Hollywood actors all have their own processes for preparing for roles and sometimes, that process includes physically transforming for a role as well as emotionally.
Some actors like Christian Bale, Matthew McConaughey and Anne Hathaway have had to lose up to 50lbs through extreme diets and fasting regiments to play sickly characters.
Others like Jared Leto and Charlize Theron have gone in the opposite extreme and gained weight by overeating to play real-life figures.
Kumail Nanjiani, Chris Hemsworth and Jonah Hill have used roles as a reason to optimize their nutrition and commit to a workout regiment in order to get in the best shape of their lives.
Natalie Portman is one of these stars. The Thor actress recently reflected on how being asked to get ‘bigger’ for her role as Jane Foster was a ‘career highlight’ after being told she had to lose weight for other roles.
Whether it was the safest or most ethical thing to do, these actors have gone through extreme weight transformations to embody roles on the big screen.
Double trouble: Natalie Portman bulked up for Thor – years after shedding 20lbs to portray a ballerina in Black Swan
Portman (pictured left in 2019) got to bulk up for playing Jane Foster in Thor like in the sequel Thor: Love and Thunder (pictured right) and called it a ‘career highlight’
Portman has had to make drastic weight transformations on both ends of the spectrum during her Hollywood career.
For the 2010 horror thriller Black Swan, Portman notoriously lost 20lbs. At the time, the actress told Daily Mail that she first started training to get her body in shape for the role a year before filming started.
At that point, she trained for two hours a day. Six months before filming, it was ramped up to five hours a day and eventually, two months before filming, she trained eight hours a day.
‘The discipline was good for the part—it hurt a lot; your body is in constant pain,’ the actress, who was 29 years old at the time, explained.
‘There were some nights that I thought I literally was going to die,’ she told EW. ‘It was the first time I understood how you could get so wrapped up in a role that it could sort of take you down.’
However, not only did the actress lose weight but she almost lost herself in the process.
‘It was more difficult than anything I’ve ever experienced before. I like to go home and be myself but with this one I didn’t get the chance. It didn’t leave me,’ she told Daily Mail in a 2011 interview.
‘I was barely eating, I was working 16 hours a day. I was almost method acting without intending to.’
Portman (pictured left in 2003) ‘thought she was going to die’ at some points while filming Black Swan (pictured right in 2010) after losing 20lbs
A year after Black Swan wowed audiences, Portman starred in Thor as Jane Foster and was tasked with the exact opposite goal.
‘On Black Swan, I was asked to get as small as possible,’ she told Variety in 2022 ahead of the premiere of Thor: Love and Thunder. ‘Here, I was asked to get as big as possible. That’s an amazing challenge – and also a state of mind as a woman.’
While appearing on ITV, she claimed her experience training was ‘wonderful’ this time around and that she had never ‘been tasked in my lifetime to get as big as possible.’
She told Vanity Fair she gained about a pound of muscle during her four months of training – meaning she gained about four pounds in muscle for the role.
Portman played Jane in Thor (2011), Thor: The Dark World (2013) and Thor: Love and Thunder (2022).
What a hero! Chris Hemsworth also bulked up big-time for Thor
Hemsworth did not work out much before Thor (pictured left in 2005) but gained 20lbs of muscle for the Thor films (pictured right)
Hemsworth also had to go through quite the transformation as the star of MCU’s Thor movies.
The 38-year-old actor gained 20lbs of muscle for the first Thor film in 2011. His main approach to bulking up was working on his diet.
‘Chris’s goal while filming was to eat 4000-4500 calories a day,’ his trainer Luke Zocchi told Centr. The actor achieved this by having six meals a day – eating every two to three hours.
‘I feel as if I’ve been busy, but all I’ve been doing is eating all day,’ Hemsworth told Men’s Health at the time. “Eating when you’re not hungry and taking in that amount of food is exhausting.”
He also started lifting weights, which is something the actor hadn’t done much of prior to his Thor days.
The MCU actor followed a special protocol for when he’d have to film shirtless scenes.
‘We start with three liters and everyday increase by one liter, and then by the end, he drinks seven liters of water,’ Zocchi told the fitness app. ‘Then around lunchtime before the scene, we cut water completely.’
He was sure to add: ‘This is by no means a healthy thing to do, and I wouldn’t recommend that anyone else do this.’
Mila Kunis thought she looked ‘gross’ after dropping down to 95lbs for Black Swan
Kunis lost 20lbs for the 2010 film Black Swan (pictured righy) but claimed she had ‘no shape’ compared to how she looked before the film (pictured left in 2009)
Like Portman, Kunis had to drop 20lbs to play a ballerina in the 2010 hit Black Swan. Similarly to her friend and costar, she described the process as grueling.
‘I didn’t starve myself,’ the 38-year-old actress said while reflecting on the experience on Howard Stern’s SiriusXM Show in 2016. ‘I did do it in the healthiest way possible. I don’t recommend anybody ever doing it.’
‘And I’ll tell you this — I’m not promoting this at all — but I used to be a smoker, and so I smoked a lot of cigarettes and I ate a limited amount of calories.’
‘Twelve-hundred calories and I smoked,’ she reiterates about her weight-loss methods. ‘I don’t advocate this at all. It was awful.’
The actress ended up weighing 95lbs while she was filming Black Swan – but she didn’t enjoy being that skinny.
‘I could see why this industry is so f–ked up, because at 95 pounds, I would literally look at myself in the mirror and I was like, “Oh my God!” I had no shape, no boobs, no ass…All you saw was bone. I was like, “This looks gross,”‘ she told E! News after the film came out in 2010.
She also joked that while it took her five months to lose the weight, it took her ‘just five days to gain it all back.’
Chris Pratt lost 60lbs in just six months for The Guardians of the Galaxy – after tipping the scales at close to 300lbs in Parks and Recreation
Pratt (pictured left in 2013) dropped 60lbs for 2014 film The Guardians of the Galaxy (pictured right)
Pratt has undergone one of the most notable Hollywood weight transformations. The 43-year-old actor admitted that there were a number of factors that contributed to his weight while he was filming Parks and Recreation from 2009 to 2015.
The first of those was his relationship status at the time.
‘I put on weight because I’d fallen in love with a woman [actress Anna Faris] who loved to feed her man. We were drinking a lot of wine and having fun,’ he told Men’s Health UK in 2015.
He also thought it would help him channel Andy, his lovable character from Parks and Recreation.
‘I wanted to get fatter for the role [in Parks and Recreation]. I announced it to the whole cast, and then it became a bit of a game: how fat can I get and how fast.’
Pratt (pictured left in 2003) said getting heavier for Parks and Recreation became a game and gained up to 300lbs (pictured right)
However, he admitted that he took his mission to gain weight too far and ended up weighing almost 300lbs at his max.
‘I would eat four burgers at every read. I became really fat and got up to almost 300lb. I had real health issues that were affecting me in a major way. It’s bad for your heart, your skin, your system, your spirit.’
He then dropped a whopping 60lbs in order to play the superhero Star-lord in Guardians of the Galaxy.
He told Men’s Health Journal that in order to drop the weight, he did ‘three or four hours a day of just consistent, ass-kicking hard work.’
That hard work included P90X, running, swimming, boxing, kickboxing, and even a triathlon.
David Harbour lost 80lbs between Stranger Things seasons three and four
Harbour weighed 270lbs in Stranger Things season three but was down to 190lbs by the time season four started filming
Stranger Things’ Hopper went through a major transformation during season four. While detained in a Russian prison, he was tortured and starved and actor David Harbour committed to embodying that look.
Harbour dropped a whopping 80lbs between Stranger Things seasons three and four.
Speaking on Tuesday’s BBC Breakfast he explained his process: ‘It’s not easy, it’s a lot of not eating when you lose that much weight, and being hungry.’
He then jokingly added: ‘That’s the secret, if you’re curious about the diet secret, it’s just not eating food.’
‘You know at the end of season three I was about 270 pounds and then when we came into this season I was 190.’
Even though the 47-year-old actor hit his goal, he admitted it affected his performance.
He told Screen Rant that he was ‘hungry a lot of the shoot’ and felt that ‘it’s not very good for me, mentally and nutritionally.’
Christian Bale covered both extremes, losing 62lbs for The Machinist and gaining 43lbs for American Hustle
Bale (pictured left in 2003) lost 62lbs for The Machinist in 2004
Over the course of his career, Bale has gained a reputation for the drastic transformations he endured for the roles he has played.
His arguably most shocking transformation was for The Machinist which hit theaters in 2004. His character Trevor suffered from extreme insomnia which has taken a toll on him physically and mentally – and Bale undeniably committed to the physical part.
For The Machinist, he was on a diet of black coffee, one apple and a tin of tuna per day and lost 62lbs in total.
His extreme weight loss methods aren’t exactly backed by health experts.
‘This is less than 200 calories per day, so it’s not healthy at all,’ health expert Daniel O’Shaughnessy told Esquire UK. ‘An extreme diet like this will play havoc with your metabolism and cause a lot of stress on the body.’
He completely flipped the script and gained a ton of weight nearly ten years later for the 2013 film American Hustle. Bale played Irving Rosenfield – inspired by real-life con artist Mel Weinberg – wanted to truly embody the role.
Bale (pictured left in 2012) gained 43lbs for American Hustle (pictured right)
Once again, Bale drastically changed his diet but this time it was to gain weight – specifically, 43lbs.
‘I ate lots of doughnuts, a whole lot of cheeseburgers and whatever I could get my hands on. I literally ate anything that came my way,’ he told People after filming wrapped. ‘I literally ate anything that came my way. I was about 185[lbs] and went up to 228.’
Even though Bale has made some wild transformations over the years, the 48-year-old is done pushing his body to the extreme in either direction.
‘I’ve become a little bit more boring now, because I’m older and I feel like if I keep doing what I’ve done in the past I’m going to die. So, I’d prefer not to die,’ Bale told E! News (via Men’s Health Journal) in 2019.
Matthew McConaughey lost 50lbs to play an AIDS patient in Dallas Buyers Club
McConaughey (pictured left in 2011) lost 50lbs for his role in Dallas Buyers Club in 2013 (pictured right)
McConaughey dropped some serious weight for Dallas Buyers Club (2013.) The actor played a Texan electrician who is stunned when he learns that he has AIDS.
The actor was committed to giving a truthful portrayal of the role and felt that losing 50lbs was the only way.
‘It was my responsibility,’ he said on the Joe Rogan Experience in 2020. ‘If I looked how I look now and played Ron Woodroof from Dallas Buyers Club, you are out of the movie the first frame.’
He added: ‘I did not torture myself. I was militant. The hardest part was making the damn choice.’
The actor followed a very specific diet of 5 ounces of fish for lunch and dinner, small amounts of vegetables with each meal, and egg whites for breakfast – as well as ‘as much wine as I wanted to drink.’
He would also treat himself to an extremely unique dessert.
‘I found tapioca pudding, and I found the tiniest little antique spoon in New Orleans, a little-bitty sugar spoon, and I would eat it with that so it would last longer,’ he shared.
The actor bulked up again for the Magic Mike sequel.
Charlize Theron gained 30lbs for Monster – then upped the ante by piling on 50lbs for Tully
Theron (pictured left in 2002) gained 30lbs for Monster (pictured left) to portray Aileen Wuornos
Theron took incredible weight feats for her roles in Monster (2003) and Tully (2018).
In Monster, Theron played real-life prostitute and serial killer Aileen Wuornos. Theron felt it was important to give an accurate representation of Aileen considering she was playing a real-life figure.
‘It wasn’t about getting fat. Aileen wasn’t fat,’ Theron said in an interview via The Wrap. ‘Aileen carried scars on her body from her lifestyle, and if I’d gone to make this movie with my body — physically I’m very athletic — I don’t know that I would have felt the things Aileen felt with her body.’
‘It was about getting to a place where I felt closer to how Aileen was living,’ she continued.
She took on the task of gaining weight once again for Tully – except this time gained an extra 20lbs.
‘I gained close to 50 pounds for [Tully],’ Theron told ET. ‘I just I wanted to feel what this woman felt, and I think that was a way for me to get closer to her and get into that mindset.’
She added: ‘You know, it was a huge surprise to me. I got hit in the face pretty hard with depression. Yeah, for the first time in my life I was eating so much processed foods and I drank way too much sugar. I was not that fun to be around on this film.’
Theron gained 50lbs for her role in Tully (pictured left) and was initially nervous she wouldn’t be able to drop the weight but managed to (pictured right in 2020)
Theron struggled with the process, admitting gaining all that weight became a challenge after the first month.
‘The first three weeks are always fun because you’re just like a kid in a candy store. So it was fun to go and have breakfast at In-N-Out and have two milkshakes,’ she explained.
She added: ‘And then after three weeks, it’s not fun anymore. Like, all of a sudden you’re just done eating that amount and then it becomes a job. I remember having to set my alarm in the middle of the night in order to just maintain [the weight].’
The actress managed to drop the weight after both films – although she admitted that she struggled more the second time around.
‘I was worried. I was like, this is taking a really long time,’ she said. ‘Because on Monster I just didn’t snack for five days and I was fine.’
‘You know your body at 27 is a little different than your body at 43, and my doctor made sure to make me very aware of that. Like, you are 42, calm down, you’re not dying, all good.’
Jonah Hill piled on 40lbs for War Dogs and dropped it all (and then some) for Maniac
Hill (pictured left in 2012) gained 40lbs for the 2016 film War Dogs to play real-life arms dealer Efraim Diveroli
While Hill has gained weight for roles over the years for a number of roles including 21 Jump Street, he took it to the next level when he gained 40lbs to play real-life arms dealer Efraim Diveroli in War Dogs (2016).
However, he shocked fans when he dropped all that weight and even more for his role as a patient with schizophrenia in the Netflix miniseries Maniac (2018).
When Hill first decided to lose weight, he turned to another famous friend for advice.
‘I wanted to get in better shape, so I called Channing Tatum and said, “Hey, if I ate less and go to a trainer, will I get in better shape?”‘ Hill told Jimmy Fallon during an appearance on The Tonight Show in 2016.
‘[He said] ‘Yes, you dumb motherf–er, of course you will.’ It’s the simplest thing in the entire world.’
‘It was just mostly diet,’ he told ABC News (via Mirror) of his weight loss journey.
Hill (pictured left in 2016) got advice from his friend Channing Tatum when he wanted to drop weight for the 2018 miniseries Maniac (pictured right)
‘I wish there was some crazy thing that I did, like a pill or a genie or something, but I went to see a nutritionist, and he told me what to eat to change my habits and stuff.’
The comedian also claims that Japanese food was ‘very friendly’ to him.
He told Kidd Kraddick that as far exercise went, he ‘started physically running instead of emotionally running.’ He also took up boxing.
In recent times, Hill has spoken out about how he doesn’t care to hear any commentary on his weight from fans – positive or not.
The penned a heartfelt message on Instagram, stating, ‘I know you mean well but I kindly ask that you not comment on my body good or bad I want to politely let you know it’s not helpful and doesn’t feel good. Much respect.’
Jared Leto’s extreme weight gain for Chapter 27 caused him to develop gout and require a wheelchair to get around
Leto (pictured left in 2004) gained 67lbs for the 2007 film Chapter 27 (pictured left) and ended up developing gout
Leto has lost weight for a number of roles in films like Requiem For a Dream and Dallas Buyers Club and took his health to dangerous places – including to fasting so often that he began to hallucinate.
However, the riskiest transformation he made was when he embodied John Lennon’s killer, Mark David Chapman in the 2007 film Chapter 27 by gaining a whopping 67lbs.
‘Really, it’s a stupid thing to do,’ he told The Guardian his weight gain for Chapter 27. ‘I got gout, and my cholesterol went up so fast in such a short time that my doctors wanted to put me on Lipitor, which is for much, much older people.’
In fact, he suffered so much that ended up needing a wheel chair.
‘I had a definite problem with my feet. Towards the end of the shoot, one of the glaring issues was the pain I had with my feet,’ he told Digital Spy.
‘I couldn’t walk for long distances; I had a wheelchair because it was so painful. My body was in shock from the amount of weight I gained.’
Once he was done filming, he quickly lost the weight by returning to one of his true and tried practices – fasting.
‘”I’ve been fasting ever since. I’ve been doing this very strange, like, lemon and cayenne pepper and water fast. I didn’t eat any food for 10 days straight; I think I lost 20 pounds that first 10 days.” he told Jimmy Kimmel.
Renee Zellweger gained 30lbs over the course of the Bridget Jones franchise – but insisted on wearing a fat suit for The Thing About Pam
Zellweger (pictured left in 1998) gained weight for Bridget Jones’ Diary in 2001 (pictured right)
Zellweger gained weight to play the unconventional romantic comedy heroine Bridget Jones in Bridget Jones’ Diary (2001).
‘I’d have an omelet with cheese and sauce for breakfast with a fatty yogurt and then a fruit salad with a topping and juice and coffee and cream and a bagel with butter and a few hours later a chocolate shake with weight-gain powder in it,’ Zellweger told The New York Times in 2000.
‘It was like, do the research, learn your lines, eat the shake. It was all part of the job.’
The actress lost all of the weight and gained it back for the 2004 sequel. In total, she gained 30lbs between the two films.
However, she grew weary of the process of gaining weight so quickly after hearing experts weigh in on the documentary Super Size me, in which a man sees how much weight he would gain by eating large quantities of McDonalds for a month.
‘I had a panic attack with all the specialists talking about how bad this is for you long-term, putting on that much weight in short periods of time,’ she revealed in an interview in 2007.
Fortunately, Zellweger and the writers were both on the same page by the time the third film came out in 2016.
Zellweger shared that she only gained ‘a few pounds’ for the third time around – on top of wearing an enhanced baby bump and breasts.
She also recently defended Bridget’s average weight of 136lbs – a topic that has been debated by body positivity advocates over the years.
‘Bridget is a perfectly normal weight and I’ve never understood why it matters so much. No male actor would get such scrutiny if he did the same thing for a role,’ she told British Vogue in 2016.
Zellweger (pictured left in 2021) wore a fat suit and prosthetics to play Pam Krupp in The Thing About Pam in 2022 (pictured right)
Perhaps it was her anxieties from gaining weight for the first two Bridget Jones movies that caused her to go with a fat suit and prosthetics for The Thing About Pam (2022).
‘It was pretty much head to toe. It was prosthetics, it was a [padded] suit, it was the choice of clothing, it was the briskness in her step-step-step, her gait,’ Zellweger told Vanity Fair about her transformation into real-life figure Pam Hupp.
‘All of those things were really important because all those bits and pieces are what construct the person that we project our own conclusions and presumptions onto.’
Although the actress has received plenty of backlash for her decision, she continues to defend it.
‘The idea is to be accurate, the idea is accuracy,’ the Bridget Jones’s Diary star told ET.
‘I think, especially in the case of telling this story, it was really important to as closely resemble Pam Hupp as we possibly could, because she seems so familiar, she seems like someone that we recognize, and we know.’
‘In order for you to better understand how possible it might be that people would project onto her who they are sure that she might be or what kind of person she might, it just seemed really important that we got as close to that as we could,’ she continued.
Kumail Nanjiani broke the internet with his transformation for Eternals
Najiani (pictured left in 2012) was honest about how he got in shape for Eternals (pictured right)
Nanjiani made headlines when he got shredded for his role of Kingo in MCU’s Eternals.
The 44-year-old actor wowed fans when he showed off his new body on Instagram. However, he made sure to note that he wouldn’t have been able to do it without the resources he had access to as a celebrity.
‘I would not have been able to do this if I didn’t have a full year with the best trainers and nutritionists paid for by the biggest studio in the world,’ Nanjiani wrote in the photo caption.
‘I’m glad I look like this, but I also understand why I never did before. It would have been impossible without these resources and time.’
Nanjiani’s trainer Grant Roberts told THR that the Marvel star worked out, on average, four to five days per week, including some two-a-days.
On his own Instagram account, he maintained that the actor did it ‘the way anyone can’ – with ‘optimum nutrition and training.’
‘It does not require starving yourself or working out for hours upon hours every day but it does take discipline and the ability to push yourself and continue to find new limits,’ he wrote in the post’s caption.
Anne Hathaway got sick losing weight to play the impoverished Fantine in Les Miserables
Hathaway (pictured left in 2011) lost 25lbs for Les Mis in 2012 (pictured right) in order to look ‘near death’
Hathaway dropped 25lbs to play the famished prostitute Fantine in the 2012 movie musical Les Miserables. The actress credits a strict diet of dried oatmeal paste for helping her drop the weight.
‘I had to be obsessive about it – the idea was to look near death,’ she told Vogue in 2012.
Many people expressed concern over the extreme weight loss, and Hathaway ultimately agreed that it wasn’t the healthiest thing for her.
‘That weight loss was not a long-term good thing for my health, and it took a really long time to come back from it,’ she told the outlet. ‘And I was still really sick because of it.’
She dug deeper into the process years later and admitted that it was a tough time for her.
‘I’d lost an unhealthy amount of weight in two weeks,’ Hathaway told PEOPLE upon reflecting on Les Mis in 2019.
‘I didn’t know anything about nutrition. I taxed my body, and my brain bore the brunt of it for a while. I just felt very anxious and very lost at that time.’
Jake Gyllenhaal gained 28lbs of muscle for Southpaw
Gyllenhaal (pictured left in 2012) gained 28lbs of muscle for the 2015 film Southpaw (pictured right) through a rigorous workout regimen
Gyllenhaal has proven multiple times that he’s willing to transform his body for a role. He got ripped for Prince of Persia (2010) and slimmed down again to get to a jaunt state in Nightcrawler (2014).
However, he had to undergo his most drastic transformation of all time immediately after for the 2015 film Southpaw.
The actor gained a whopping 28lbs of muscle in order to play boxer Billy ‘The Great’ Hope.
‘Honestly, I just trained like a boxer for five months,’ he told Bodybuilder.com of his process for the film.
‘We shot the fights in the first two weeks of the movie, so I trained basically for five months up until those fights—we shot four fights in a row over roughly two weeks.’
‘But I basically trained how a professional boxer would train,’ he continued.
That regiment consisted of 1000 sit-ups, run eight miles and a tough training routine of skipping, boxing and weight training.
He also paid close attention to what he ate.
‘Nutritionally, it was 6-7 meals a day, eating every three hours or so—often to both fuel for my next session and to get my energy back up from the previous session,’ he explained.
‘My diet would consist of lots of eggs, chicken, fish, bananas, apples, almonds, cacao beans, raisins, goji berries, rye bread, pasta, couscous and potatoes, and lots of steamed vegetables and salad: avocado, tomatoes, broccoli, and other dark-green leaves.’
‘Nothing was fried, and everything was as natural as possible. I would drink plenty of water throughout the day, as well.’