Filmmaker Kevin Smith in 2008, left, and in 2015. The director of "Clerks" and other movies tweeted in June 2015 that he lost 85 pounds. His secret? Walking 5 miles daily and giving up sugary drinks. In August 2018 he shared on social media that a plant based diet helped him shed 51 more pounds after he suffered a heart attack earlier in the year.
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Kelly Clarkson has always been clear she doesn't care what people have to say about her weight. In 2018 the singer/ "The Voice" coach showed off a more slender figure and joked that she had "literally hired Harry Potter and SPANX, it's all like a sausage."
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Actor Craig Robinson said in October 2017 that he lost 50 lbs. by giving up alcohol, working out and going vegan.
Macaulay Culkin's new look is winning rave reviews from fans. The actor was spotted in July 2017 having gained weight and cut his hair. The child star, seen on the left in 2014, looked so gaunt in 2012 there was speculation he was on drugs - which he denied.
Jonah Hill fans immediately noticed the actor's new summer bod for 2017 and applauded his fit overhaul as inspiring. Hill credited his recent slim down to advice from "21 Jump Street" co-star Channing Tatum.
"Girls" star Lena Dunham showed off a slimmer physique in March 2017 on the red carpet for the opening of celebrity fitness trainer Tracy Anderson's new studio in New York City.
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Talk show host Wendy Williams lost 50 lbs over three years and said in February 2017 that she is keeping the weight off.
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Lil' Kim, left, at a 2003 BET event, has stirred controversy over her changing appearance in the past, but these days she's unrecognizable -- and people are talking.
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If you know Chris Hemsworth as the mighty Thor -- at left in 2011 -- his diminished size and scraggly face for the upcoming film "In the Heart of the Sea" might come as a shock. Hemsworth tweeted the photo on the right in November 2015. "Just tried a new diet/training program called 'Lost At Sea.' Wouldn't recommend it," he wrote.
"Roseanne" star John Goodman is known for his burly frame in addition to his acting chops. Goodman has slimmed down noticeably, as was evident at a screening of "Trumbo" in October 2015. The photo on the left was snapped just a year earlier at a showing of "The Gambler."
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Shonda Rhimes, creator and producer of such hit shows as "Grey's Anatomy," "Scandal" and "How to Get Away with Murder," has undergone quite a transformation. She credits diet and exercise for her loss of more than 100 pounds.
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Melissa McCarthy has been shedding weight, and she told Gayle King on "CBS This Morning" that she simply stopped stressing over it. "I feel amazing ... and I finally said, 'Oh, for God's sake, stop worrying about it,' and it may be the best thing I've ever done," she said.
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Matthew Lewis, who starred as the shy and unassuming Neville Longbottom in the "Harry Potter" movies, has grown into a strapping young man. He buffed up for roles as a soldier in "Bluestone 42" and an athlete in "Me Before You."
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Penn Jillette told People magazine there was no magic involved in his weight loss from 330 to 225 pounds. The performer, who is half of the illusionist act Penn & Teller, just changed his eating habits to shed 105 pounds and get his high blood pressure under control.
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