Why can some adults drink milk, yet others can’t? Blame it on your genes.
The bloating, nausea, pain, cramps, gurgling or rumbling, gas, loose stools or diarrhea, and throwing up usually begins 30 minutes to 2 hours after drinking milk or eating foods containing milk. It is estimated that 30 million to 50 million Americans over the age of 20 may experience these symptoms. If you do, you may be lactose intolerant.
Lactose is the main sugar found in milk. The enzyme lactase, produced in the cells of the small intestine, breaks down lactose into simpler sugars that can be absorbed by the body. When there is a deficiency of the enzyme, milk sugar passes into the large intestine without being properly digested. While not a dangerous condition, lactose intolerance can create severe discomfort and embarrassment for the individual.
Lactase, needed to digest the sugar in milk, is usually switched “off” or significantly diminished after weaning. In populations that have historically relied on dairy cattle for food, the gene stayed “on” and was passed on to offspring. Europeans and certain ethnic groups from East Africa rarely have trouble digesting milk sugar. Asians, American Indians, other Africans, Ashkenazi Jews, and Hispanics have a much higher prevalence of lactose intolerance.
Because most of us come from a mixed heritage, an individual’s degree of intolerance can vary from mildly irritating to debilitating. Medically this range of reaction can be divided into lactose maldigestion (more common) and lactose intolerance (less common).
There is no cure for the problem, but the symptoms can be resolved by limiting or, if needed, avoiding milk products. Start by trying smaller amounts of milk, a 1⁄2 cup, for example, drunk along with a meal. Chocolate milk and cooked milk – custard, pudding, and creamed soups – are often better tolerated. Most people with lactose intolerance can eat hard cheese, because the lactose is lost in the cheese making process. Softer cheeses like cottage cheese, ricotta, mozzarella, cream cheese, brie or camembert will have more lactose. You may not be able to eat these types or you may need to keep portions small. Processed cheese, like American, will have more lactose, as will ice cream and frozen yogurt.
In yogurt, the friendly live bacteria digest much of the lactose as the yogurt curd is formed. The same goes for buttermilk and kefir. Most lactose intolerant people can tolerate these with few problems.
Hidden sources of lactose include nondairy creamers, powdered artificial sweeteners, bread, cake, margarine, pancakes, waffles, breakfast cereals, salad dressings, and candies. Read the ingredient list carefully looking for milk, milk solids, sweetened condensed milk, nonfat dry milk, and cream. Lactose is also used as the base for many prescription and nonprescription drugs. For over-the-counter drugs check the ingredient list. For prescription drugs ask the pharmacist.
Today a number of brands of lactose-reduced and lactose-free milk, cheese and ice cream are available. Soy, rice, and almond-based milks are other lactose-free alternatives, as are soy cheese, ice cream, and yogurt. Lactase enzyme can be purchased in liquid form and added to milk. In 24-hours the added enzyme will reduce the lactose by over 70%. Taking chewable lactase tablets before a meal can also reduce symptoms. And, some people find they tolerate goat’s milk well.
The key to controlling symptoms is individuality. When you experience symptoms note the foods you ate in the last 2 hours. Eliminate them until symptoms subside and then add them back in smaller amounts. Over time most people get to know their bodies well enough to limit or avoid those foods that cause problems.