“What you can buy in a bottle doesn’t come close to providing you with the wealth of benefits that come automatically when those nutrients are present in the form of food,” said Linda Van Horn, a research nutritionist at Northwestern University in Chicago. Nutrition advice, though, is never quite as simple as “take your vitamins” or even “don’t take your vitamins.” And further complicating matters, the answer isn’t the same for everybody. Much of the recent criticism of vitamins has revolved around megadoses, which can be 10, 20, even 30 times stronger than the amount recommended for the daily diet. But even multivitamins, which typically contain the recommended daily intake of a host of nutrients, are not universally accepted by nutritionists.
Alice Lichtenstein, a professor at Tufts University’s Friedman School of Nutrition, said there is no evidence that multivitamins are hazardous – but she said there’s also no compelling proof that they do much. Other experts believe multivitamins can help restore nutritional equilibrium to a defective diet. “If you look at what people eat, and there have been many national surveys to look at levels of nutrients and foods, there is a lot of deficiency,” said Dr. Meir Stampfer, a professor of epidemiology and nutrition at the Harvard School of Public Health. “We’re not talking about people with scurvy or rickets, but there are nutrients that large, substantial portions of the population are not getting,” he said, including vitamins B12 and D. And for some people whose extreme poverty keeps them from eating well, supplements can be lifesavers.