Vitamin fans, take note: An editorial in the journal Annals of Internal Medicine suggests that multivitamins provide no health benefit in the long-run, and in fact, "should be avoided." The authors of the piece, "Enough is Enough: Stop Wasting Money on Vitamin and Mineral Supplements," summarize the work of three review studies in the same journal, which together find no effect for vitamins on cardiovascular health, cancer risk, cognitive health, or mortality. The bottom line, at least to the authors, is clear: We should stop wasting our money on multivitamins, since there’s little evidence to their benefit, and some evidence to their detriment. But as always, others say they jury is still out on this one.
It does go on to say, however, that this is in the context of trying to prevent chronic conditions and extend life. If you don't get enough of something your diet (e.g. many women have iron deficiencies, and people who eat a lot of junk food may lack all kinds of vitamins and minerals), then you should take supplements to make up the difference, but that's a completely different scenario from the person taking large doses of vitamins in order to try and prevent cancer, for example.
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