The Biggest Loser became a cultural phenomenon when it premiered in 2004 — but the show has been plagued with scandals and controversy as well.
When NBC introduced the show, it followed a group of people deemed overweight who would compete in a 30-week competition. The goal was to lose as many pounds as possible to be crowned “the biggest loser,” but with that came backlash.
Some viewers questioned how contestants were allegedly pushed to lose weight through intense exercise and calorie-restricted diets. Producers — and trainers — who worked on the show denied the accusations, which were explored in Netflix’s August 2025 docuseries Fit for TV: The Reality of the Biggest Loser.
“I will stand behind everything that I’ve ever done on that show,” trainer Bob Harper said in a Fit for TV confessional. “I am proud of what I have done.”
Not everyone involved with the show participated in the tell-all. Jillian Michaels was notably missing, though a message about the trainer’s absence was issued at the end, reading, “Jillian Michaels declined to participate in this documentary.”
Keep scrolling for a breakdown of the scandals and controversy related to The Biggest Loser:
Weight Loss Goals
Each season started with a weigh-in to determine the starting point for each contestant. From there, the participants would take part in comprehensive workout and nutrition plans. There were also challenges introduced to motivate weight loss before another weigh-in.
The biggest concern at the time came from medical professionals who spoke out about how safe weight loss is between 1 and 2 pounds per week. While physician Robert Huizenga was involved in the show, he revealed in Netflix’s tell-all that his insight wasn’t always implemented since contestants were losing more than 10 pounds per week — and sometimes up to 20 to 30 pounds.
A disclaimer was issued at the end of every episode of the show.
“Our contestants were supervised by doctors while participating in the show, and their diet and exercise regimen was tailored to their medical status and their specific needs,” read the statement. “Consult with your own doctor before embarking on any diet or exercise program.”
Going Too Far
After The Biggest Loser skyrocketed to success, several former contestants spoke out about the lengths they went to lose weight. Ryan C. Benson recalled fasting and dehydrating himself while Kai Hibbard told The New York Times that she and other contestants wouldn’t drink water and would find ways to further their weight loss.
Danny Cahill, Joelle Gwynn, Dr. Jen Kerns, Suzanne Mendonca, Olivia Ward, Tracey Yukich and Hannah Young were interviewed for Fit for TV, in which most of them expressed issues with their time on the show. (Clips from various seasons showed contestants having medical emergencies and experiencing health scares while filming the show.)
Many of the former contestants and winners revealed that they struggled to maintain their weight loss long-term after appearing on The Biggest Loser, and some opened up about weighing more after being on the show than before.
Coffeegate
During a 2013 episode of the show, Michaels was accused on the show of cheating by allowing her team to take caffeine pills without doctor’s permission. “I stand by my opinion,” she said at the time. “A caffeine supplement is significantly healthier than unlimited amounts of coffee.”
The show publicly acknowledged that caffeine pills were used in violation of its own rules, and Michaels was reprimanded on screen.
While Michaels stood by her decision on the show, she more recently reflected on what she felt should have been done differently. She told Today Health in 2021 that The Biggest Loser “needed a mental health professional” to better help the contestants.
“I think there was some random guy they could talk to if they needed, but these people needed deep work,” she explained. “When you have someone that weighs 400 pounds, that’s not just an individual who likes pizza. There’s a whole lot going on there emotionally.”
Michaels made it clear that she wouldn’t take back how she approached the show.
“The ones I yelled at are the ones that kept it off,” she argued. “You need them to feel the pain of the way they’ve been living. You need them to have a rock bottom moment where they’re like, ‘I can’t take one more moment.’”
Michaels concluded: “The diet worked amazing. You eat less, you move more, and there you go. The contestants who were unsuccessful when they went home, they had unresolved issues with food.”
Rachel Frederickson’s Transformation
Season 15, which aired in 2013, was infamous for its finale in which winner Frederickson walked out and the trainers reacted in horror at her significant weight loss. After entering the show at 260 pounds, Frederickson was 105 pounds at the finale but regained 20 pounds later amid public concern.
“My self-esteem once again was affected by other people’s voices — this time, the kind that live forever in Facebook posts or written in the pages of magazines,” she wrote in an essay in 2014.
Formal Investigation
The New York Post published an exposé in 2016 with quotes from Gwynn and Mendonca about the challenges that came with being on the show and the aftermath. The report noted that California authorities were looking into allegations that The Biggest Loser had been doping contestants.
NBC dismissed these allegations at the time, and there was no formal investigation. Netflix’s docuseries noted that “no one involved with the show has faced criminal charges for distributing the illegal substances alleged in the New York Post.”
‘Fit for TV’ Docuseries
In August 2025, a Netflix docuseries featured interviews with former contestants, host Alison Sweeney and producers about what went on behind the scenes. Some participants revealed they have continued to struggle with disordered eating and mental health issues since their time on The Biggest Loser.
There were also updates on whether the contestants gained back the weight they lost on the show. Gwynn and Mendonca specifically spoke about their decision to use Ozempic to help lose weight and curb their hunger.
