Not All Dairy Is Taboo for Lactose Intolerant

Lactose, the sugar found in milk, is digested in the intestine by the enzyme lactase. People who lack this enzyme suffer from a condition called lactose intolerance.

In their bodies, milk sugar moves undigested into the colon, where it is fermented by bacteria. Within 15 minutes to two hours of consuming milk, this bacterial fermentation causes symptoms such as bloating, cramping, abdominal pain, gas, diarrhea and nausea.

Lactose intolerance, which tends to run in families, affects an estimated 75% to 80% of Asian, Native and African Americans and half of the country’s Latino population. A fifth of white Americans are also affected from birth. Intolerance to lactose can also be triggered by an intestinal disease or food poisoning.

Furthermore, levels of lactase tend to diminish naturally as we age. Although most infants produce enough lactase to digest breast milk, the levels begin to fall after weaning in those who are lactose intolerant.

Whether inherited or acquired, the condition is often thought of as an “all or nothing” problem for which the only cure is elimination of all dairy foods. In fact, most people produce at least some lactase, necessitating only partial removal of milk from the diet.

The American Dietetic Assn. says that four out of five people with even the lowest levels of lactase can drink a cup of milk a day without discomfort. Discovering how much can be tolerated is important because milk is a rich source of calcium, providing three-quarters of this mineral’s intake in the American food supply. Like phosphorous--also found in milk--calcium is crucial for building and maintaining strong bones.

To establish tolerance levels, start with small amounts of lactose-containing foods and gradually increase them until symptoms occur. Smaller, more frequent servings of lactose-rich foods are often easier to digest than larger single servings.

Surprisingly, although hard cheeses are made from milk, they contain little lactose, making them generally well-accepted. Yogurt is another exception. Made from fermented milk, scientists have discovered that the “friendly” bacteria in yogurt digests some of the lactose present.

The life of the lactose-intolerant person is also made easier by the virtually lactose-free and reduced-lactose brands of milks; lactase enzymes, available in drop or tablet form, that can be added to milk before drinking; and lactase supplements, taken before a lactose-rich meal.

Some foods, however, should be completely avoided; condensed and evaporated milks, for instance, contain twice the lactose of standard milk.

It is also a good idea to become a label sleuth. Because lactose provides good texture, binds water and acts as carrier for color, it is widely used in the food industry and is found added to many baked and processed foods. These can include anything from bread and cookies, cold cuts and hot dogs, salad dressings and sauces to drink mixes, dry cereals, ice cream and lasagna.

The key to coping with lactose intolerance is to remember that for most people it does not mean a life without milk. After some initial trial and error, it is a relatively straightforward food intolerance to manage successfully.

*

Amanda Ursell, a dietitian and nutritionist, is a London-based freelance journalist. Her column appears on the first Monday of the month. She can be reached at amanda@ursell.com.