Is 'Biggest Loser' Winner Rachel Frederickson Too Thin?

NBCWhen "The Biggest Loser" winner Rachel Frederickson revealed her 105-pound body on Tuesday night after dropping an astonishing 155 pounds from her 5’5" frame, the world collectively gasped. Her transformation, which visibly shocked the show's judges, quickly triggered a heated debate about how much is too much when it comes to weight loss.

On Wednesday, 24-year-old Frederickson, told Us Weekly that she was thrilled about her new slender frame. "I’ve never felt this great, and it’s very exciting! Now I’m really at maintenance mode, so now it’s gonna be about doing a yoga class this day, a spin class this day, and I think I’m going to try dance classes because I don’t have a lot of rhythm, but I think it’d be fun to just add totally new things in!"

"The Biggest Loser," in its 10th year, is shot over a seven-month period and pits overweight contestants against each other in the reality TV weight-loss competition show. At the beginning of each season, contestants are grouped into various teams, each working with a celebrity trainer who tailors nutrition and exercise programs to each player. Along the way, the weight-loss hopefuls are faced with challenges that tempt their willpower (often with sweets and cash). The person with the steeliest resolve who drops the most weight is dubbed “The Biggest Loser" and awarded a $250,000 grand prize.

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The show has been slammed for turning weight loss into a competitive sport and exceeding the medical recommended limit (shedding 1 to 2 pounds per week), since some contestants drop almost a dozen pounds per week. As for Frederickson, a former national level swimmer who gained weight after experiencing a painful breakup, many viewers have responded to her serious slimdown with shock, taking to social media to call out her transformation as unhealthy. Others have defended Frederickson, scolding her critics for being too judgmental.

But is Frederickson too thin? According to the Centers for Disease Control (CDC), a normal, healthy weight for a 5’5 woman can range anywhere from 111 to 150 pounds, depending on her frame. And at 105 pounds, Frederickson isn’t too far off. 

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“There are so many variables to Frederickson’s weight loss that it’s difficult to say whether she is unhealthy,” Ashley Borden, a Los Angeles-based fitness and lifestyle coach, tells Yahoo Shine. “We don’t know her muscle mass, her body-fat percentage, or how she plans to maintain her weight beyond the show's finale.” What’s more, unlike the average person. who might have time to squeeze in a gym session several times per week, "The Biggest Loser" contestants exercise for hours a day, seven days a week. 

One reason the public may be stunned at Frederickson's figure is that we’ve seen her at her heaviest. “If you saw her in line at Starbucks would you gape at how thin she is, or would you not give it a second thought?” asks Borden, who adds that it’s common for former athletes to undergo extreme weight loss once they’re reignited with that familiar sense of competition.  

The important thing for Frederickson to remember, says Borden, is that her new body is just the packaging. "If she doesn't work on the issues that caused her to gain weight," she says, "she could easily end up in the same place she started."

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