Zac Efron

The '17 Again' actor explained how he found it a "never-ending struggle" to keep his drug and alcohol issues in check as he adjusted to the teenage stardom that resulted from his role in 'High School Musical'.

He told the Hollywood Reporter in 2014: "I was drinking a lot, way too much. It's never one specific thing. I mean, you're in your 20s, single, going through life in Hollywood, you know? Everything is thrown at you.

"It's a never-ending struggle, [but] I just started going [to counselling]. And I think it's changed my life. I'm much more comfortable in my own skin. Things are so much easier now."