Some people shudder at the sight of drinking a whole glass of milk or a slice of pizza with extra cheese. It isn't the fat they're worried about, it's the lactose. People who are lactose intolerant no longer produce the enzyme lactase in their small intestine to break down the milk sugar lactose. Symptoms can include mild bloating, gas, or just an uncomfortable feeling in the belly 30 minutes to two hours after eating or drinking a dairy product. For some people, their reaction is more severe, and they end up with painful cramps, nausea, or diarrhea. How much and what types of dairy products are consumed can play a factor in how bad the reaction is.

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This video may joke around, but you wouldn't be laughing if you were lactose intolerant. So how do you know? To find out read more

If you notice that you have stomach issues whenever you eat foods that contain milk, well then it's probably safe to say that you're lactose intolerant. It can also run in families, so if your parents or siblings have a hard time digesting milk and cheese and such, then there's a good chance that you'll follow in their footsteps.

There are two tests you can take though, just to make sure.

Lactose Intolerance Test: You fast before the test and then drink a liquid that contains lactose. Several blood samples are taken over a two-hour period to measure your blood sugar levels. Normally, when a person eats a dairy product, the lactase enzyme breaks down the lactose into glucose and galactose, which raises the person's blood-sugar levels. If the lactase enzyme isn't there to do its job, then a blood sample would show no rise in the blood-sugar level, and the doctor would then confirm lactose intolerance.

Hydrogen Breath Test: You drink a liquid loaded with lactose, and your breath is analyzed. Normally the breath contains little hydrogen, but when there is undigested lactose in the colon, it's fermented by bacteria, which produces several gases including hydrogen. If your doctor sees raised levels of hydrogen in your breath, then you're lactose intolerant.

So now what? Unfortunately there is no cure for lactose intolerance, but there are two options. You can avoid all foods that contain milk or you can take lactase supplements (Lactaid pills). These allow you to pop a pill with your first bite of dairy, so you can enjoy the foods you love without the horrible symptoms.