Vitamins: Separating Fact From Fiction


There are enough myths around vitamins to make an ancient Greek blush, and it’s easy to see why.

We all know that vitamins and minerals are essential to good health — it says so right there on the cereal box. And we live in the more-is-better era of Hummers, Big Gulps, and McMansions. Which raises the obvious question: if taking 100% of the Recommended Dietary Allowance (RDA) of, say, dietary supplement shelves of a health food store or even your local supermarket. While many of the health claims are unproven or downright bogus, some supplements may be useful for some groups.

Major multivitamin makers typically produce different varieties for men, women, children and older folks. Picking a pill that fits your group makes sense, says dietitian Grotto, as the optimal level of various green tea or ginseng extract; the effect of these on weight control is yet unproven.

More dangerous are recommendations of vitamin megadoses to treat obesity, depression, carpal tunnel syndrome or other problems. At best, megadoses are a distraction from real treatments for these problems, experts say. At worst, they can cause injury or death.

So-called fat-soluble vitamins — that is, vitamins A, D, E, and K — accumulate in the body, making overdosing a real threat. Vitamin overdoses have been associated with problems, weakened bones, cancers, and premature mortality.

Until recently, water-soluble vitamins such as B and C were considered nontoxic, even at high doses. But now evidence is emerging that B-6 megadoses can cause serious nerve damage, Bailey tells WebMD.

Despite the warnings, the quest for a magic pill plunges ahead. Cross chuckles when patients show her weight loss supplements that claim wondrous effects “when taken in combination with a sensible diet and exercise.” Her response: Wouldn’t a sensible diet and exercise do the trick even without the supplement?