Biggest Loser Finale

I am so hooked on this show. I could not believe how much everyone lost! That one chick, Poppi from New Jersey, looked completely different. She looked like a little girl! The winner Erik, holy cow. How does someone lose over 200lbs in 9 months? I enjoy the show and it inspires me, but sometimes I wonder how healthy the diet is. I feel like the quicker you lose the weight, the easier it is to gain it back. I did see the winner from last season, Matt, in last weeks episode and it looked like he gained a lot back. So I am curious of the success rate of those who lost and managed to keep it off. I mean, they workout so intensely while they are on the ranch, how is it possible to keep up that intensity at home, while living your life? I think that those contestants that didn't make it on the ranch but still lost weight will probably have a better chance of keeping it off. But who knows? They were all competing for this. So now that the competition is over, will they not work at it as hard? I also think that ALL of the contestants had gotten a lot of help that the average person would have (gym membership, regular personal training, nutritionist). So now that the competition is over, will the show continue to pay for that stuff? I still love the show and will watch it if they have another season, but I just wonder about how real it REALLY is.