The National Academies of Science, Engineering and Medicine recommends that most adults get about 600 international units of vitamin D per day through food or supplements, increasing that dose to 800 IUs per day for those 70 or older.
In addition to heart problems triggered by some supplements, emergencies often arise when kids swallow dietary supplements meant for adults, according to the CDC analysis, or when older adults choke on the pills.
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Even versions of Zi Xiu Tang Bee Pollen labeled "genuine" and "anti-counterfeit" have been found to contain the drug sibutramine, which was supposed to come off the U.S. market in 2010 for safety reasons.
Food and Drug Administration
Ads often tout dietary supplements and vitamins as "natural" remedies. But studies show megadoses of some vitamins can actually boost the risk of heart disease and cancer, warns Dr. Paul Offit.