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Lactose intolerance

  • Alternative Names

    Lactase deficiency; Milk intolerance; Disaccharidase deficiency; Dairy product intolerance


    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
    • Goat's milk (but drink it with meals, and make sure it is supplemented with essential amino acids and vitamins if you give it to children)
    • 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.

    Support Groups

    Expectations (prognosis)

    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.