It's a good thing dietary guidelines aren't laws. If they were, just about all of us could be found guilty. Even if you load fruit onto your whole-grain cereal and pile greens on your sandwiches, chances are you're regularly falling short on one or more nutrients.
Many people take multivitamins to fill in these gaps, but since everyone's different, how do you pick the right pill? You can't buy a multivitamin with your name on it, but you can buy one aimed at your gender. Many multivitamins come in his and her varieties. Examples are One A Day Women's, One A Day Men's Health Formula, Centrum Ultra Women's and Centrum Ultra Men's. They're sold in grocery stores and drug stores everywhere. Expect to pay $10 or so for 100 tablets, enough for more than three months.
calcium (450 milligrams instead of 45 mg.) and iron (18 mg. instead of no iron at all). One A Day Men's Health Formula contains extra vitamins E (45 IU instead of 30 IU), C (90 mg. instead of 60 mg.) and B12 (18 mcg. instead of 6 mcg.). It doesn't have iron, but it has 600 mcg. of lycopene, an antioxidant found in tomatoes that is touted as a defense against prostate cancer.
FOR THE RECORD:
Multivitamins: An article in Monday's Health section about gender-specific multivitamins said Centrum Ultra Men's multivitamins contain no iron. They contain 8 milligrams of iron per tablet. —
Compared with the basic Centrum multivitamin, Centrum Ultra Women's contains extra vitamin D (800 IU versus 400 IU), calcium (500 mg versus 200 mg), and vitamin E (35 IU versus 30 IU). Both varieties contain 18 mg. of iron. Centrum Ultra Men's doesn't have iron but offers extra vitamin D (600 IU versus 400 IU) and vitamin E (45 IU versus 30 IU) along with 600 mcg. of lycopene.
Like almost all multivitamins, gender-specific varieties claim a long list of supposed benefits. The website for One A Day Women's says the product supports health of the bones, breasts, heart, reproductive system and skin. Centrum Ultra Women's promises to boost the immune system and provide more energy along with healthy skin, nails and hair. One A Day Men's Health Formula claims to support the prostate and heart. Centrum Ultra Men's supposedly enhances immunity and energy while supporting prostate, colon and heart health.
The bottom line
You probably shouldn't expect dramatic results from a multivitamin, says Jeffrey Blumberg, professor of nutrition science and policy at Tufts University in Boston. "It's not clear that multivitamins have some magical powers to prevent heart disease and cancer," he says. But they can bring most Americans more in line with nutritional guidelines, he adds, and since guidelines for women and men differ somewhat, a gender-specific multivitamin makes some sense.
In practice, though, the products on the market aren't necessarily in sync with guidelines. According to the Institute of Medicine, men and women have the same basic requirements for calcium and vitamins D, E and B12. (Women who are pregnant or nursing need extra amounts of many vitamins and minerals.) Men need a little more vitamin C than women (90 mg. each day versus 75 mg), and premenopausal women need more iron (18 mg. versus 8 mg.). For postmenopausal women, the iron quota is the same as for men.
At least one nutrient in the men's formulas may not help much. A 2007 study out of the National Cancer Institute and the Fred Hutchinson Cancer Research Center in Seattle found no evidence lycopene can lower prostate cancer risk.
Blumberg notes that there aren't any studies showing that gender-specific vitamins have any particular health benefits. Such studies would be very difficult and costly to run, he says.
In fact, the value of any multivitamin is an open question. A study of more than 160,000 women published in February concluded that there's "convincing evidence" that multivitamins don't protect postmenopausal women from common cancers or heart disease.
Still, it seems likely they have value to people who don't get enough nutrients in their diets -- which is pretty much everyone, says Victoria Drake, a Linus Pauling Institute research associate at Oregon State University in Corvallis.
Like Blumberg, Drake thinks gender-specific multivitamins make sense, especially because they offer different levels of iron. "That's the one you would worry about," she says. Women who are menstruating need relatively large amounts of iron to prevent anemia, but too much can encourage heart disease in men and postmenopausal women.
No multivitamin can exactly match a person's nutritional needs, Drake says. But one with the right amount of iron will probably be close enough.
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