A lot of people say that the reason the supplement industry is so quirky and unreliable is the lack of regulation. However, I find this to be a catch-22 statement in America, because if an agency such as the FDA is allowed to fully regulate the supplement industry, then you can rest-assured their regulation will be first to get rid of everything that works, and secondly to give exclusive selling rights to pharmaceutical companies who want you to bay $200 for their versions of what you can get right now for 1/10th of the cost or less. I find it hilarious that there's always hooplah about testosterone boosters, particularly, and yet just this summer commercials started coming onto television instructing you to "ask your doctor about low T." Yes, so he can give you steroids.
The main problem is that the single most unbiased group of people who simply search for the right answers, are the people most subject to being forced to abide by the wills of the money-mongers. Those people are you, the customers. And even if you form watch-dog groups, you have to be wary of just becoming another group of lobbyists, at least in the eyes of the "old boys" who currently run things. Private organizations with big charters (like the FDA), will do whatever it takes to make their $$. So will the supplement companies in the current climate. The best thing anyone can do is know someone who isn't just in the know, but will also dig. If a Company has a product that makes a claim, it's not difficult to call them up and ask them "how?" Someone who knows enough biology will be able to either confirm the theory (some companies actually have good theories), or see through the haze of B.S. (Like with the "nanotechnology.")
As for GNC, yes, they're arguably the textbook definition of "Evil American Corporation." But an amusing note right now is they're on the verge of being at War with Pepsico over the whole Gatorade merger. Pepsico being arguably one of the dirtiest Companies I've ever learned of, apparently made products available elsewhere that they promised GNC would be exclusive, and GNC is retaliating by marking all of their Gatorade crap down, which is pissing Pepsico off because they're not getting back as much $$ as they think they should be. Which reminds me, just so it's known here, protein prices are about to go up again. Pepsico and Coca-Cola (who is trying to compete with the Gatorade line) have drained the raw materials market with their buying power. It's already affected smaller Companies like the one I work with locally, and it's going to bring about an across-the-board price increase. So you can thank the soda giants for that.