The controversy surrounding Kim Kardashian's weight loss in order to wear Marilyn Monroe's gown to the Met Gala has once again ignited the extreme diet and exercise media debate. Some have labeled her a bad example to young women, promoting taking extreme measures to fit a garment. Others have pointed out that actors have been using this practice for decades and received no-such critique.

Related:11 Best Fashion Industry Documentaries In Honor of the Met Gala

Some actors have built careers on their ability to contort themselves to fit any role. From liquid diets to four-hour workouts, some craft their perception of the 'perfect' body for the character. Then there are the mentally driven 'Method' actors; those who pride themselves on getting into the mind of a fictitious person and living as them for an extended period of time, in order to flesh out their reality. Either way, it's clear these actors are very dedicated to their craft.

Lily James

Lily James on red carpet and as Pamela Anderson in Pam and Tommy TV Show on Disney+

Taking on an icon, especially one as bodacious as Pamela Anderson, would be a huge task for even a Doppelgänger to accomplish. When the brunette, demure and British Lily James was announced as the actress to take on the titular role in Pam & Tommy, there were skeptics. However, once on-set images leaked of James in full Anderson mode, jaws dropped.

Related: Where Does 'Pam & Tommy' Rank Against Lily James' Best Roles?

As Ms Anderson is for her figure, James worked with personal trainer Matt Bevan for four months, virtually and from home (due to Covid-19), to achieve her lean and toned Baywatch look. Prosthetics were used to give James not only Anderson's ample chest but her face, too. For four hours each morning, James underwent the application of two prosthetic facial pieces, a wig, nails, and signature 90s makeup. On top of this, she had a constantly topped-up fake tan and admitted that she and co-star Sebastian Stan would scream into pillows to give their voices a huskier tone.

Watch Pam & Tommy on Hulu

Jonah Hill

Jonah Hill in Netflix TV Show Maniac and War Dogs movie

After years of struggling with his self-image, and gaining substantial weight to play arms dealer Efraim Diveroli in War Dogs, actor Jonah Hill sought the advice of friend and Jump Street co-star Channing Tatum. Tatum, who is no stranger to getting in shape, told Hill that it's the "easiest thing in the world", meaning that a well-balanced diet and frequent exercise will inevitably show results.

Related: Essential Jonah Hill Performances, From 'Moneyball' to 'Superbad'

Hill's slim appearance in the Netflix series Maniac was far less talked about than his powerful performance. These days he prefers not to disclose the details of his lifestyle and directs more focus on the importance of self-love. Centered on this theme, Hill created a Zine titled Inner Child which he describes as a companion piece to Mid90s, a film he wrote and directed in 2018.

Watch Mid90s on Fubo

Renée Zellweger

Renee Zellweger in The Thing About Pam TV Show, Chicago and Bridget Jones Diary Movies

An actress who has experienced her fair share of weight speculation is Renée Zellweger. A staple in many 90s classics, she shared the screen with Tom Cruise, Jim Carey and Liv Tyler, but it was starring as Bridget Jones in 2001 that made her a household name. Unfortunately, the early 2000s press were more inclined to focus on Zellweger's weight than her talent. As her next film, Chicago, swept the 2002 award season, it was co-star Catherine Zeta-Jones who took the trophies, and Zellwegger who copped the negativity for her 'boney' frame.

Related: Essential Renee Zellweger Performances

In a brilliantly defiant move, Zellweger chose not to gain any weight when she reprised her role in Bridget Jones Baby in 2016. The reason behind this choice was to "show that Bridget had achieved her ideal weight, but... it didn’t mean her life was perfect". In her latest role, The Thing About Pam, Zellweger donned a 'fat suit' and prosthetics to resemble convicted killer Pam Hupp as closely as possible.

Watch The Thing About Pam on Hulu

Chris Pratt

Chris Pratt in Parks and Recreation TV Show and in Guardians of the Galaxy Marvel movie on Disney+

Long before his blockbuster debut, Chris Pratt was just a goofy guy on Parks and Recreation. The actor was more well-known for his relationship with fan-favorite and Scary Movie alumni Anna Faris than his acting capabilities, but that soon changed when Marvel came knocking.

The role of Peter Quill in Guardians of the Galaxy gave Pratt his big break and launched him to leading-man status. The actor undertook a grueling work-out regime with former marine sniper and ex-Navy SEAL Duffy Gaver, on top of cutting out all junk food and upping his overall intake. In five months he achieved what fans dubbed a shocking transformation, and he has held on to his physique and popularity for now, despite a few controversies.

Watch Guardians of the Galaxy on Disney+

Demi Moore

Demi Moore in GI Jane and General Hospital

Formative 80s Brat Pack member Demi Moore had been well and truly typecast for her beauty. Despite a few roles outside this expectation with little note, it wasn't until 1997 and Ridley Scott's G.I. Jane that Moore broke the mold. Although, it did earn her a Razzie for Worst Actress.

Prior to filming, Scott had his stars complete a Navy SEAL Bootcamp. As revealed in her memoir Inside Out, Moore vomited the first morning and had blisters come midday, but despite being given the option of opting out, she taped herself up and pressed on. Her determination, also evident in Moore shaving her head on set, set her apart as an actress. Unfortunately, G.I. Jane was flooded with bad reviews, and her career stalled as a consequence. If only they'd been allowed to keep the original ending, which tested a lot better with audiences.

Watch G.I. Jane on Fubo

Jared Leto

Jared Leto in Chapter 27, Suicide Squad and Dallas Buyers Club

The enigma that is Jared Leto has played quite a variety of roles with varying levels of success. From his Oscar-winning performance as Rayon in Dallas Buyers Club to his universally panned turn as DC's Joker in 2016's Suicide Squad, he is a testament to the fact that you can't win 'em all, no matter how hard you try.

Related:From ‘Dallas Buyers Club’ to ‘Chapter 27’: Jared Leto’s Transformative Performances

The Method actor's antics have often caused a stir with costars and garnered him some heavy criticism from both fans and colleagues. Actor Will Poulter has spoken against Method acting, stating it "shouldn't be used as an excuse for inappropriate behavior". We wonder if sending Margot Robbie a rat would be deemed inappropriate.

Watch Suicide Squad on HBOMax

Jessica Chastain

Jessica Chastain as Tammy Faye Messner in The Eyes of Tammy Faye

For her role as the titular TV Evangelist in The Eyes of Tammy Faye, Jessica Chastain took home the Best Actress Academy Award. When you see her incredible transformation, it's not hard to see why. Set during the 1970s, the heyday of televangelists, this biopic was years in the making, as was Chastain's careful character study.

Related: 9 Best Jessica Chastain Performances, From 'The Eyes of Tammy Faye' to 'The Zookeeper's Wife'

Each day of filming, Chastain had facial prosthetics applied to widen her cheeks and fill in her dimple. Next, she'd wear a wig under her wig to mimic Tammy's natural hair. Each piece of clothing was carefully designed to exude the power and drama of the real woman, so naturally, they all contained massive shoulder pads. Finally, the actual makeup brands Tammy wore were sourced and carefully applied to Chastain for the most authentic appearance possible. Along with her impeccable mirroring of minor physical movements and vocal emphasis, Chastain truly earned her award.

Watch The Eyes of Tammy Faye on HBOMax

Charlize Theron

Charlize Theron in Mad Max Fury Road, Modelling, and in Monster as Ailene Wuornos

South African actress Charlize Theron is another unafraid to shed herself for a part. From her appearances as America's first female serial killer Aileen Wuornos in Monster (2003) to Imperator Furiosa in Mad Max: Fury Road (2015), Theron has proven she is willing to get gritty in her films and her performances are consistently strong. Not to mention, she broke Tom Hardy's nose.

Theron shaved her head for the role of Furiosa, and gained weight to closer resemble Wuornos. Monster director Patty Jenkin's said her main stipulation for her lead actress was that they would allow an up-close shot of their runny nose. After seeing Theron in The Devil's Advocate (1997), she knew she would be perfect for the part. The film earned Theron her first Academy Award, which she was awarded on what would have been Wuornos' birthday.

Watch Monster on Fubo

Christian Bale

Christian Bale in the Machinist, Batman Begins and Vice

Another actor well known for the diversity of his roles is Christian Bale. The British Thespian may be best known for his turn as Christopher Nolan's Batman in The Dark Knight trilogy, but there was a time when his drastic acting choices were making headlines for all the wrong reasons.

Fans were concerned when a gaunt and ill-appearing Bale dropped 60+ pounds for The Machinist (2004). Regardless of the quality of the film, no one could get over Bale's drastic measures, which included living off a tin of tuna and an apple a day, and taking up smoking. Somehow, Bale was able to return to a healthy weight and even gained considerable muscle for his role as Bruce Wayne in Batman Begins (2005), just one year later. In 2018, he undertook yet another drastic change for Dick Cheney in Vice by putting on 40 pounds, but this time with the help of a nutritionist.

Watch Vice on Hulu

Dishonorable mention: Zoe Saldana

Zoe Saldana as Nina Simone in Nina biopic and in Avatar

The Avatar (2009) star really missed the mark when she took the role of legendary activist and artist Nina Simone in Nina (2016). While Miss Simone had requested an actress like Whoopi Goldberg to play her, should a biopic be made, studios made the unwise decision to cast Afro-Latina Saldana as the singer. Matters were made worse when it became clear the studio would be darkening her skin for the film and giving her a prosthetic nose.

Related: Musical Biopics That Nailed It (and That Went Astray)

Initially, Saldana fought back against criticism of her casting, feeling invalidated as a black woman for not being deemed 'black enough' for the part. In time, however, she began to understand the inherent pain of Colorism and regretted her role in perpetuating it. In her apology, she stated Simone "should be honored to the most specific detail" and she should have fought for another black actress to take the role.

Watch Avatar on Disney+

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