Many Americans avoid dairy products, an important source of calcium, vitamin D and other nutrients, because they mistakenly think they're lactose intolerant, a panel of experts concluded Wednesday at a National Institutes of Health conference.
Solid estimates of the prevalence of lactose intolerance are lacking, because medical studies have different interpretations of the condition, the experts write in their concluding statement, which is published at consensus.nih.gov.
"I think that there are huge gaps in knowledge," panel chairman Frederick Suchy, a pediatric liver specialist at the Mount Sinai School of Medicine in New York, said at a news briefing after the 2 1/2-day conference in Bethesda, Md.
Lactose is the sugar found in human and cow milk. Only Northern Europeans and their descendants, with their history of raising cows and consuming dairy products, usually maintain their ability to digest lactose into adulthood, Suchy said.
In people from other parts of the world, levels of lactase, the enzyme that breaks down lactose, are genetically programmed to decline after weaning. Still, the experts wrote, most don't suffer the symptoms that characterize lactose intolerance, namely diarrhea, abdominal pain and gas.
If you have such symptoms, Suchy said, you should talk to your doctor, who can rule out more serious ailments, such as celiac disease. He noted that one simple way to check whether you have lactose intolerance is to avoid dairy products for a few days and see whether your symptoms go away.
Eliminating dairy products could be detrimental to your bones and, possibly, your heart, blood pressure and colon, Suchy said. And it's unnecessary, said panelist Marshall Wolf, a Harvard Medical School internist in Boston. He emphasized that lactose intolerance is not like a food allergy: "It's not something where a little bit of milk is going to make you very sick."
Yogurt and low-fat cheeses tend to have less lactose than other dairy products, Suchy said, and drinking small amounts of milk throughout the day or with meals may be better tolerated than guzzling a lot at one time.
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