What’s the harm? Plenty:

Researchers found that the most common mistake users of herbal remedies make is believing that the substances they take actually work. An earlier National Institutes of Health study showed that about 19% of Americans take herbal supplements and more than half the time they’re using the substances to treat a specific health condition instead of just for general well-being. That’s fine, provided the supplements treat those conditions, but in more than two-thirds of cases, the preparations have never been clinically proved to be effective for those uses. And as any scientist will tell you, clinical proof–a randomized, controlled trial–is the gold standard for establishing a drug’s usefulness and safety. So a lot of dollars–not to mention medical faith–are being spent on potentially useless treatments.

(via Medrants)