As far as going it doing it on your own, I'm afraid the statistics are not favorable. They're out there if you want to look it up, but it's depressing just how unlikely it is to lose a very large amount of weight and keep it off. That's not to knock anyone who has, it's un-freaking-believable and my hats off to them. It's also not to discourage you from trying.. but I'm a very numbers driven guy, and when I was weighing options and researching this just seemed like the best course of action