Here are 7 incredible celebrity weight loss transformations that might surprise you. Let's find out who these celebrities are!

From Jenny Craig to Weight Watchers, celebrities are hopping on the weight-loss bandwagon and getting paid big bucks to do it. But money aside, many stars are shedding the pounds in pursuit of healthier lives.

With the help of diet and exercise (and in some cases, surgery) these celebrities have gone through extremely impressive transformations.

Khloe Kardashian

[caption id="attachment_375" align="aligncenter" width="416"]Khloe Kardashian Before and After a weight loss                        Khloe Kardashian Before and After[/caption]

You may remember Khloe as being bigger than her sisters, but those days are long gone. ET says this Kardashian lost 40 pounds overall by making nutrition and fitness a priority after her painful divorce. “By keeping positive about your body, your inner health, your mental sanity, your fitness, and what you’re trying to achieve, you’re way more likely to succeed,” she said.

Adele 

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The "Hello" singer has made headlines recently for showing off her dramatic transformation after she reportedly said she knew "she had to change something". While spotted on vacation, Adele reportedly told fans that she'd lost 100 pounds, and her former trainer recently explained that the weight loss "was about getting her healthy" rather than the publicity stunt she was accused of orchestrating as her album is rumored to drop this year.

Jonah Hill

[caption id="attachment_377" align="aligncenter" width="538"]Jonah Hill Before and After a weight loss                                                       Jonah Hill Before and After[/caption]

This celeb’s weight yo-yos for roles. But right now, Jonah Hill looks slimmer than ever. Us Weekly says Hill gained 40 pounds for his role in War Dogs, but he’s since lost the weight by keeping a food journal and listening to his nutritionist. He also got feedback from Channing Tatum, who suggested eating less and getting a personal trainer.

Rebel Wilson

[caption id="attachment_382" align="aligncenter" width="504"]Rebel Wilson Before and After a weight loss                                        Rebel Wilson Before and After[/caption]

After declaring 2020 her "year of health," the 39-year-old actress began a health and diet regimen that's provided great results. Wilson shared a photo of herself at the beginning of the year on the beach, just as she was beginning her weight loss journey. Wilson said she's "deliberately hydrating" and "trying to avoid the sugar and junk food." A few weeks later, Wilson's trainer shared a photo of the actress in all black athletic-wear, as well as a video of her training with Cross-fit ropes.

Chris Pratt

[caption id="attachment_385" align="aligncenter" width="443"]Chris Pratt Before and After a weight loss                                     Chris Pratt Before and After[/caption]

Fans loved Chris Pratt before he lost weight. But now, the Guardians of the Galaxy star looks better than ever. Men’s Fitness reports he lost around 60 pounds in six months with his extreme workout plan. Pratt’s workouts include P90X and cardio like running, swimming, and participating in triathlons. And actor doesn’t cut calories; the father of one eats around 4,000 calories a day when he’s training, and he drinks a ton of water.

Jessica Simpson 

[caption id="attachment_387" align="aligncenter" width="445"]Jessica Simpsons Before and After a weight loss                                  Jessica Simpsons Before and After[/caption]

During Jessica Simpson’s first pregnancy, she gained 70 pounds, which doesn’t come off easy. But thanks to a healthy diet and lots of exercise, she looks better than ever after having two kids. Fox News reports she eats healthy and works out five days a week (a mix of strength training and cardio with a trainer for three days each week). She also says she never has a specific goal weight in mind; she just wants to look and feel healthy, which she has accomplished.

Christina Aguilera

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The singer shed nearly 50 pounds back in 2013. She took time off from The Voice to do it—"it’s amazing what having some personal time can do, not only for the body but also for the mind and the spirit," a source told People. "She has been trying new types of foods and exploring new methods of exercise. Not for diet or weight, but more for her mind and well being and overall sense of good health." Aguilera also credits reiki, an ancient Asian practice that’s said to heal your body and mind, for her weight loss.

These 7 incredible celebrity weight loss transformations not only surprise us but also become a source of inspiration for all of us to maintain a healthier lifestyle.