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Jillian Michaels is reportedly considering to leave "The Biggest Loser" again. The original trainer on the reality series, who exited the show in 2010 only to return in 2012, is said "deeply concerned about the direction the show has been taking."

A source tells PEOPLE, "She is turned off by the mean-spirited story lines and poor care of the contestants." The source adds, "Michaels wants to distance herself from the Biggest Loser brand. Especially considering what happened with Rachel [Frederickson, season 15 winner], her feeling is that there isn't proper attention paid to the contestants' health or wellness."

Michaels is allegedly also unhappy that she's portrayed as the "bad guy" on the competition series. "The show uses her as the bad guy, and anyone who knows Jillian knows she's not the bad guy at all. She's a loving mother of two kids. She's not the negative person they portray her as," the source explains. "She wants to be in a place where she has more respect."

NBC and "Biggest Loser" came under fire earlier this year after Rachel Frederickson showed drastic weight loss in the season 15 finale. She shed 155 lbs. or 59.62|percent| of her initial weight, prompting people to worry about her health. "One girl on the biggest loser lost so much weight that she looks anorexic...," a Twitter user wrote at the time.

Rachel has since gained 20 pounds. Now weighing 125 pounds, she recently said, "I think I'm at my perfect weight."