Peter Barry isn't a doctor, a nutritionist or even an herbal healer, but customers constantly stroll into Baltimore's OK Natural Food Store seeking his advice on vitamins.
What's he got for hypertension? For energy? And the one everyone whispers: sexual enhancement?
A natural foods salesman for 22 years, Barry takes a few supplements of his own, but he thinks consumers are desperate for a magic pill. Standing before a giant wall of bottles bearing such labels as coral calcium, B-50 and Change-O-Life Blend, he offers his standard recommendation: "grandma's cooking."
"I see supplements as something we should work not to take," he said. "We should be concentrating on eating more local, seasonal, whole foods that provide the nutrients we need."
Nearly 40 percent of American adults regularly take a vitamin or mineral supplement, according to the Centers for Disease Control and Prevention, keeping the vitamin industry booming. U.S. sales of supplements totaled about $9.7 million in 2007 alone, according to the Nutrition Business Journal, which keeps tabs on the industry.
But while there is a dizzying variety of products on the market, evidence of their benefits remains murky. While many nutritionists have long promoted vitamins as nutrition's insurance policy, some doctors and researchers say not to bother even with the once-hailed one-a-day multivitamin.
"There's not enough evidence to tell people who are taking them to stop," said Mary Frances Picciano, Ph.D., a senior nutrition research scientist in the Office of Dietary Supplements at the National Institutes of Health. "And there isn't enough evidence to tell people who aren't taking them to start." Her agency concluded in 2006 that without more extensive clinical trials, there was little evidence to support the health benefits of multivitamins.
Still, many experts agree that certain vitamins benefit various groups. Calcium combined with vitamin D is often recommended for post-menopausal women to help prevent bone loss. It's recommended for older men, too. Extra iron can be helpful for women of childbearing age, who are at higher risk of iron deficiency than older people. And folic acid is universally recommended for women who may become pregnant to prevent birth defects.
There is sharp disagreement, though, about many other supplements, including such popular remedies as vitamins E and D.
