Dr. M.J. Bazos, Patient Handout

LACTOSE INTOLERANCE


About Your Diagnosis

If you have difficulty digesting cow’s milk, you have lactose intolerance. Lactose is the main sugar in cow’s milk. This inability to digest lactose is caused by a shortage of the enzyme lactase. Lactase is normally made by the cells that line the small intestine. If these cells are damaged by injury or certain diseases, the production of lactase can be decreased or absent. In rare cases a child is born with the condition and is unable to produce lactase. The lactase breaks down milk sugar into simpler forms that can then be absorbed into the bloodstream. When there is not enough lactase to digest the amount of lactose consumed, you may have symptoms. Lactose intolerance is a common condition. Between 30 and 50 million Americans have the condition. It occurs more commonly as you age. It also occurs more commonly in certain racial and ethnic groups. As many as 90% of Asian Americans and 75% of African Americans and Native Americans are lactose intolerant. This condition is least common in individuals of Northern European descent. The condition is detected by tests used to measure the absorption of lactose from the digestive tract. These tests are the lactose tolerance test, the hydrogen breath test, and the stool acidity test. The stool acidity test should be used in children. All of these tests can be done as an outpatient. Rarely a small tissue sample (biopsy) may need to be taken
from the small bowel. This condition is not curable but the symptoms are controllable with diet modification and treatment.

Living With Your Diagnosis
Common symptoms of lactose intolerance usually begin 30 minutes to 2 hours after eating or drinking foods containing lactose. Symptoms include nausea, abdominal cramps, bloating, gas, and diarrhea. In children the symptoms are slightly different. Children tend to have foamy diarrhea and diaper rash and sometimes vomiting. Children also have slowed growth and development.

Treatment
Lactose intolerance is easy to treat. Infants and young children with lactose intolerance should not have foods containing lactose. Older children and adults generally do not have to avoid lactose products completely but should identify the amounts they can tolerate. If an older child or adult can only tolerate small amounts of lactose, lactase enzymes in drop and chewable forms are available over-thecounter. The drops can be put in milk before drinking. The chewable tablets are used to help individuals digest solid foods that contain lactose.

The DOs
• Read food labels carefully to avoid foods that may contain lactose.
• Talk to your physician or a dietitian about a proper balanced diet.
• Ensure adequate calcium intake through either diet or supplementation. Foods that are high in calcium include broccoli, kale, greens, oysters, and fish with soft bones (salmon and sardines).
• Yogurt and hard cheeses may be better tolerated and are high in calcium.
• Ensure adequate vitamin D intake to help with calcium metabolism. Exposure to sunlight will help with this. Eggs and liver are also good sources of vitamin D.
• If you have a family history of lactose intolerance, consider breast-feeding your baby.
• Infants with lactose intolerance should be given a soy-based formula.

The DON’Ts
• Avoid foods that may contain hidden lactose. These include bread and other baked goods, processed breakfast cereals, instant potatoes, soups, breakfast drinks, margarine, lunch meats (other than kosher), salad dressings, candies, and mixes for pancakes, biscuits, and cookies.
• Avoid prescription and over-the-counter medications that contain lactose as a base if you have severe lactose intolerance. Ask your pharmacist about specific medications.

When to Call Your Doctor
• If you or your child has symptoms of lactose intolerance.
• If a milk-free diet does not improve symptoms.
• If your child fails to gain weight.
• If your child refuses food or formula.

Websites:
www.niddk.nih.gov
nddic@aerie.com