data Laboratory
www.fda.gov -- Food and Drug Administration
www.eatright.org -- The American Dietetic Association
www.acsh.org -- American Council on Science and Health
www.aicr.org -- American Institute for Cancer Research
www.nutritiondata.com -- Information on vitamins and nutrients in foods
www.consumerlab.com -- Independent testing of nutritional supplements' contents and quality
www.usp.org -- US Pharmacopeia
www.herbs.org -- Herb Research Foundation

References

Age-Related Eye Disease Study Research Group, SanGiovanni JP, Chew EY, Clemons TE, Ferris FL 3rd, Gensler G, Lindblad AS, Milton RC, Seddon JM, Sperduto RD. The relationship of dietary carotenoid and vitamin A, E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22. Arch Ophthalmol. 2007;125(9):1225-1232.

Ambrosini GL, de Klerk NH, Fritschi L, Mackerras D, Musk B. Fruit, vegetable, vitamin A intakes, and prostate cancer risk. Prostate Cancer Prostatic Dis. 2007 May 22; [Epub ahead of print]

Aubertin-Leheudre M, Lord C, Khalil A, Dionne IJ. Six months of isoflavone supplement increases fat-free mass in obese-sarcopenic postmenopausal women: a randomized double-blind controlled trial. Eur J Clin Nutr. 2007 Feb 21; [Epub ahead of print]

Bermudez Y, Ahmadi S, Lowell NE, Kruk PA. Vitamin E suppresses telomerase activity in ovarian cancer cells. Cancer Detect Prev. 2007;31(2):119-28. Epub 2007 Feb 28.

Bodnar LM, Catov JM, Simhan HN, Holick MF, Powers RW, Roberts JM. Maternal vitamin d deficiency increases the risk of preeclampsia. J Clin Endocrinol Metab. 2007 ;92(9):3517-22. Epub 2007 May 29.

Clements RH, Katasani VG, Palepu R, Leeth RR, Leath TD, Roy BP, Vickers SM. Incidence of vitamin deficiency after laparoscopic Roux-en-Y gastric bypass in a university hospital setting. Am Surg. 2006;72(12):1196-202.

Coull DB, Tait RC, Anderson JH, McKee RF, Finlay IG. Vitamin B12 deficiency following restorative proctocolectomy. Colorectal Dis. 2007;9(6):562-566.

Dietary Guidelines for Americans 2005. Dept of Health and Human Services, US Dept of Agriculture. Accessed 10/3/2007.

Fischer Walker CL, Black RE. Micronutrients and diarrheal disease. Clin Infect Dis. 2007;45 Suppl 1:S73-S77.

Glynn RJ, Ridker PM, Goldhaber SZ, Zee RY, Buring JE. Effects of random allocation to vitamin E supplementation on the occurrence of venous thromboembolism: report from the Women's Health Study. Circulation. 2007;116(13):1497-503.

Headstrom PD, Rulyak SJ, Lee SD. Prevalence of and risk factors for vitamin B(12) deficiency in patients with Crohn's disease. Inflamm Bowel Dis. 2007 Sep 20; [Epub ahead of print]

Inderjeeth CA, Glennon D, Petta A, Soderstrom J, Boyatzis I, Tapper J.Vitamin D and muscle strength in patients with previous fractures. N Z Med J. 2007;120(1262):U2730.

Ishihara J, Otani T, Inoue M, Iwasaki M, Sasazuki S, Tsugane S; Japan Public Health Center-based Prospective Study Group. Low intake of vitamin B-6 is associated with increased risk of colorectal cancer in Japanese men. J Nutr. 2007;137(7):1808-1814.

J.G. Ray, C. Kearon, Q. Yi, P. Sheridan, and E. Lonn, for the Heart Outcomes Prevention Evaluation 2 (HOPE-2) Investigators. Randomized Trial of Homocysteine-Lowering Therapy and Risk for Venous Thromboembolism. Ann Intern Med. 2007;146(11):761-767.

Kitchin B, Morgan SL. Not just calcium and vitamin D: other nutritional considerations in osteoporosis. Curr Rheumatol Rep. 2007;9(1):85-92.

Kune G, Watson L. Colorectal cancer protective effects and the dietary micronutrients folate, methionine, vitamins B6, B12, C, E, selenium, and lycopene. Nutr Cancer. 2006;56(1):11-21.

Lim MR, Huang RC, Wu A, Girardi FP, Cammisa FP Jr. Evaluation of the elderly patient with an abnormal gait. J Am Acad Orthop Surg. 2007;15(2):107-117.

Martin H, Lindblad B, Norman M. Endothelial function in newborn infants is related to folate levels and birth weight. Pediatrics. 2007;119(6):1152-1158.

Mason JB, Dickstein A, Jacques PF, Haggarty P, Selhub J, Dallal G, Rosenberg IH. A temporal association between folic acid fortification and an increase in colorectal cancer rates may be illuminating important biological principles: a hypothesis. Cancer Epidemiol Biomarkers Prev. 2007;16(7):1325-1329.

Nardin RA, Amick AN, Raynor EM. Vitamin B(12) and methylmalonic acid levels in patients presenting with polyneuropathy. Muscle Nerve. 2007;36(4):532-535.

Ochoa-Brust GJ, Fernández AR, Villanueva-Ruiz GJ, Velasco R, Trujillo-Hernández B, Vásquez. Daily intake of 100 mg ascorbic acid as urinary tract infection prophylactic agent during pregnancy. Acta Obstet Gynecol Scand. 2007;86(7):783-787.

Parekh N, Chappell RJ, Millen AE, Albert DM, Mares JA. Association between vitamin D and age-related macular degeneration in the Third National Health and Nutrition Examination Survey, 1988 through 1994. Arch Ophthalmol. 2007;125(5):661-669.

Pham DQ, Plakogiannis R. Vitamin E supplementation in Alzheimer’s disease, Parkinson’s disease, tardive dyskinsia, and cataract: Part 2. Ann Pharmacother. 2005;39(12): 2065-2072.

Riccioni G, Bucciarelli T, Mancini B, Di Ilio C, Della Vecchia R, D'Orazio N. Plasma lycopene and antioxidant vitamins in asthma: the PLAVA study. J Asthma. 2007;44(6):429-432.

Ronnenberg AG, Venners SA, Xu X, Chen C, Wang L, Guang W, Huang A, Wang X. Preconception B-vitamin and homocysteine status, conception, and early pregnancy loss. Am J Epidemiol. 2007;166(3):304-12. Epub 2007 May 2.

Sahin M, Tutuncu NB, Ertugrul D, Tanaci N, Guvener ND. Effects of metformin or rosiglitazone on serum concentrations of homocysteine, folate, and vitamin B12 in patients with type 2 diabetes mellitus. J Diabetes Complications. 2007;21(2):118-123.

Tamori A, Habu D, Shiomi S, Kubo S, Nishiguchi S. Potential role of vitamin K(2) as a chemopreventive agent against hepatocellular carcinoma. Hepatol Res. 2007;37 Suppl 2:S303-307.

Tecklenburg SL, Mickleborough TD, Fly AD, Bai Y, Stager JMAscorbic acid supplementation attenuates exercise-induced bronchoconstriction in patients with asthma. Respir Med. 2007;101(:1770-1778.

Triantafyllou NI, Kararizou E, Angelopoulos E, Tsounis S, Boufidou F, Evangelopoulos ME, Nikolaou C, Vassilopoulos D. The influence of levodopa and the COMT inhibitor on serum vitamin B12 and folate levels in Parkinson's disease patients. Eur Neurol. 2007;58(2):96-99.

Vagianos K, Bector S, McConnell J, Bernstein CN. Nutrition assessment of patients with inflammatory bowel disease. J Parenter Enteral Nutr. 2007;31(4):311-319.

Velasquez MT, Bhathena SJ. Role of dietary soy protein in obesity. Int J Med Sci. 2007; 4(2):72-82.

Wang Y, Hodge AM, Wluka AE, English DR, Giles GG, O'sullivan R, Forbes A, Cicuttini FM. Effect of antioxidants on knee cartilage and bone in healthy, middle-aged subjects: a cross-sectional study. Arthritis Res Ther. 2007;9(4):R66 [Epub ahead of print]

Wang X, Qin X, Demirtas H, Li J, Mao G, Huo Y, Sun N, Liu L, Xu X. Efficacy of folic acid supplementation in stroke prevention: a meta-analysis. Lancet. 2007;369(9576):1876-1882.

Weingärtner J, Lotz K, Fanghänel J, Gedrange T, Bienengräber V, Proff P. Induction and Prevention of Cleft Lip, Alveolus and Palate and Neural Tube Defects with Special Consideration of B Vitamins and the Methylation Cycle. J Orofac Orthop. 2007; 68(4):266-277.

Wierzbicki AS. Homocysteine and cardiovascular disease: a review of the evidence. Diab Vasc Dis Res. 2007;4(2):143-50.

Zeisel SH. The fetal origins of memory: the role of dietary choline in optimal brain development. J Pediatr. 2006;149(5 Suppl):S131-136.

Ziaei S, Kazemnejad A, Zareai M. The Effect of Vitamin E on Hot Flashes in Menopausal Women. Gynecol Obstet Invest. 2007;64(4):204-207 [Epub ahead of print]

Zollinger PE, Tuinebreijer WE, Breederveld RS, Kreis RW. Can vitamin C prevent complex regional pain syndrome in patients with wrist fractures? A randomized, controlled, multicenter dose-response study. J Bone Joint Surg Am. 2007;89(7):1424-1431.

Review Date:
10/29/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com