Zac Efron Reveals What Caused His Face to Look So Different in That 2021 Viral Video

Zac Efron finally addressed the speculation that he got plastic surgery on his jaw. Back in April 2021, the High School Musical star looked shockingly different in an Earth Day Musical special with Bill Nye. Some fans theorized he had some work done, but Efron told Men's Health this week that it stemmed from a jaw injury.

Starting about four years ago, as he recovered from his physically demanding transformation for the 2017 Baywatch movie, Efron suffered a series of injuries in a short span. He tore his ACL, dislocated his shoulder, broke his wrist, and threw out his back. He also shattered his jaw when he ran through his house in socks back in November 2013, as PEOPLE reported at the time. His chin hit the granite corner of a fountain, knocking him unconscious. When he woke up, his chin bone dangled from his face, he told Men's Health.

After he was injured, the muscles in his face and jaw compensated for his masseter muscles not operating "like a symphony," Efron said. The masseter muscles are along the face and are used for chewing. He works with a specialist and does physical therapy to recover from the injury.

However, while filming Netflix's Down to Earth in Australia, he took a break from therapy. "The masseters just grew" during that period, Efron said. "They just got really, really big."

Efron, 34, said he was not even aware of "Jaw-gate" until his mother asked if he had plastic surgery. He told Men's Health he usually avoids social media, although he is fine with using it for promoting his projects. Since he has been a public figure since age 17, he understands the importance of keeping his private life private. "If I valued what other people thought of me to the extent that they may think I do... I definitely wouldn't be able to do this work," he said.

Elsewhere in his new interview, Efron spoke about the dangers of creating that chiseled physique he showed off in Baywatch. He said he is bulking up again for an unannounced project, but he is going about it a different way. "That Baywatch look, I don't know if that's really attainable. There's just too little water in the skin. Like, it's fake; it looks CGI'd," he said. "And that required Lasix, powerful diuretics, to achieve. So I don't need to do that. I much prefer to have an extra, you know, 2 to 3 percent body fat."

Efron opened up about the Baywatch experience know because he wanted people to understand the dangers of overworking. He developed insomnia and fell into a "pretty bad" depression. "Something about that experience burned me out. I had a really hard time recentering. Ultimately they chalked it up to taking way too many diuretics for way too long, and it messed something up," he said. It was six months before he finally felt himself.

Efron's next project is the Apple TV+ movie The Greatest Beer Run Ever, Peter Farrelly's follow-up to Green Book. The movie will debut at the Toronto International Film Festival on Sept. 13 and opens in the U.S. on Sept. 30. Efron plays John Donohue, a real-life Vietnam War veteran who went back to deliver beer to service members in 1968.