'The Biggest Losers': Before and after

When "The Biggest Loser" contestant Rachel Frederickson showed just how much weight she lost on the NBC competition in season 15 -- 155 pounds, to be exact -- not everyone was impressed. A number of viewers expressed concern that she had become "too skinny," although Frederickson said that she feels fine. As we welcome in a new season of competitors, let's catch up with the rest of the "Biggest Loser" winners:

When "The Biggest Loser" contestant Rachel Frederickson showed just how much weight she lost on the NBC competition in season 15 -- 155 pounds, to be exact -- not everyone was impressed. A number of viewers expressed concern that she had become "too skinny," although Frederickson said that she feels fine. As we welcome in a new season of competitors, let's catch up with the rest of the "Biggest Loser" winners: