Do You Need a Customized Multivitamin?

"Silver" multivitamin formulas for seniors have been around for decades, and other blends (e.g., women's, performance) have become increasingly popular. But the latest specialty supplements to hit markets are multivitamins made for people taking prescriptions, such as statins for high cholesterol and antidepressants, that can cause nutritional deficiencies. But are these customized multivitamins worth price tags roughly three times those of standard formulas?

There is some support for the idea of developing med-specific multivitamins. For example, studies suggest that up to 30 percent of people who take metformin, a common diabetes medication, have reduced absorption of vitamin B12. And science has documented that some people who suffer from depression have low blood levels of B vitamins, including folate.

Problem is, not everyone who takes a medication will experience the nutritional deficiencies sometimes associated with that drug. And for those who do, supplements aren't always the answer, says John Buse, M.D., Ph.D., president for medicine and science at the American Diabetes Association: "Perhaps the more reasonable thing to do is to work toward replacing less-nutritious foods with more nutritious ones." What's more, in cases where research suggests that supplementing a certain nutrient may be beneficial, the formulas being marketed aren't always the same as those tested, says James Lake, M.D., chair of the American Psychiatric Association's Caucus on Complementary, Alternative & Integrative Care. For example, a new multivitamin targeted at people taking antidepressants, such as Prozac, includes folic acid (along with vitamins B6, B12 and D); however, most clinical trials showing benefits of supplementing folate in people with depression use folinic acid (another form of the nutrient) by itself.

Talk with your doctor about all possible side effects, including nutritional deficiencies, of your prescriptions. He or she can help you decide if you should supplement any nutrients and, if so, the best way to do that.

And even if you're not taking any medications, you could be a candidate for needing to get more of certain nutrients—particularly vitamins D, folic acid, B12—through supplements. (Of course, you before taking any supplement you should always chat with your doctor.)

Vitamin D: We make vitamin D when UV rays hit our skin (sans sunblock)—but we often don't make enough of it. Older people, people with dark skin and people who live in areas where stretches without a sunny day are common (e.g., the Northeast) should supplement with a multivitamin/mineral or calcium with vitamin D supplement that supplies 400 IU (or up to 1,000 IU, say many experts). Choose one with the D3 form—or "cholecalciferol" in the ingredients list—as it's absorbed better than vitamin D2, or "ergosterol."

Folic acid: Women who might become pregnant need 400 mcg (100% DV) of folic acid, the supplemental form of the folate, a B vitamin necessary for the formation of healthy new cells. (This is in addition to consuming a diet containing plenty of folate-rich foods, such as beans and green vegetables.) Best source: a prenatal multivitamin/mineral.

Vitamin B12: Plentiful in meats, seafood, dairy and eggs, B12 isn't found in plant-based foods, so vegans should supplement. If you're over 50, the IOM recommends getting B12 in a supplement (a multivitamin/mineral works just fine): production of stomach acid, which you need to extract the vitamin from food, declines with age.

Read more on MSN Health & Fitness:

• Why Multivitamins Are Still a Good Idea
• Choosing a Vitamin and Mineral Supplement
• Dietary Supplements May Pose Risk to Older Cancer Survivors
• Vitamins, Family Style