Lactose intolerance occurs when your small intestine does not produce enough of an enzyme called lactase. Symptoms of lactose intolerance are flatulence, bloating, diarrhea, cramps and abdominal pain within two hours of consuming dairy products. Babies have lactase to help them to digest breast milk and cow's milk, but our bodies often stop producing lactase after infancy, causing lactose intolerance. The good news is that lactose intolerance is treatable with a lactose-controlled diet.
Types
There are two types of lactose intolerance: primary and secondary. Primary lactose intolerance is the most common and occurs when the intestines decrease the amount of lactase produced. Secondary lactose intolerance is usually temporary and is the result of injury to the intestines, such as through diarrhea, surgery or a digestive tract disease. It is important to know which kind of lactose intolerance you have before starting a lactose-controlled diet.
Statistics
Lactose intolerance is not a dangerous condition and is very common in adults. An estimated 30 million Americans are lactose intolerant to some degree by the age of 20. According to Dr. Daniel Swagerty, Jr., who published a report in American Family Physician called "Lactose Intolerance," in May 2002, up to 15 percent of people of northern European descent, up to 80 percent of African Americans and Latinos, and nearly all Asians and American Indians are lactose intolerant by adulthood.
Diet
A lactose-controlled diet is a diet that avoids all dairy products that contain lactose. You should permanently follow a lactose-controlled diet if you have primary intolerance. Secondary lactose intolerance usually requires only temporary dietary restrictions. Foods that have hidden lactose include baked goods, processed foods, salad dressings, candy, instant foods and and lunchmeat.
You should also avoid products that contain curds, whey, dry milk, nonfat dry milk and milk solids. Milk substitutes that you should be able to tolerate include non-dairy creamer, soy milk and almond milk. Many stores also carry lactose-free dairy products. Note that some dairy foods have more lactose than others do; you may be able to eat small amounts of buttermilk, yogurt, ice cream and cheese if you are lactose intolerant.
Supplements
If your doctor diagnoses you with a mild case of lactose intolerance, you may be able to eat dairy products if you take over-the-counter lactase enzyme supplements. The lactase enzyme supplements may not completely relieve your lactose intolerance symptoms either because they are not completely effective for you or because the dosage that you take is insufficient. Therefore, you should not think of the lactase enzyme supplements as a replacement for a lactose-controlled diet.
Malnutrition
If you need to go on a lactose-controlled diet to treat your lactose intolerance, you will need to eat other foods to replace the calcium, riboflavin, vitamin D and protein usually ingested from dairy products. Foods containing calcium include beans, bok choy, spinach, fortified cereal and tofu. Non-dairy foods rich in vitamin D include oysters, fortified cereal and fish. Meat, fish, eggs, poultry and soy are high in protein. Foods rich in riboflavin include proteins, leafy green vegetables, peas and fortified cereals.
References
- American Family Physician; "Lactose Intolerance"; Swagerty, Walling and Klein; 2002.
- Medline Plus: Lactose Intolerance
