"P57 is the active ingredient in hoodia. What exactly is P57? Why does it have to come from a plant? Are there other sources other than hoodia?"
In order to really understand what P57 is and what it does, you need degrees in chemistry and biology (which I don't have). I'll explain what I do know about P57 and hopefully this will answer your question.
P57 is a steroidal glycoside. "Steroidal" means acting like a steroid – steroids being a class of hormone that has an effect on the body. A "glycoside" is a molecule where a sugar group is bonded through its anomeric carbon to a non-sugar group by either an oxygen or a nitrogen atom. So P57 is a molecule that acts like a steroid.
Still with me? Okay. P57 didn't have a name before Phytopharm identified it as the active ingredient in hoodia. They're the ones who named it. Their scientists observed that P57 elevates ATP levels in the hypothalamus glands of rats. ATP is the molecule your body uses for energy. So theoretically, P57 makes the hypothalamus think the body has sufficient energy – and therefore doesn't need to eat anymore. This makes weight loss easy!
Hoodia gordonii is the only known source of P57 at this time. Other hoodia species might contain P57, but scientists have yet to study other species (and it took 30 years to isolate P57!).
The hoodia gordonii cactus is currently the only source of P57. The molecule can be synthesized, but the process is extremely expensive and results in only trace amounts of P57. Once again, nature outdoes humanity.
So for the time being, hoodia gordonii is our sole source of P57.
I hope that answers your question. If that wasn't a clear explanation, please email me back.
