Celebrities have inspired a lot of people with their weight loss journeys. Check out these before-and-after photos of famous people who've lost dramatic amounts of weight over the years, starting with this celebrity scion and author… TV host and former "Fashion Police" Star Kelly Osbourne, seen here in 2006, struggled with her weight for years before finally making a lifestyle change around 2009. Keep reading to see her transformation over the years — including the results of her significant surgery-sparked weight loss in 2020…

Then keep reading to see dozens more celebs who've lost a lot of weight…

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In 2012, Kelly Osbourne dropped about 70 pounds and shifted to a plant-based diet as she was dating a vegan chef at the time. She kept off the weight for a while but has long been open about her struggles, which have been complicated by her sobriety journey. In 2020, she Revealed how she'd achieved another huge weight-loss goal and debuted a dramatically slimmed-down look.

See it next…

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In August 2020, fans noticed that Kelly Osbourne (seen here in October 2020) was looking slimmer than ever in some of her Instagram photos, which led Kelly to confirm that she'd indeed lost a significant amount of weight — 85 pounds, she said. Days later on an episode of the "Hollywood Raw" podcast, the TV host revealed she'd undergone gastric sleeve surgery to help her achieve her weight-loss goal. "All it does is change the shape of your stomach. I got that almost two years ago," she said, adding, "I will never, ever, ever lie about it ever. It is the best thing I have ever done." She explained that she "had to do a year of stand-alone therapy to prepare myself for the surgery before I even had it. What people don't realize is it cuts out this hormone that if you have addiction issues, it stops your craving, and it makes you not emotionally eat, and that was a huge problem for me." She said getting sober beforehand helped and warned, "All [the surgery] is is a push in the right direction. It doesn't solve all your problems… It's not a quick fix."

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In March 2021, "Perfect Strangers" alum Bronson Pinchot revealed he'd lost an incredible 60 pounds, sharing the before-and-after photos on Instagram. The first pic (seen here) was taken in 2017 when he was filming "Battle of the Network Stars." He told Page Six that he started his slim-down in May 2020 after he saw the snapshot shortly after coronavirus lockdowns began and thought, "There was an old fat guy." The "Chilling Adventures of Sabrina" actor — who's now vegan — said he went through his pantry and fridge and got rid of all the junk food "and then I just put healthy food in the house and I said, 'OK, puppy, you can have whatever's there.'" It was difficult — he admitted he sometimes couldn't sleep because of hunger pangs — but in six months, he'd dropped the weight by following a "self-designed healthy plant-based eating program," he explained on Instagram.

Bronson Pinchot posted this photo of himself on Instagram on March 8, 2021, revealing the results of his 60-pound weight loss. He told Page Six that after slimming down, he went through a box of clothing and mementos from his time playing Balki Bartokomous on ABC's "Perfect Strangers" from 1986 to 1993 — he hadn't touched it for 25 years — and tried on a few things. "And they fit," he said. "And I thought, 'I'm pretty sure I'm the only 61-year-old within a 10-mile radius that's getting into his clothes from when he was a 26-year-old doing two aerobics classes a day.' And that feels pretty good. That feels pretty good."

"Pawn Stars" personality Austin "Chumlee" Russell struggled with his weight for years. He hit 350 pounds in January 2019, he told TMZ in October 2021, and a month later underwent gastric sleeve surgery at Blossom Bariatrics in Las Vegas. Over the next two and a half years, he lost nearly half his body weight…

On Oct. 7, 2021, Austin "Chumlee" Russell showed of his incredible body transformation at "The Original Immersive Van Gogh Exhibit Las Vegas" at Lighthouse Las Vegas at the Shops At Crystals. The same month, he revealed to TMZ that he'd shed 160 pounds since undergoing gastric sleeve surgery in early 2019, putting him at 190 pounds.

Christopher Schwarzenegger — the youngest son of movie star and former California governor Arnold Schwarzenegger and his estranged wife, journalist-author (and Kennedy family member) Maria Shriver — is seen here in Los Angeles in August 2018. Keep reading to see his transformation three years later…

A slimmed-down Christopher Schwarzenegger was photographed in Los Angeles on Oct. 5, 2021, after getting a pedicure at a nail salon with mom Maria Shriver and sister Christina Schwarzenegger. A week earlier, dad Arnold Schwarzenegger appeared to reveal how Christopher's achieved his weight loss, writing in the caption of an Instagram post marking his son's 24th birthday, "Happy birthday Christopher! I love you and I'm proud of you every day! You're so smart, and you have such a big heart. Between your boxing classes, your weightlifting classes, your stretching classes, your cycling classes, and on and on, I can't even keep up with you! I can't wait to see what you accomplish this year."

Although she's used her size as fuel for jokes, comedic actress Rebel Wilson has slowly been trimming down in recent years. Here's what Rebel looked like in May 2013. Keep reading to see her three years later and again in 2020 and 2021 — including in some brand new September photos — as her health transformation continued…

Like many stars, Rebel Wilson has addressed her weight loss on social media. In April 2016, she shared info about losing a few pounds at a luxury bootcamp in Malibu. "OMG just finished 4 fantastic days at #TheRanch4.0…so challenging but very rewarding!" she wrote on Instagram. "Not to mention I lost 8 pounds from marathon hiking over the 4 days!" Rebel, seen here in December 2017, has continued to put in the work. In January 2020, she revealed that "for me 2020 is going to be called 'The Year of Health'" and that she was working hard to get to a goal weight of 165 pounds by the end of the year. All 2020 long, she posted photos of her weight-loss progress on Instagram and soon was showing off her progress on the red carpet…

In September 2020, Rebel Wilson revealed her slimmer, trimmer figure at the Monte-Carlo Gala For Planetary Health in Monaco. A month earlier, she posted a photo of her slim-down progress on Instagram, captioning it, "Thanks for all the love so far on my 'Year of Health' journey — when I was reaching for the candies last night after dinner I thought to myself 'hmmmm…better not' and had a bottle of water instead x 8kg's [just over 17 pounds] to go until I hit my goal — hopefully I can do it by the end of the year x."

Rebel Wilson's incredible slimdown continued in 2021. She shared this Instagram photo of herself posing in a swimsuit in Palm Beach, Florida, on May 31, 2021…

…and Rebel Wilson is seen here filming the comedy "Senior Year" in Atlanta, Georgia, on June 10, 2021, as her slimdown continued.

Rebel Wilson looked glamorous and svelte at the Academy Museum of Motion Pictures premiere party in Los Angeles on Sept. 29, 2021. Two months earlier in an Instagram live, she revealed she was down "like 70 pounds, 75 pounds, maybe a bit more." A month after that, she posted a throwback photo of herself at her "most unhealthiest" and explained why she shared it, telling fans, "just wanted to send out some encouragement to everyone out there struggling with weight or body issues or emotional eating. I feel you. I know what it's like. But it's never too late to start improving yourself and trying to be the best version of YOU possible. It's not a race and it's not a competition — it's about respecting yourself and doing what's best for YOU. So if you're out there and reading this today, I just wanted to say: keep smiling and keep trying to be active!"

Keep reading to see how her beautiful face has transformed…

Rebel Wilson looked gorgeous at the Academy Museum of Motion Pictures premiere party in Los Angeles on Sept. 29, 2021.

"Pioneer Woman" star and cookbook author Ree Drummond took to TikTok on May 16, 2021, to share the results of her ongoing 2021 weight loss journey. "I can't get away from food and I love to eat. Of course it crept up on me through the years, especially during COVID," Ree (seen here in 2019) told her followers in a short video. "So, starting in January, I decided to get busy and lose some weight." Keep reading to find out how much Ree lost over the next four to five months…

"The Pioneer Woman" star Ree Drummond shared the results of her health and weight loss journey in May 2021 in a video she shared on TikTok in which she revealed she'd lost 38 pounds since January 2021. So how'd she do it? "No gimmicks at all. I just cut calories, exercised more, lifted a lot of weights," she said. "I look better but I feel so much better and that's what really counts." On June 15, 2021 the self-described "lover of food and avoider of exercise" shared specific details of her slimdown — at that point she'd dropped 43 pounds — in a lengthy blog post titled "How I Lost Weight (More Importantly: How I Got Healthier!)" in which she explained, "In January, just before I bit the bullet and took the leap, I was tired, puffy, and desperate…and I knew I shouldn't be feeling that way."

Rapper Tekashi 6ix9ine revealed his dramatic weight gain — and loss — in a February 2021 Instagram slideshow. In March 2021, he told TMZ that he weighed 134 pounds when he was released from prison in April 2020 and immediately started packing on the pounds. "I was eating Chinese food every day, twice a day on house arrest," he said, explaining that his weight shot up to 204 pounds by September 2020. He didn't post any photos of himself on social media for five months, then suddenly returned in late February 2021 to reveal the truth of why he was away — and share that he'd lost 60 pounds and was down to 146. "People who don't want to lose weight make a whole bunch of excuses," he told TMZ before offering controversial and not-recommended diet advice: "Starve yourself," he said, "and work out." He also told TMZ he cheated on his diet every three days to treat himself to Gushers candy.

Back in 2012, fashion designer Karl Lagerfeld rudely called Adele (seen here in 2008) "a little too fat." The following year, he said the Grammy winner was "roundish." Fans were appalled, but the singer claimed she was never affected by fat-shaming. "I've never seen magazine covers or music videos and been like, 'I need to look like that to be a success,'" she told "60 Minutes" in 2012. "I don't want to be some skinny mini with my t*** out. I really don't want to do it and I don't want people confusing what it is that I'm about." But she did make some personal changes for her health after she became a mom. Keep reading to see her transformation in 2015 and how she took things further in 2020…

At the same time Adele dropped "Hello" — her first new single in three years — in 2015, she revealed she'd dropped a few pounds as well. Although she never shared how much weight she lost, the results were apparent. The Grammy winner reportedly adhered to a vegetarian diet and went on daily runs — she also hit the gym to prep for a world tour. In late 2019 and early 2020, new photos of the singer — including some she posted on Instagram herself — revealed she'd lost even more weight: reportedly 100 pounds! Next, see her in October 2020…

Adele delivered laughs (but no new music!) when she hosted NBC's "Saturday Night Live" on Oct. 24, 2020. During her monologue, she showed off her trim figure and quipped, "I know I look really, really different since you last saw me but actually, because of all the COVID restrictions and the travel bans, I had to travel light and only bring half of me — and this is the half I chose."

TV host and reality TV staple Ross Mathews, who came to fame as "Ross the Intern" on "The Tonight Show With Jay Leno," has long struggled with his weight. When he was around 220 pounds in 2010, he joined Jenny Craig after friend Gwyneth Paltrow "pointed at my tummy and said, 'What's going on here? I love you. Get it together,'" Ross told People magazine in 2011. Though his weight has fluctuated since then, Ross — seen here in May 2015 — did some serious work and dropped 50 pounds in 2020!

On Nov. 29, 2020, Ross Mathews took to Instagram to share this photo and a message explaining his major weight loss and attitude about it. "Breaking the pattern. 50lbs down today from my height in early June when I decided to reclaim my health after my mom died (70lbs down from my all-time)," he wrote. "I will always be a work in progress. I may mess up again. I dunno. All I know is that I'm very grateful. And very happy. 🥰 On we go… ❤️."

Comedian Tiffany Haddish looked pretty darn good to us when she hit the red carpet for a fashion week party in September 2019. But a year later, she looked — and felt — even better. See Tiffany 40 pounds lighter…

Tiffany Haddish — seen here in November 2020 posing with her female movie star of 2020 trophy at the E! People's Choice Awards — worked hard to focus on getting happier and healthier during the coronavirus pandemic, a period during which she and rapper Common fell in love and launched a new romance. "I lost 40 pounds. I've been working out and eating right and getting my little life together," she told "Extra." "I'm not gonna lie to you, my knees were hurting a lot in 2019. I was carrying a lot of things around, a lot of weight, unnecessary weight, unnecessary hurt. I had to let all that go — a lot of mental things — let that go."

On Oct. 23, 2020, Busta Rhymes posted a side-by-side image of himself on Instagram revealing a major slim-down. One of the pictures (left) was undated. The other (right) was recent. What a difference! "DON'T EVER GIVE UP ON YOURSELF!! LIFE BEGINS RIGHT NOW!!!" the rapper captioned the post. According to reports, he's lost more than 100 pounds.

"America's Got Talent" judge Simon Cowell — seen here in 2018 — revealed in May 2019 that he'd undergone a lifestyle overhaul that included switching to a vegan diet following a bad fall in 2017. He told "Extra" that as a result, he'd lost 20 pounds and was feeling "much better" overall. He looks much better too! Then, in May 2020, he revealed he'd lost even more weight — 60 pounds in total!

Simon Cowell's initial 20-pound weight loss since going vegan was evident when he hit the red carpet at the "America's Got Talent" Season 14 live show in Hollywood on Aug. 13, 2019. Simon explained to the Sun that in addition to cutting out meat, dairy and other animal products in his quest to become vegan, he also gave up wheat and sugar, as well as melon after learning he's allergic. The toughest part of being vegan? Giving up traditional pizza. "That's been really, really hard," Simon told "Extra," adding that he's so committed to his new lifestyle, he doesn't even allow himself a "cheat day." As the months went on, he slimmed down even more — keep reading to see…

During a chat with "Extra" in May 2020, Simon Cowell revealed he'd lost even more weight. "I think I have dropped, since I started this diet a year ago, 60 pounds," he said. The British music mogul also shared that he wasn't finding it hard to stick to a healthy diet and lifestyle while quarantining with girlfriend Lauren Silverman and their son, Eric, during the coronavirus pandemic. "I'm doing a bit of cooking," he said. "I'm exercising. Funny enough, more during this time as well, sticking to the diet. The only difficult thing is when Eric orders a pizza… That's the No. 1 thing I miss."

Tony-winning Broadway star Marissa Jaret Winokur — who made a name for herself as Tracy Turnblad in "Hairspray" — has long been open about her struggles with her weight. In 2012, the cervical cancer survivor publicly shared how she'd lost 60 pounds and gone from a size 14 to a size 2… only to gain much of it back again. Amidst the 2020 coronavirus pandemic, the former "Stacked" star and "Dancing With the Stars" contestant — seen here in August 2019 — revealed she's lost a significant amount of weight again. See her now…

On Sept. 14, 2020, Marissa Jaret Winokur took to Instagram to share a slideshow of before-and-after photos revealing her major slim-down during the coronavirus pandemic. "Covid scares me. I checked off all the boxes, I am HIGH RISK!" she explained in a lengthy caption. "So I started working out at home with [trainer] Keith [Anthony] via zoom classes and eating healthy to have a fighting chance." Six months later, the actress revealed, "I have lost almost 50 pounds." However, she cautioned, referencing her previous weight loss, "We have been here before. I was scared to post photos, it's really one day at a time for me when it comes to food. But I thought, 'Covid isn't over we are all sitting ducks maybe I could inspire someone ANYONE to chose to fight!' Forget how amazing this dress looks 🥰." Another bonus? "I haven't had asthma in months," she added.

"Clerks" filmmaker and star Kevin Smith, seen here in 2008, endured an embarrassing incident in 2010 where he was kicked off of a Southwest Airlines flight for being too large to fit into a seat. But he did something about it after a health scare. Keep reading to see his transformation…

By June 2015, Kevin Smith had lost 85 pounds! The actor-director-producer had begun to lose weight following the aforementioned airline incident, but he said the 2014 documentary "Fed Up" was a huge-wake up call for him to live a healthier lifestyle. "Awesome documentary, an anti-sugar documentary that completely changed my perception," he told Men's Health, adding that he grew up paying no mind to his diet. "So then I watch this documentary last year, and I was, like, 'Oh, man, um, I really don't wanna die' — and I'm already 44 years old." In February 2018, Kevin — who'd let some of the weight creep back on — had a major heart attack that almost killed him. His doctor ordered him to lose 50 pounds, and four weeks later, he was already down 26 pounds, he proudly announced on Twitter. He's since lost even more, as seen here in January 2019.

For years, former "Modern Family" star Ariel Winter's weight has fluctuated. However, after changing medications and adopting a healthier lifestyle, the young actress, seen here in 2016, underwent a major transformation…

In April 2019, Ariel Winter, who has always been candid about body image, took to Instagram to discuss the reason behind her recent weight loss. "For years I had been on anti-depressants that caused me to gain weight that I couldn't lose no matter what I did. It was always frustrating for me because I wanted to get fit and feel like the work I was doing was paying off, but it never felt that way," she began. She went on to explain how a change in medication improved her metabolism and made her drop the weight. "While I feel better mentally with the change, it's nice to work out and have your body actually respond. I want to gain a few pounds of muscle and get healthier," she added. The actress also revealed that in addition to working out, she'd also cut back on "eating a ton of cheese, bread and greasy food," which helped her feel "more energized and healthier." She's seen here at an event in Las Vegas the same month.

Kelly Clarkson's weight-loss journey has been a roller coaster. The mother of two, seen here in 2015, opened up about her experience in June 2018, telling the "Today" show that she was diagnosed with an autoimmune disease and a thyroid problem in 2006. In recent years, she read "The Plant Paradox," a book she said changed her entire eating regimen — and her figure! "It worked wonderfully for me. It's, like, 37 pounds [lost], like, that's a side effect," she said. "Here's the best part, y'all. It's not even the weight. I mean, I know the industry loves the weight gone, but for me it wasn't really the weight. For me, it was [that] I'm not on my medicine anymore. My blood work came back and I haven't been on my medicine since, like, February [2018]." Next up, see her slimmed-down look…

Kelly Clarkson showed off a slimmer figure when she performed on the "Today" show in June 2018, where she explained that she's still eating the food she loves. "Honestly, it's the same stuff you eat, I just use different ingredients," she said. "I still have, like, cake. Like, literally, I still have everything the same as I did, even, like, fried chicken, but I use, like, casoid flour, tapioca or almond flour. And I use, like, non-hormone chicken." And in 2019, Kelly seemed to be shedding even more weight. The star debuted an even slimmer frame ahead of hosting the Billboard Music Awards in May 2019 (pictured).

"Remember The Titans" actor Ethan Suplee — seen here in 2000 — has spent years slimming down and documenting all of his hard work in the gym on social media. Keep reading to see the results of Ethan's years-long slim-down…

Over the years Ethan Suplee has lost a whopping 200 pounds! He's said he got obsessively into bike riding and then slimmed down so much that he started missing out on work. From there, he found the gym. He explained his process in a 2017 interview with Entertainment Weekly, saying, "I'm not going to kill myself to be thin when nobody knows me as a thin person, and I do think it is affecting the kind of jobs I'm getting. And so I just kind of relaxed on my diet." He's seen here in late 2019.

In November 2015, Shonda Rhimes (seen here in 2011) opened up about how she lost 127 pounds that year. The impetus for the change? She couldn't get the airplane seatbelt around her waist. But she continued to slim down…

"I work really hard in every other area of my life. Why wouldn't I throw myself into being healthy and losing weight?" Shonda Rhimes told ABC News in 2015, explaining that she treated her weight loss like a job. The ABC powerhouse decided she also wanted to lose weight for her children. "I have a 3 year old and a 13 year old and a 2 year old and I wanted to be around for them, be healthy," Shonda said. It looks like she's still doing a great job: She looked super-slim on the red carpet in March 2018.

While he's been rocking a slimmer figure for years now, earlier in his career, Jimmy Kimmel was unaware of how his eating habits were impacting his overall health. In 2010, when Dr. Oz appeared on his eponymous talk show, Jimmy was called out for his eating and exercise habits. "For years I had no idea what I weighed. I finally bought a scale in 2010. I think I ordered it because I'd read on a gadget website that it had WiFi. I weighed 208," Jimmy told Men's Journal in 2015. "When you see that number, it makes you look at yourself differently."

Intermittent fasting helped Jimmy Kimmel slim down and maintain a healthy weight — specifically a method known as the 5:2 diet. "On Monday and Thursday, I eat fewer than 500 calories a day, then I eat like a pig for the other five days," he explained to Men's Journal in 2015 around the time this photo was snapped. "You 'surprise' the body, keep it guessing." According to the late night host, "It sounds hard, but you get used to it and learn you can get through it. It's helped me stay at 182 pounds. And it's made me appreciate the food that I do eat." 

This photo of Christina Aguilera was taken at the 2012 American Music Awards. Do you think you'd recognize her looking about 20 pounds lighter at the same show a year later? Keep reading to find out.

Holy smokes! Christina Aguilera debuted a much slimmer figure at the 2013 American Music Awards.

After winning a plethora of Grammys in February 2015, Sam Smith decided to radically transform their look…

In just two weeks, "Stay With Me" singer Sam Smith dropped 14 pounds thanks to nutritional therapist Amelia Freer and her book "Eat. Nourish. Glow." Sam chronicled their transformation on Instagram and continued to keep the weight off — just look at them at the 2018 Grammy Awards!

Former "The View" host Sherri Shepherd shed more than 25 pounds between March and November 2018. See her transformation…

Sherri Shepherd showed of her dramatic weight loss in this Instagram selfie she posted on Nov. 30, 2018. "Getting it in!!! Over 260 days #sugarfree … can't begin to describe how @amazing I feel," she captioned the pic. "Energy, clarity of thought and mind. Focused … patient w my son. Hearing from God a lot more clearly. Present. I've done this slowly and steadily and since March I've come down over 25lbs. This is not a fad- it's my life that is at stake. – It feels so good to feel #good." Sherri — who hit a red carpet looking slimmed down just a few weeks later (seen here) — also revealed that she'd been following a ketogenic diet and tagged her mentor, who's helped her do it the "safe and healthy way," she added.

In 2011, Ricky Gervais, the co-creator and star of the British series "The Office," underwent a major body transformation. By exercising daily, the comedian (seen here in 2009) was able to lose 22 pounds without making any changes to his diet.

For years, Ricky Gervais has kept a slim figure. The comedian, however, has since admitted that keeping the weight off hasn't always been easy. "I didn't want to give up any food or drink, so I worked out," he said on "The Tonight Show with Jimmy Fallon" in 2020. Ricky, who was 58 at the time of the interview, went on to reveal that he believes his age is making it difficult to keep up with exercising. "Because I'm old and weak, I can't work out enough to burn off the calories I take in at night." 

Kathy Bates

Celebrated actress Kathy Bates changed her lifestyle and lost 60 pounds, she revealed in 2019. See her slimmed-down look next…

Kathy Bates looked like a different woman in 2019. She told Us Weekly she lost the weight by avoiding junk food and soda and by listening to her body. "My niece told me this little secret, I guess it's no secret, it's a biological thing, that at some point when you're eating, you have this involuntary sigh and that's really your brain and your stomach communicating that you've had enough," she said. "The trick is to pay attention to that and push your plate away." The transformation took "a few years," she said, adding, "I feel like a completely different person. I can move, I can walk. I just wish I had done it years ago."

Seen here in 2015, Jonah Hill bulked up for his role in "War Dogs." A few years later, he revealed a significant slimdown…

Jonah Hill looked slim and trim at the WSJ. Magazine 2018 Innovator Awards in November 2018. A few months later, he took to social media to revealed that he was transforming his body with martial arts. "I started Brazilian Jiu Jitsu 2 months ago and try and train 4 or 5 times a week," he wrote. Initially, Jonah was hesitant to do it, citing bad memories from high school. "At 35, I try and get over the stuff that made me feel weak and insecure as a teenager. It's just wasted time and lessons you'll never learn. Trying to let go of that."

Melissa McCarthy showed off her slimmed-down figure while at the Toronto Film Festival in September 2018. The actress started an inclusive fashion line called Seven7. "I have experience dressing me as a 6, a 12 and more," she has said. "And when you go above a size 12, you don't lose your love of fashion."

John Goodman told David Letterman in 2010 that at his heaviest, he was "pushing 400" pounds. As the public has seen over the years, the actor fluctuates. "I'd lose 60 pounds every spring, and then I got too fond of the barley corn and I'd just start missing it too much," he said. "And then it would just screw everything up. I'd gain it all back and then some every year." Keep reading to see what he looks like now.

Fortunately, a knee surgery in 2014 caused by years of unhealthy living and weight gain forced John Goodman to get on the right path. The actor showed off his much thinner frame at the Golden Globes in January 2018. Just like everything else, a fit life is hard work. "It's going to be an ongoing process for the rest of my life," John has said.

Oprah Winfrey (seen here in December 2015) has struggled with her weight for years and publicly started doing Weight Watchers in late 2015 — she also purchased a stake in the company — which helped her shed pounds well into 2016 and 2017. Keep reading to see her new physique!

Oprah Winfrey has been showing off her Weight Watchers-inspired slimdown over the last few years. She looked especially trim and fit in a Versace gown at the 2018 Golden Globes.

We first met June Shannon, best known as Mama June, back in 2012 when her daughter Alana Thompson — aka Honey Boo Boo — appeared on TLC's "Toddlers and Tiaras." Her outrageous behavior landed the family a spin-off, "Here Comes Honey Boo Boo," which ran from 2012 until 2014. Since the show ended, June — who's said she once got up to 460 pounds — has been dedicated to slimming down. In 2017, she debuted her massive weight loss on her WE tv show, "Mama June: From Hot to Not," and she's kept the weight off!

June Shannon lost 300 pounds! The star underwent gastric sleeve surgery, started exercising and completely overhauled her diet. She also went through various plastic surgeries to remove more than 9 pounds of extra skin under her arms and neck and on her stomach. The reality star proudly showed off her slim physique while stopping by "Extra" in January 2018.

Back in 2012, Khloe Kardashian was struggling to stay in shape. "Looking back at pictures of myself I didn't realize at the time how unhealthy my lifestyle actually was," she explained on Instagram after she underwent a major diet and exercise overhaul…

Khloe Kardashian's weight-loss journey began in 2013. In 2016, she revealed she'd lost about 40 pounds in three years. The reality star has said that her motivation came as a result of her painful divorce from Lamar Odom and her growing desire to get her health and happiness in order, which is exactly what she did. During the last trimester of her pregnancy in 2018, Khloe confessed she couldn't wait to get back to the gym after her daughter arrived. "BEAST MODE is dying to return!! I know it won't be easy but I'm excited for the challenge," she tweeted.

"This Is Us" star Chris Sullivan is seen here in 2012. It's not known how much he weighed at the time, but he sure doesn't look like this anymore.

Chris Sullivan looked quite fit while attending the Critics' Choice Awards in January 2018. For his role as an overweight character on "This Is Us," Chris actually wears a fat suit.

Gabourey Sidibe (seen here in 2015) has made it clear she loves herself no matter what anyone else thinks. But in recent years, she decided to slim down — on her own terms.

Gabourey Sidibe showed off a much slimmer physique at the Essence Black Women in Hollywood Awards in March 2018.

When Nicole "Snooki" Polizzi was on MTV's "Jersey Shore" back in 2009, she was more worried about partying than her weight. But that has since changed!

Even after having two kids, Nicole "Snooki" Polizzi has really slimmed down post-"Jersey Shore." The reality star credits multiple workouts a week and staying away from carbs for her slim figure, seen here in March 2018.

Ed Sheeran is seen here winning a Grammy for best pop solo performance for "Thinking Out Loud" in February 2016. He's lost a lot of weight since then.

Ed Sheeran went shirtless in his 2017 "Shape of You" video after losing 50 pounds. How'd he do it? The singer-songwriter said he exercised and cut beer from his diet. And he's keeping it up! In February 2017 at the BRIT Awards, he looked just as fit.

Comedian Leslie Jones, seen here in 2012 during a stand-up performance, was told by a doctor in 2015 to lose 40 pounds.

Leslie Jones, seen here in September 2017, dropped 40 pounds by working out and running around the set of "Ghostbusters" with her heavy ghost-busting pack. She also eliminated soda and juice from her diet.

Tyler Perry (seen here in 2010) decided to take his health into his own hands and work at slimming down in 2015. The Hollywood heavyweight said that his mother was the reason he decided to take better care of himself so he set a goal weight, and by November 2015, he was well on his way.

In November 2015, Tyler Perry shared a shirtless snap on a tranquil beach, which featured his impressive abs. "I'm 18 lbs away from my goal. I hope I don't blow it this holiday season. Gonna try to stay on it. It's hard as heck to lose weight after 40, but it's so worth it," Tyler shared. He's stayed slim ever since, as seen here at a movie premiere in March 2018.

Kirstie Alley, seen here in 2013, has been known to yo-yo with her weight over the years. But she debuted a svelte frame in 2015 thanks to Jenny Craig. Keep reading to see her transformation…

Kirstie Alley revealed a 50-pound weight loss in January 2015 that she achieved on the Jenny Craig program. That weight loss stuck, as she looked just as slim on the set of "Extra" in January 2016.

Want to know the secret to "The Hangover" star Zach Galifianakis's weight loss in 2014? Keep reading to find out — and to see his slimmed-down bod.

In May 2013, Zach Galifianakis spoke about how he was starting to lose weight: "I stopped drinking and I just kind of put the weight off," he told Conan O'Brien. It definitely paid off, because years later, he's still looking great! Just check him out at the "A Wrinkle in Time" premiere in February 2018!

When Adrienne Bailon met her future husband, they bonded over food, which had them putting on some pounds. She was determined to lose a lot of that weight by the time her Paris nuptials rolled around.

Adrienne Bailon looked svelte on her wedding day on Nov. 11, 2016, after losing 22 pounds. Her husband, Israel Houghton, lost 25 pounds before their big day. "I love the way my clothes are fitting so much that I don't want to stop," she told People magazine. "I want this to become a lifestyle. I'm enjoying working out. I enjoy the way it makes me feel." She's kept the weight off. Adrienne looked svelte at the NAACP Image Awards in January 2018.

Do you want to know how former "How I Met Your Mother" star Jason Segel shed more than 30 pounds a few years back? Then keep clickin'!

In 2013, Jason Segel told Us Weekly: "I've just been living healthy, exercising, eating right — no more midnight pizzas." He's kept the weight off — just take a look at him in 2020!

Timothy Spall, seen here in 2014, has been tight-lipped about where he was at his heaviest. But he looks nothing like this now.

Timothy Spall was noticeably slimmer when he attended the 73rd Venice Film Festival on Sept. 7, 2016. He hasn't detailed the type of lifestyle changes that he made, but he did tell a news outlet that he cut down on alcohol.

When Jerry Ferrara joined the cast of "Entourage," he had a bulkier frame. By the time the movie adaptation of the HBO series hit theaters on June 3, 2015, he had lost 40 pounds.

So what motivated Jerry Ferrara's weight loss? He revealed that he was required to take a physical during Season 6 on "Entourage" and, though he passed