The companies that claim their product is pure do not have to prove it to anyone, so they could easily be lying. If they are telling the truth, then they are obtaining it illegally. Illegal harvest of hoodia is a big problem that they are trying to control. It could hasten the extinction of the plant, as well as similar looking varieties of Hoodia that don't have P57 but are harvested in error. Plus, the San people (among the poorest people on Earth) cannot benefit financially, so it's stealing from them (IMO).
When you order these products, it's like taking candy from strangers. You have no idea what you are getting, or if the mystery product is even safe for consumption. Even if it IS pure hoodia, it is unlikely that it will accomplish the same thing as the fresh hoodia chunks that are eaten by the San people.
(see this post) It doesn't contain enough of the active ingredient in those tiny capsules to work. If it was a simple as drying the plant and turning it into powder for capsules, Phtopharm would have marketed it a long time ago. Instead, Phtypharm and Pfizer couldn't do it, so Pfizter pulled out of the deal. Just imagine the billions of dollars they could have made if it were that easy.
