Difficulty digesting milk and milk products is a symptom of lactose intolerance, a condition that produces uncomfortable gastrointestinal symptoms. Although the problem is common in adults, it can also occur in children, particularly those born prematurely. Limiting or eliminating milk in your diet can help prevent or control symptoms of lactose intolerance.
Milk and milk products contain lactose, a natural form of sugar. Lactase, an enzyme produced by the small intestine, helps your body digest lactose by breaking it down into simpler types of sugar. Lactose intolerance occurs when your body doesn't make enough lactase to completely digest the sugars, forcing the undigested lactose to remain in the intestinal tract. Although most people don't become lactose intolerant until the teen or adult years, the problem may actually start years earlier. The National Digestive Diseases Information Clearinghouse reports that the deficiency can begin to develop after age 2 when the body begins to produce less lactase. Lactose intolerance is a digestive problem that differs from a milk allergy, which is an immune system reaction to milk proteins.
When the undigested lactose lingers in the intestines, it causes several painful and uncomfortable symptoms, including cramps, bloating, gas, nausea and diarrhea. Everyone doesn't experience symptoms to the same extent, and you may find that your symptoms vary in intensity depending on the foods or beverages you eat or drink. Symptoms may begin as soon as 30 minutes after eating or drinking something containing milk or may not begin until two hours later.
You may be more likely to experience difficulty digesting milk and milk products if your parents have the same problem. Lactose intolerance affects higher number of people who are of Asian, American Indian, Hispanic or African descent. Lactase deficiencies can occur if the small intestine was injured, due to chemotherapy, severe diarrhea, Crohn's disease or celiac disease, although the problem is more common in infancy, according to the National Digestive Diseases Information Clearinghouse.
You may need to experiment with amounts of milk and milk products to decide how much lactose you can consume without experiencing symptoms. Combining milk and milk products with other foods may reduce severity of symptoms. The Cleveland Clinic recommends gradually adding small amounts of food and drink to determine your tolerance level. Carefully reading food labels can help you determine which foods contain milk or lactose. Lactose, milk or other milk products, including whey, milk byproducts, curds, milk solids and non-fat dry milk powder can be found as an ingredient in candy, potato chips, bread, cake mixes, protein bars and non-dairy creamers. If you find it hard to give up milk products, taking over-the-counter lactase pills before eating can allow you to enjoy milk with fewer symptoms.