Jessica Simpson's trainer defends singer's unhealthy weight loss

Jessica Simpson has sparked concern over her drastic weight loss these days.

Several paparazzi clicks showed the 42-year-old singer in skintight dresses, looking skinnier than ever, however, the final blow served when fans noticed Simpson wearing one of her jackets from when she was eight.

"At 42, with three children, what woman fits into clothes she wore as a child?” a fan wondered. "Someone [needs to] step in and help her."

Meanwhile, a source told RadarOnline that people in her inner circle, including friends and family, are "extremely worried about her.”

Simpson previously revealed that she lost over 100 pounds following the birth of her daughter Birdie three years ago.

"But she continues to lose more and more weight, and it's alarming," the insider added.

Jessica's longtime trainer, Harley Pasternak, insisted Jessica’s weight loss isn’t as alarming.

"My mantra is you get lean in life and strong in the gym," he said. "So the majority of the weight loss actually came from everything she did outside of the gym [as far as being active], and then everything in the gym is about toning and tightening."