I'm sorry but I have to say that people can definitely naturally weigh what the contestants on TBL weigh. I for one used to weigh about 370lbs at my highest. I started losing weight at 331 just short of 2 yrs ago though. As a true fat person if I was given a complete diet overhaul and forced to workout 6-8 hrs a day I would lose a ton of weight fast. It is not due to them having gained weight to be on the show. Where do you think they 'before' pictures come from? They aren't all pics of the same fat kid. They are the people on the show.
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I'm sorry to be rude but I just can't see why being on that show has any benefit to someone who has a hard time gaining weight. Why not be on survivor or be the next girl for Flavor Flav? All those shows require personality too.