Alternative Medicine Update: Chelation therapy, the alternative medicine practice of using the chemical EDTA to bind heavy metals in the blood to treat heart disease, gets its own large, prospective study this spring. Quackwatch has a nice review of the subject: what it is, the theories behind it, and how it's currently practiced. As it stands now, the doctors who use this aren't basing their practice on any sort of evidence, only on theory. The study by the NIH is a welcome one, especially since it's apparently being designed by someone who has no vested interest in the outcome.