INSIDE EDITION spoke to contestants who've struggled to keep the weight off.
While contestants on The Biggest Loser have shed hundreds of pounds of weight over the years, many of them are unable to keep it off.
Doctors followed 14 contestants who appeared on the show in 2009. Incredibly, the doctors determined that nearly all of them have put weight back on.
Read: Amy Schumer Reveals Her Trick For Staying Cool on The Red Carpet
Contestant Danny Cahill inspired America by losing the most weight in the history of the show. He lost an incredible 240 pounds in seven months during the fall 2009 season.
"I was thinking, 'It’s over. I'm normal now. I lost 240 pounds and now I can live a normal life like everybody else,'” he told INSIDE EDITION.
Cahill has gained 100 pounds since leaving the show.
Amanda Arlauskas lost 87 pounds in the same season Cahill broke the series record.
Even though she works out hard every day and has watched her diet since leaving the show, she's gained back roughly 12 pounds.
“To be about 12 to 15 pounds above my finale weight and have to work my ass off to keep it that way, I knew something was wrong,” she admitted to IE.
Tracey Yukich lost 118 pounds during the 10th season of the show but since then she's gained back 46 pounds.
"We are not normal. We have to do extra. It is not going to be this quick fix and it is going to go back to the way when we were athletic and in high school," she told IE.
One contestant, Sean Algaier, actually weighs more than the 444 pounds he weighed in with at the 2009 season premiere.
Read: Amy Schumer Lashes Out at Glamour Magazine for Including Her In Plus-Size Issue
Obesity expert Dr. Michael Schwartz says the study proves that it may be almost impossible for obese people who lose weight to keep it off.
"As a result of weight loss, the metabolism of those contestants dropped a lot. On average, weight loss from this type of intervention will tend to be regained," he told IE.
For the contestants of the hit show, the new study is a life changer— it means they can stop blaming themselves for their weight gain.
"Two weeks ago, I would not want to be on camera with you because I have gained weight back," Cahill told IE. "The moment that report came out, I said I have to go on camera, this has to be said. The shame came off my shoulders and it is time to speak up."
Watch: Students Remember Late Teacher Who Lost 180 Pounds on 'Extreme Weight Loss'
