If Jessica Simpson indulged in holiday treats this season, she certainly hid it well!

The 40-year-old mother of three showed off her slim figure in an Instagram post on Christmas Day, revealing a dramatic 100-pound weight loss. The star is pictured wearing a red-and-white holiday onesie, which highlights her small frame, and sweatpants that had fallen to her knees.

“So I thought Eric was taking a photo from the waist up…,” Simpson wrote, referring to her husband, Eric Johnson. 

 

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The photo had her followers in a frenzy over her impressive weight loss. Actress Jessica Alba gushed, “You so fit!!!”, while fans inquired about her fitness routine. 

“We all wanna know how did you get so skinny???” one fan asked.

Another echoed the sentiment: “I need to do what she’s doing. Help!”

“How do you stay so thin? You look great,” another follower commented.

Simpson, who’s been scrutinized over the years for her figure (remember the ‘mom jeans’ fiasco?), has used to Instagram account to show off her progress since the birth of her youngest daughter, Birdie Mae, in 2019.

Her personal trainer, Harley Pasternak, told E! News Simpson keeps her legs daisy-duke ready by walking 14,000 steps per day and engaging in full-body workouts.

“We slowly ramped those up; we started really easy and slowly increased them,” Pasternak said of her fitness regimen. “We started with doing a full-body workout, one set of each exercise, not really doing too much intensity per body part and gradually increasing the volume and intensity. Focusing on a few muscle groups per day. Different muscles each day of the week.”

The singer-turned-designer notoriously gained a significant amount of weight with each of her pregnancies, but her trainer says her current fitness routine has Simpson feeling like she did before having children.

“[She’s] in control of everything and [has] such a great attitude of not beating herself up if she doesn’t eat perfectly every day,” Pasternak said.

Simpson credits her children (Maxwell, Ace, and Birdie) for keeping her fit. She told People magazine that chasing her kids around “all day, every day” helps her stay in shape.

“I also have the most active husband ever,” she said. “If you marry an athlete, you got to stay on your feet.”

In her memoir “Open Book,” Simpson touched upon her longstanding body image issues, which began when she entered the music industry as a teenager. According to Simpson, she was encouraged to take diet pills, despite weighing only 118 pounds at the time.

The pressure to stay thin took its toll, she says, but Simpson now leads a healthier lifestyle — which includes abstaining from alcohol. The singer also admitted in her book that she had multiple tummy tucks following the births of her children. 

What do you think about the Instagram post? Are you impressed by her weight loss? Tell us in the comments!