The New York Times warns us to suspect our supplements:
Using a test called DNA barcoding, a kind of genetic fingerprinting that has also been used to help uncover labeling fraud in the commercial seafood industry, Canadian researchers tested 44 bottles of popular supplements sold by 12 companies. They found that many were not what they claimed to be, and that pills labeled as popular herbs were often diluted — or replaced entirely — by cheap fillers like soybean, wheat and rice.
Supplement spokespeople state that the study's findings are "overblown," and that DNA barcoding often doesn't work on herbs that have been processed into pills. But the supplement industry's "safe until proven otherwise" gambit may hide bigger problems:
For instance, the study found that one product advertised as black cohosh — a North American plant and popular remedy for hot flashes and other menopause symptoms — actually contained a related Asian plant, Actaea asiatica, that can be toxic to humans.
I don't take herbal supplements because I am lazy and don't want to subject my body to any "Here's some gingko biloba to help recover the memories you lost after drinking that bottle of wine" cognitive dissonance, but apparently nearly half of Americans take some sort of multivitamin or supplement: do you? What are the good ones? Does this study concern you or is this just what we should expect from an unregulated industry?