Taking Vitamin D Supplements? Read This!

Anna Maltby, SELF

You can't turn around these days without hearing about the importance of vitamin D. Not only can deficiency lead to rickets and osteoporosis, but recent research is suggesting that vitamin D also could help protect you from certain types of cancer, diabetes and several other diseases.

It's hard to get D from food, and the other natural resource, the sun, isn't totally safe (sadly, using sunscreen -- which we recommend you ALWAYS do! -- can block the body's absorption of D).

So supplements seem like a natural solution. The problem, though, is that many vitamin D supplements don't contain the amount of D they say they do, and still others contain dangerous contaminants, a new report from ConsumerLab.com reveals.

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"We found problems with 29 percent of vitamin D-containing products," says Tod Cooperman, M.D., the president of ConsumerLab.com. "The most common problem was having less vitamin D than listed."

The problem there? Getting less D than you think you're getting (in one case in Cooperman's report, an adult supplement had less than one-third of the D it said it did!) means you're missing out on some of the benefits of the nutrient.

On the other end of the spectrum, one children's supplement contained a whopping 251 percent of the vitamin D it claimed to have!

"You can get too much of a good thing," Cooperman says. "Excessive intake of vitamin D as a supplement can potentially result in hypercalcemia (too much calcium in the blood), with symptoms including constipation, confusion, weakness, loss of appetite and painful calcium deposits."

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As for the products with contaminants -- brace yourself: It was lead.

"We found two products with lead contamination, possibly due to the calcium in the products," Cooperman says. "Adults can tolerate more lead than children, but it's still best to avoid unnecessary exposure."

Sadly, Cooperman says there's not much you can do to ensure that the label on the supplement you're taking is accurate. One pick that passed the test was GNC Vitamin D-3 1000 -- for more information and other supplement recommendations, visit ConsumerLab.com.

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