Decreasing or removing milk products from the diet usually improves the symptoms.
Most people with low lactase levels can drink 2 - 4 ounces of milk at one time (up to one-half cup) without having symptoms. Larger (more than 8 oz.) servings may cause problems for people with lactase deficiency.
These milk products may be easier to digest:
Buttermilk and cheeses (they have less lactose than milk)
Fermented milk products, such as yogurt
Ice cream, milkshakes, and aged or hard cheeses
Lactose-free milk and milk products
Lactase-treated cow's milk for older children and adults
Soy formulas for infants younger than 2 years
Soy or rice milk for toddlers
You can add lactase enzymes to regular milk or take these enzymes in capsule or chewable tablet form.
Not having milk in the diet can lead to a shortage of calcium, vitamin D, riboflavin, and protein.
You may need to find new ways to get calcium into your diet (you need 1,200 - 1,500 mg of calcium each day):
Take calcium supplements
Eat foods that have more calcium (leafy greens, oysters, sardines, canned salmon, shrimp, and broccoli)
Drink orange juice that contains added calcium
Read food labels. Lactose is also found in some non-milk products -- including some beers.
Symptoms usually go away when you remove milk products or other lactose containing products from the diet.
Weight loss and malnutrition are possible complications.
Calling your health care provider
Call your health care provider if:
You have an infant younger than 2 or 3 years old who has symptoms of lactose intolerance.
Your child is growing slowly or not gaining weight.
You or your child has symptoms of lactose intolerance and you need information on food substitutes.
Your symptoms get worse or do not improve with treatment, or you develop new symptoms.
There is no known way to prevent lactose intolerance.
If you have the condition, avoiding or restricting the amount of milk products in your diet can reduce or prevent symptoms.
Genauer CH, Hammer HF. Maldigestion and malabsorption. In: Feldman M, Friedman LS, Sleisenger MH, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010: chap 101.
Lactose intolerance. The National Digestive Diseases Information Clearinghouse (NDDIC). NIH Publication No. 09-2751. June 2009.
A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, and David R. Eltz. Previously reviewed by David C. Dugdale, III, MD. Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California (7/7/2010).