Daniel Radcliffe. (Charles Sykes/AP)

“I became so reliant on [alcohol] to enjoy stuff,” he told GQ U.K.. “There were a few years there when I was just so enamored with the idea of living some sort of famous person’s lifestyle that really isn’t suited to me.”

But no more. The 21-year-old actor said he’s been a teetotaler since August 2010. “As much as I would love to be a person that goes to parties and has a couple of drinks and has a nice time — that doesn’t work for me. I do that very unsuccessfully.”

The final “Potter” film opens July 15, leaving Radcliffe, who is currently starring on Broadway, determined to keep acting. “If I can make a career for myself after ‘Potter,’ and it goes well, and is varied and with longevity, then that puts to bed the ‘child actors’ argument,” he said.

For Radcliffe, it seems abstaining from alcohol completely has brought plenty of positives. “I'm actually enjoying the fact I can have a relationship with my girlfriend where I'm really pleasant and I'm not [expletive] up totally all the time,” he said. “There’s no shame in enjoying the quiet life. And that’s been the realization of the past few years for me.”