It's Always Sunny is one of the most successful shows of all time, and it achieved this by being consistently among the best offerings on TV. The show has amazing and terrible characters, episodes that are totally insane, and a cast that has made bank thanks to the show's success.

Rob McElhenney has undergone some dramatic physical transformations on the show, and he's done so by getting on some wild diets. His most recent transformation saw him get shredded, and people want to know if he did it naturally or with some synthetic help. We have some key details below!

Rob McElhenney Is Brilliant On 'It's Always Sunny'

Ever since the show's debut back in 2005, Rob McElhenney has been brilliant as Mac on It's Always Sunny in Philadelphia. As the creator and developer of the show, McElhenney's brilliance has been shining on the small screen for years now, and the show continues to churn out high-quality stuff.

As one of the most successful shows of all time, there are few series around that compare to It's Always Sunny. No, it doesn't have the same runaway popularity as shows like The Office, but it's lasted longer and hasn't tanked in quality.

Thankfully, McElhenney wants to keep the show going.

"I’ll do it forever. If people keep watching it and we keep having fun, why would we ever stop? It’s my dream job. I never understand why people leave shows. I don’t. I never understand that," he said.

McElhenney is fantastic on the show, and he's transformed himself physically multiple times all in the name of comedy.

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Rob McElhenney Put On 60-Pounds

In what came as a complete and total shock to fans of the show, Rob McElhenney packed on 60 lbs. of fat to play his character. This was something that was woven into the storyline of the season, and while it was funny, it was still alarming to see the actor that size.

As you'd expect, his diet to gain that much mass was insane.

According to the actor, "So, then I had Krispy Kreme donuts. Every morning, I would eat four of those. . . . At a certain point, it's not that fun. By the afternoon, I was drinking ice cream. I would take ice cream, and I would put it out on the counter in the morning and then it would melt. And then I would put weight gainer into it, and I would drink that every day. So then I was drinking heavily. That was a great excuse to drink wine."

He also used cottage cheese.

"I read that cottage cheese metabolizes really slowly in your stomach. If you eat cottage cheese, the last thing you want to do is eat it right before you go to bed because it metabolizes so slowly. So, I was like, 'That's what I have to do.' So, I started eating cottage cheese in the middle of the night," he said.

Eventually, the actor lost all the weight, and several years later, he debuted an entirely transformed physique on the show. This time, however, he looked like he was carved out of marble.

Related: Match The Quote To The 'It's Always Sunny' Character

He Got Shredded, But Did He Use Enhancements?

After the actor's second major transformation, people wanted to know how he did it. More importantly, people wanted to know if he did steroids to achieve the type of physique that he has.

When dishing on how he did it and how attainable it is, the actor poked some fun at himself and at wild transformations.

"Look, it’s not that hard. All you need to do is lift weights six days a week, stop drinking alcohol, don’t eat anything after 7pm, don’t eat any carbs or sugar at all, in fact just don’t eat anything you like, get the personal trainer from Magic Mike, sleep nine hours a night, run three miles a day, and have a studio pay for the whole thing over a six to seven month span," he wrote in a social media post.

McElhenney continued his post, pointing out a number of other outrageous factors needed to get shredded. He did, noticeably, leave off enhancements.

This topic has been discussed by many, and a lot of people are under the impression that the actor used to get his look.

The actor has touched on testosterone, and he has been asked about steroid use.

"I’m not going to get into the medical science of it," he jokingly said.

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So, did Rob McElhenney use steroids to get his insane physique? No one truly knows but him, but many people are convinced he isn't all natural.

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