A health fad that's hard to swallow

摘要

One in four people in the US regularly pops a magic pill in the hope it will improve their health, well-being and longevity. Different people swear by different ingredients, but there is one constant: the assumption that such pills, broadly known as dietary supplements, are safe. Most people assume that the vitamin A, B, C or D, or iron, selenium, manganese or cod liver oil, or ginseng, Ginkgo biloba or St John's wort they swallow has been rigorously tested by government and declared harmless. It has not. And evidence is mounting that many of these products contain ingredients that can kill, especially if taken alongside certain prescription drugs. Last week, the US Food and Drug Administration (FDA) received a report detailing the results of the first major investigation into how the dietary supplements market should be regulated. And the conclusions, from the Institute of Medicine (IoM), are stark.