What is lactose intolerance?
Lactose intolerance is a problem that makes it hard to digest lactose. Lactose is a type of natural sugar found in milk and dairy products. This condition isn't the same thing as a food allergy to milk.
When lactose moves through the large intestine (colon) without being properly digested, it can cause gas, belly pain, bloating, and diarrhea. Some people who have lactose intolerance can't eat or drink any milk products. Others can eat or drink small amounts of milk products or certain types of milk products without problems.
What are the symptoms of lactose intolerance?
Symptoms of lactose intolerance can be mild to severe. Your symptoms may depend on how much lactase your body makes. Symptoms usually start 30 minutes to 2 hours after you eat or drink milk products.
Symptoms may include:
- Bloating.
- Pain or cramps.
- Gurgling or rumbling sounds in your belly.
- Gas.
- Loose stools or diarrhea.
- Throwing up.
How is lactose intolerance diagnosed?
A doctor can usually tell if you have lactose intolerance by asking questions about your symptoms. You may be asked to avoid dairy products for a short time to see if your symptoms improve. If symptoms improve, you may be asked to add small amounts of milk products to see if your symptoms return.
Sometimes doctors order tests to confirm the diagnosis. These simple tests check to see if you are digesting lactose normally.
- Hydrogen breath test. This is the most accurate lactose intolerance test. If the hydrogen levels in your breath are high, you may have lactose intolerance.
- Lactose tolerance test. This test measures your blood sugar after you eat or drink lactose. If your blood sugar levels don't rise, you may be lactose-intolerant. This test is not done for people who have diabetes.
These two tests usually aren't done for babies or very young children.
How is lactose intolerance treated?
There is no cure for lactose intolerance. But you can treat your symptoms by limiting or avoiding milk products, using milk with reduced lactose, or substituting soy milk and soy cheese for milk and milk products. You can also take dietary supplements called lactase products that help digest lactose.
How can you care for yourself when you have lactose intolerance?
If you have lactose intolerance:
- Limit the amount of milk and milk products in your diet.
- Eat or drink milk and milk products that have reduced lactose. Try milk with reduced lactose, such as Lactaid milk.
- Eat or drink other foods instead of milk and milk products. Try soy milk and soy cheese. And use nondairy creamers in your coffee.
- Use lactase products. These are dietary supplements that help you digest lactose.
- Try yogurt. Some people who are lactose-intolerant can eat some kinds of yogurt without problems, especially yogurt with live cultures.
- Read food labels for lactose and for lactose's "hidden" names. These include dry milk solids, whey, curds, milk by-products, and nonfat dry milk powder.
- Get enough calcium in your diet. Foods that have calcium include:
- Broccoli, bok choy, kale, collard greens, mustard greens, and turnip greens.
- Canned sardines.
- Calcium-fortified orange juice.
- Calcium-fortified soy milk and tofu.
- Almonds.
- Dried beans.
Lactose intolerance: When to call
Call your doctor now or seek immediate medical care if:
- You have new or worse belly pain.
Watch closely for changes in your health, and be sure to contact your doctor if:
- You do not get better as expected.
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