Zac Efron, who has been the subject of plastic surgery rumors over the last year, finally revealed why his appearance has changed.

During an interview with Men's Health, the High School Musical actor, 34, was asked about the validity behind the speculation he underwent plastic surgery on his jaw after he was spotted looking notably different in an Earth Day PSA shared in April 2021.

Speaking to the magazine, Efron agreed his appearance looks different today but chalked it up to an facial injury he sustained in his home.

Efron explained he shattered his jaw by running through his house with socks on. He hit the corner of a fountain, passed out and woke up to his “chin bone ... hanging off” his face.

While healing, his masseters, the muscles that raise the lower jaw, "just grew."

"They just got really, really big," Efron added.

As for what the actor thinks about others believing he may have undergone a procedure, he said that if he "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."

Efron also noted it was his mother who originally told him he looked different.

A broken jaw isn't the only injury Efron has sustained throughout the years. He has also reportedly experienced a dislocated shoulder, torn ACL, broken wrist and blown-out back — all injuries sustained while he was training.

Efron previously broke his jaw and had to have it wired shut following an accident in 2013. It's unclear if this is the same injury he referred to in his Men's Health magazine interview.

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