Try this link, though, it'll get you right to the actual article.
One of the things that particularly bothers me about these products (besides the almost complete lack of regulation and/or quality control) is the way the promoters use the term "natural" as if that means it can't possibly hurt you! Years ago, a close friend of mine had a yearling foal that died because of eating the leaves of a plant (foxglove)that 'naturally' grew wild in their area...
Not to mention the adverse reactions we get from such 'natural' plants as poison oak/ivy...
Another thing that bothers me about some of the marketers (pushers) of these products is the way so many of them disparage true medical studies on their products. For decades pushers of diet nostrums have ridiculed medical wisdom - or twisted it to suit themselves. I've said before that one person who tried to sell me a ephedrine-based product she was 'distributing' through an MLM gave me a 'doctor's recommendation' - turned out to be a CHIROPRACTOR - not an MD or a nutritionist...like I said before, knowledge is the key to permanent weight loss!