Austin Butler followed popular diet beloved by celebs to get into shape for latest role

Austin Butler has been through it for his roles. He was hospitalised during Elvis for a virus and even said he temporarily lost his vision while filming The Bikeriders.

So, when it came to preparing for his latest upcoming project Enemies with Jeremy Allen White, his trainer knew he needed a method that wasn’t just about pushing harder - it had to be smarter.

Enter the Roydian Method, a system his coach swears by, built on three pillars: fitness, recovery and nutrition.

And when it came to nutrition, Butler didn’t follow the typical chicken-broccoli-rice grind. His trainer Roy Chan wanted something more realistic - something he could actually stick to - after being Butler found he had just 14 weeks to go from playing an alcoholic former baseball player in Caught Stealing (which saw him put on at least 30lbs) to a much leaner character for Enemies.

Austin Butler with Zoe Kravitz while promoting his recent film Caught Stealing (ANGELA WEISS/Contributor/Getty)

"Our philosophy is based on clean moving mechanics," Chan told GQ.

"We’re not loading you with movements if your foundation isn’t there. So there are three pillars of the Roydian method: fitness, nutrition, recovery. The nutrition part plays a really huge role."

He went on: “We approached his nutrition with an 80/20 rule. Eighty percent of the time we stay pretty committed with fitness, nutrition and recovery. But 20% of the time, you should enjoy your life. So let’s say you average three meals a day, that’s about 20 meals a week. If you stick to eating well for 16 of those meals, there’s room for you to have a little of whatever to enjoy your life. Because what's the point of doing all of this if we can’t enjoy our lives? Just don’t eat like an asshole.”

That meant Butler could actually keep some of his favourites in rotation - like sweet potatoes, which his trainer said he 'loves, loves, loves' - while still building the kind of physique Hollywood demands.

But does this 80/20 diet - also favoured by the likes of Jennifer Aniston, Tom Brady and Drew Barrymore - actually work, or is it just another celebrity gimmick?

Thankfully, dietitians seem to rate it as much as the A-listers, with Sapna Peruvemba, a vegan registered dietician and founder of Health by Sapna, advocating for the 80/20 rule.

“It’s a sustainable way to enjoy your meals without feeling deprived,” Peruvemba told Veg News.

“I’m a fan of this philosophy and follow it myself, as it can be a refreshing outlook on eating when done in a healthy way. Think of it as your food compass—gently guiding you toward balance without veering too far off course.”

Dietitian Sophie Medlin also told FOODBible there’s some solid reasoning behind it: “It allows flexibility and enjoyment, which is really important for long-term success. It’s less about restriction and more about sustainable habits.”

The 80/20 diet dictates healthy eating 80% of the time while indulging for 20% (fcafotodigital/Getty)

The catch is that you can’t treat that 20% like a free-for-all. “Some people will hear 20% and think that means they can eat absolutely anything with no limits, but that’s not the case,” Medlin explained. “The quality of your overall diet still matters, and too much processed or high-sugar food can still have negative effects.”

So while Austin Butler’s abs probably came from a lot more than a few sweet potatoes and cheat meals, the approach highlights something refreshing: you don’t need perfection to see results. You just need consistency - and maybe permission to enjoy a slice of pizza without the guilt.