From PEOPLE Magazine Click to enlarge
260 LBS.

4 months

150 LBS.

3½ months

105 LBS.

As a contestant on The Biggest Loser, Rachel Frederickson bared her 260-lb. body in nothing but a sports bra and shorts, shared her heartache about a bad breakup and fought her way through dozens of grueling workouts. Still, nothing could have prepared the 24-year-old voiceover actress for the tidal wave of criticism and scrutiny that has engulfed her since revealing her 155-lb. weight loss on the reality show's Feb. 4 finale. Dressed for the mild Los Angeles winter in skinny jeans, knee-high boots and a zip-up sweater just three days after the big reveal, the new champ—nursing a glass of orange juice during the 90-minute interview - is mostly upbeat, using Biggest Loser-speak to address her new size 0-2 body. "I am proud of my journey and excited for this new life," she says. But she grows quiet when asked about the shock that registered on the faces of trainers Jillian Michaels and Bob Harper at the moment of her reveal, admitting that the overall response to her transformation has been "overwhelming. It's been quite a whirlwind."

It has also ignited the biggest controversy in The Biggest Loser's 15-season history, raising questions about Frederickson's health and the NBC reality competition's safety. Having dropped 45 lbs. in the three and a half months before the finale, the 5'4" Frederickson's winning weight of 105 lbs. puts her Body Mass Index at 18, just below what the CDC considers normal. Producers say she was carefully monitored throughout her nearly yearlong tenure with the show, including in the days before the finale. "Rachel passed all the required medical tests, ensuring she was healthy," says the show's executive producer Dave Broome. "The health and well-being of our contestants is our No. 1 priority."

Beyond the numbers, Frederickson's lined face and visibly bony arms alarmed many viewers, experts and even some at the show - among them host Alison Sweeney, who tells PEOPLE, "I understand and shared in the concern for Rachel at the finale. My hope is that she and all show contestants achieve lifelong health." Frederickson's trainer Dolvett Quince, who had last seen her when she left the Biggest Loser ranch in mid-October, says, "I was shocked. The first thing that went through my mind was, 'That's just too much.' " Frederickson concedes she "maybe was a little too enthusiastic" with her training. "I worked out six hours a day," she admits. But she insists she stuck to Quince's recommended 1,600 daily calorie allotment after leaving the ranch. "My breakfast would be healthy French toast or an omelet," she says. For her sweet tooth, "I love to make lemon slushies. I'll cut half a lemon and put in Stevia and ice. That was my go-to."

Asked point blank whether she has an eating disorder, she replies, "I am very, very healthy." Has she experienced any troubling signs of extreme weight loss, such as dehydration, a disrupted menstrual cycle or hair loss? "No. I've never felt better. I keep saying it: I am healthy."

But according to several insiders, there were some who were "horrified" by Frederickson's size in the days leading up to the finale. Still, the show's producers "honestly thought maybe she'd look okay and no one would notice - but people gasped," says a source who works closely with Loser. "What's worse is that she doesn't seem to recognize she's gone too far." But Broome says even after seeing Frederickson "a few days" prior to the Feb. 2 reveal, "we never considered not letting her appear in the finale." As for Frederickson's flowy dress - a stark contrast to the form-fitting looks worn by past winners - she says it was her choice: "I felt like I shined in it."

Before auditioning for the show, it had been a long time since Frederickson felt comfortable in the spotlight. An athletic, "bubbly" kid growing up in Oakdale, Minn., she swam competitively until age 18, when she moved to Germany to join a boyfriend she'd met in high school. "I just lost myself," she says of the romance. By the time she returned to the U.S. six months later, she was up 10 lbs. from her swimming weight of 135. Reflecting on her weight gain in the years since, she says, "Being on Biggest Loser, I realized the emotions I pushed aside with food are being overwhelmed and stressed. I never took care of me."

But critics say The Biggest Loser's high-stakes format—rapid weight loss with a $250,000 payoff for the contestant who loses the most—can be damaging. Kai Hibbard, 35, an outspoken opponent of the show who lost 118 lbs. as a finalist in season 3, says she was encouraged to "crash diet" on the ranch. She also says that when she told her trainer Kim Lyons that she wasn't sleeping and had stopped menstruating, Lyons advised her to "suck it up and get back on the treadmill." Lyons, who no longer works on the show, refutes the claim, saying, "I would never tell anyone that was concerned for their health to get on a treadmill." (NBC had no comment on Hibbard's accusations.)

Others take issue with the show's intense obstacle course–style workouts. "The truth is, the key to losing weight does not make for good TV," says celebrity trainer Harley Pasternak. "Taking 10,000 steps a day, eating smaller portions - how do you make a healthy smoothie exciting TV? It's impossible."

Both supporters and opponents of the show agree that a key challenge for contestants is transitioning from highly regimented ranch life to the real world. "The Biggest Loser system is that we take you out of your reality and put you on this island," says Quince. During their time on the ranch, "contestants are closely monitored and medically supervised" by a doctor, psychologist, registered dietician and trainers, says Broome. In the three months between leaving the ranch and appearing on the finale, Frederickson had weekly call-ins with the team of professionals. Additionally, "I had cell phone numbers for them, and they said to call anytime," says Patrick House, the season 10 champ.

Now that the show is over, Quince wants to continue offering that support to Frederickson. "We had the conversation about getting her body back to a place where she has energy and muscle mass," he says. "I'm not trying to lose any more weight," says Frederickson, who plans to scale back her workouts to around 90 minutes a day. As for her weight, "I'm just kind of finding where it all settles," she says. "I was a contestant, and I trained like an athlete for the finale. Now I am a girl in her real life."

  • Contributors:
  • Patrick Gomez/Los Angeles,
  • Raha Lewis/Los Angeles,
  • Melody Chiu/Los Angeles,
  • Gabrielle Olya/Los Angeles,
  • Kate Coyne/New York.