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Lactose Intolerance


What is lactose intolerance?

Lactose intolerance is when your body does not produce enough enzymes to properly digest lactose. Lactose is a sugar found in milk and other dairy foods. Lactose intolerance can lead to low levels of calcium if you do not eat or drink enough dairy foods.

What are the signs and symptoms of lactose intolerance?

Signs and symptoms usually depend on the amount of lactose you eat. You may have any of the following:

  • Abdominal bloating
  • Gas
  • Abdominal pain
  • Diarrhea
  • Nausea

How is lactose intolerance diagnosed?

Your healthcare provider will ask about your symptoms and when they occur. He may also ask about any medical conditions you have. Your healthcare provider will also examine you. You may need any of the following tests:

  • A hydrogen breath test measures the amount of hydrogen in your breath. You will be asked to drink a liquid with lactose. You will then breathe into a balloon-type container. High levels of hydrogen are usually present in your breath if your body is not digesting lactose properly.
  • A stool acidity test measures the amount of lactic acid and other fatty acids in your stool. These are substances that are produced from undigested lactose. The stool sample will then be sent to the lab for tests.

How is lactose intolerance managed?

  • Limit or avoid dairy foods. Your healthcare provider may recommend that you avoid dairy foods at first. Then, you can slowly introduce them back into your diet. You may find that you can eat small amounts of dairy foods at one time.
  • Eat and drink lactose-free or low-lactose foods. Try lactose-free, almond, rice, or soy milk. Infants with lactose intolerance may need to drink a lactose-free formula. Low-lactose foods include aged cheese (Swiss, cheddar, or parmesan), cream cheese, cottage cheese, or ricotta cheese. Read labels on all foods carefully because lactose is found in many foods. Ask your dietitian for more information about how to avoid or limit foods that contain lactose.
  • Avoid eating a dairy food by itself. You may be able to tolerate dairy foods better if you have them with other non-dairy foods. For example, have milk with cereal or cheese with crackers.
  • Ask your healthcare provider about enzyme supplements. You may be able to tolerate some dairy foods if you take an enzyme supplement (lactase tablet) right before you eat the dairy food.
  • Get enough calcium. If you eat very little or no dairy foods, you need to get calcium and vitamin D from other sources. Other foods that contain calcium include sardines, canned salmon, tofu, shellfish, dried beans, and almonds. Kale, spinach, broccoli, turnip greens, almonds, and calcium-fortified orange juice also contain calcium. Ask your healthcare provider if you need to take calcium supplements.

When should I contact my healthcare provider?

  • You continue to have symptoms, even after you make suggested changes.
  • You have questions or concerns about your condition or care.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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