Lactose intolerance (LI) is the body’s inability to digest lactose-containing foods, such as milk and milk-products. There are three types of lactose intolerance:
– Primary: It is experienced when the body decreases production of lactase with age.
– Secondary: It is experienced as a result of illness.
– Congenital: It is hereditary and very rare when a baby is born with lactose intolerance
This article will focus on primary lactose intolerance resulting from a decreased production of lactase. This decrease in lactase production appears to be genetically programmed. For example, although almost all Oriental people can not digest lactose, they may tolerate dairy products in childhood. However, they might begin to develop symptoms of lactose intolerance by 5 years of age. In genetically predisposed African American children, the intolerance develops by 10 years of age, and in Caucasian people by young adulthood.
Approximately 70% of the world’s population has primary lactase deficiency. The prevalence varies according to ethnicity, as well as the availability of dairy products in the diet. In populations with an abundance of milk products in the diet, especially among people of Northern Europe, the incidence of lactose intolerance may be as low as 2%, while nearly 100% of the Asian population, 80% of Native Americans, and 70% of Blacks are lactose intolerant.
Lactase is an enzyme produced in the small intestine and is responsible for the breakdown of lactose, the major milk sugar. As the undigested lactose passes from the small intestine into the colon, certain bacteria found there break down lactose and in the process produce gases, hydrogen and/or methane. These gases are absorbed by the bloodstream that carries them to the lungs. That’s why some people with lactose intolerance might have bad breath!
How is lactose intolerance managed?
Lactose intolerance is easily managed through dietary manipulation. Avoidance of foods with lactose will result in symptom resolution. To assure appropriate amount of calcium in the diet, it is crucial to include in the diet calcium-rich products, such as calcium-fortified lactose-free milk, soymilk, or calcium-fortified juices. Most lactose intolerant people can tolerate some lactose in their diet. Therefore, they should find out through trial and error the acceptable amount of dairy and include it in their diet. Studies show that dietary lactose enhances calcium absorption, and conversely, lactose-free diets result in lower calcium absorption. Thus, daily consumption of the tolerable amount of dairy is crucial to the optimal bone health.
Those who react to small amounts of lactose may try a lactase enzyme available over-the-counter. It is available in tablets and drops and is taken with the first bite of the lactose-rich food.
Hidden sources of lactose:
– Bread, pastries, and other baked goods
– Breakfast cereals
– Salad dressings
– Breakfast drinks
– Baking mixes
– Instant potatoes