She's the new coach on The Voice, but all eyes are on her impressive body. Kelly Clarkson has undergone an extreme slimdown in just a few months, and fans can't get over her weight loss transformation. The "Stronger" singer recently shared some backstage photos of her on The Voice, and fans couldn't help but comment on Kelly's figure. "You look so amazing, I’m so proud of you!" one user wrote. "Every episode of The Voice you’re looking happier and healthier, way to go, girl," another said. "@kellyclarkson you look great! How much weight have you lost? Great job!" a third wrote.

But how much weight has Kelly Clarkson lost? "Kelly looks like she's lost 40 pounds!" fitness coach Nadia Murdock Fit says. "You can definitely tell there was a dramatic weight loss." Inaugural American Idol winner Kelly, 35, has battled weight issues for years, especially since giving birth to daughter River in 2014 and son Remington in 2016. But she's embraced her body type, telling Redbook last year, "when I'm fat… I'm happy."

kelly clarkson before and after weight loss 2

Still, Kelly decided it was time for a change. "She started losing weight four months ago," a source tells Life & Style. "She's been working out with a trainer four times a week." Kelly has turned to experts to help with her diet, too.

kelly clarkson weight

"I don't cook," she tells Life & Style. "We have a chef and her name is Lisa and she makes these amazing things." Amazing — and healthy. "Kelly has cut back on junk food," the source adds. "She's been living on a high-protein diet and has swapped sugary treats for raw vegetables." Sounds like a lot of hard work and sacrifice — but as Kelly says, what doesn't kill you makes you stronger.

Check out more before and after photos of Kelly Clarkson's weight loss transformation below.

kelly clarkson before and after weight loss

Kelly in 2017 vs. 2018.

It's great to see Kelly taking control of her health. The singer revealed last year how she was cruelly fat-shamed while competing on Idol. "Even on American Idol I was really thin, but I was bigger than the other girls on the show, so people would say things to me," she told People. "But luckily I am super confident, so I've never had a problem with shutting people down and saying, 'Yeah, you know, that's just what I'm rocking. It's fine.'" Good for you, Kelly!

Watch the video below to learn why Kelly decided to join The Voice.