Hi Ed,
They may be good for some people but could have serious consequences for people with impaired livers (like me with Hep C). It can also change the effectiveness of chemotherapy treatment.

I work as an FDA consultant and I have to agree with Brian than this food supplement loophole has got to be stopped. Why companies are allowed to promote medical benefit of unproven and potentially dangerous herbs and other food supplements is one of the dark sides of the regulatory business and congressional and political meddling with the FDA. Using some logic here - if an herb really DID have curative powers, why wouldn't a company WANT to do the clinical trials to prove it - they would make billions! The deceptive, testimonial style of marketing is the tip off.