How extreme can an actor go to transform their body for their roles? Ask Jared Leto.

The veteran actor has been through multiple weight gain and weight loss sessions since starting his career back in early 1990.

The most apparent weight loss he had was for his role of Harry Goldfarb in the 2000 movie Requiem for a Dream.

To portray a drug addict, Leto hanged out with real addicts on the streets of Brooklyn and stopped eating. While the method helped him lose 25 whopping pounds, it came with a price. 

"I was in a constant state of hunger. I started fainting when I was on the set," Leto recounted during an interview with The Independent (reported by Elle).

He even suffered from liver damage and bone marrow loss by 400 points. And that wasn't all. He hallucinated and fainted at the set.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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"It was a painful, dark place, but it was rewarding," the 49-year-old admitted in the interview.

He revealed that the most hazardous aftereffect of the sudden weight loss was that he struggled to eat normally.

Jared Leto Struggled for Weight Gain

Over the years, Leto has gained significant weight for many of his movie roles. He packed on the pounds for his highly applauded role of Joker in Suicide Squad and Mark Chapman in Chapter 27. 

But the weight gain was admittedly more challenging than weight loss. "I'm terrible at eating a lot," he told Billboard magazine in 2015. 

The Suicide Squad actor added he was trying to gain weight by eating every couple of hours but struggled to eat. 

Sudden Weight Gain Put Him in a Wheelchair

Despite all odds, Leto gained 65 pounds for his role in Chapter 27, where he portrayed the real-life disturbed Beatles fan who assassinated John Lennon in 1980. 

Leto became unrecognizable with his unhealthy vegan diet that included pizza, pasta gut-buster, melted pints of Häagen-Dazs ice cream mixed with olive oil and soy sauce for maximum bloat.

While the massive weight gain earned Leto applauds, it also brought him health challenges, including gout, a common yet severe form of arthritis.

In addition, the sudden increase in his weight affected his feet. So much so, Leto had to use a wheelchair. 

"My body was in shock from the amount of weight I gained," he disclosed during an interview with Digitalspy in 2009.

The Louisiana native also shared that it took him almost a year to get back to a place that felt semi-normal. 

He had used the Master Cleanse method to lose pounds. Ergo, he didn't eat solid food for the first ten days and lost 20 pounds.

After that, he continued fasting with varying lemon, cayenne pepper, and water techniques. 

"Really, it's a stupid thing to do," he later told The Guardian in 2014. He even mentioned how his doctors were thinking of putting him on Lipitor because of his cholesterol rise.

Thankfully, that didn't happen, and Leto got back to his average weight.