Zac Efron says shattering his jaw put him at the centre of plastic surgery rumours last year.
The 34-year-old actor finally revealed what caused his facial transformation in 2021 in a cover interview for the October 2022 issue of Men's Health magazine.
He said he swelled up and had muscles going into overdrive after he broke his jaw so badly after running in the house with socks on, slipping, and bashing his chin against the granite corner of a fountain, that he woke from unconsciousness to find his "chin bone was hanging off his face".
Zac added masseter muscles on the inside of his face and jaw had to work overtime amid the injury, explaining his different look.
He said: "The masseters just grew. They just got really, really big."
Zac also claimed not to have known he went viral for his different looking jaw until his mother called to ask if he had undergone cosmetic surgery.
In April 2021, Efron started trending on Twitter after he was seen on a video for Earth Day! The Musical displaying a far more prominent square chin and heavier jawline.
Zac's friend Kyle Sandilands has declared the actor would never go under the knife.
The Australian radio host, 50, who has known Zac for years, said during The Kyle and Jackie O Show: "I would know if he'd had any plastic surgery.
"It's like getting a Picasso and having a kid finger paint all over it. Why bother?"
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