The Reality of the Biggest Loser is on Netflix, find out why host Alison Sweeney left the show and what she does now.

In a new three-part documentary titled Fit for TV: The Reality of the Biggest Loser, Netflix takes a deep-dive into The Biggest Loser, interviewing former contestants, coaches, and health experts to uncover "the true story behind the hit weight loss reality show. "

Netflix is dropping this three-part docuseries called Fit for TV: The Reality of the Biggest Loser on August 15, 2025. If you ever wondered what went down behind the scenes on that show, this is your ticket. You can stream it anywhere, anytime, as long as you’ve got Netflix.

Rachel Frederickson won The Biggest Loser Season 15 in 2014 after losing a staggering 155 pounds, dropping from 260 pounds to just 105, meaning she’d shed nearly 60% of her body weight over the course of the competition. When she stepped on stage at the finale, viewers, fellow contestants, and even the show’s trainers appeared visibly stunned.

Netflix's tell-all docuseries about 'The Biggest Loser' featured interviews with former contestants, trainer Bob Harper and more — but not Jillian Michaels

According to the NHS, coronary heart disease (CHD) is the leading cause of heart attacks, and your chance of developing it is increased by: smoking, a high-fat diet, diabetes, high cholesterol, high blood pressure (hypertension), and being overweight or obese.