Jillian Michaels Dropping Out of 'Biggest Loser'

"The Biggest Loser" is about to shed another 120 or so pounds...and they all belong to Jillian Michaels.

The weight loss competition show's most famous trainer will not be back for the upcoming season. According to a statement from NBC: "After helping hundreds of contestants transform their lives and inspiring millions of viewers at home, 'The Biggest Loser' and Jillian Michaels have decided to part ways and she will not be returning for season 16 when it airs in the fall."

This is actually the third time that Michaels has left the show; back in 2006, she left for a year and returned in 2007, and then left again in 2011, missing two seasons. Two more seasons later, Jillian is hitting the road again.

While neither Michaels nor NBC has given an official reason for the split, sources close to Michaels are claiming that the most recent season upset Michaels to the point where she doesn't want to continue with the show. In particular, sources say, Michaels was upset with the lack of oversight over the contestants' at-home weight loss efforts before the finale, which led to the season 15 winner, 22-year-old Rachel Fredricksen, losing an alarming amount of weight.

Fredricksen started the show at 260 pounds and lost 155, weighing in at the finale at only 105 pounds. At 5'4" and thus with a BMI of just 18, that means that Fredricksen would likely have been considered underweight by the majority of health professionals.

Michaels made her issues with the way the show had been run known in an interview after the finale. "Obviously, I thought she had lost too much weight and I was immediately concerned and wondering how this happened," she said, "how no one had said something to me and how the checks and balances that have been put into place, in my opinion, this had fallen through those checks and balances."

There are no details yet as to who will take over Michaels' place as the third team trainer. However, with the season 16 premiere set for this September, we'll likely be hearing news soon.