Justin Bieber won't get drunk because he likes being in control.

The 18-year-old singer admits he has experimented with alcohol but would never drink to excess.

He said: ''For me, it's like I like to be in control of myself. I mean, I've had a beer, like, before... But I never get out of control.''

Justin's manager, Scooter Braun, believes the 'Boyfriend' hitmaker's caution stems from his desire not to damage his career.

Told about the star's remarks, he told America's GQ magazine: He knows that I hold him to a high standard... He doesn't want to blow it.''

Justin - who is dating Selena Gomez - also admitted he struggles to trust people after having bad experiences in the past.

He said: ''I mean, I keep my guard up a lot, because you know, you can't trust anyone in this business.

''That's what's sad. You can't trust anybody. I learned the hard way.''

The 'Never Say Never' hitmaker also praised his friend Kim Kardashian for her strong work ethic.

After a member of his entourage slammed an outfit she was wearing in a picture, he said: ''You guys are so mean, bro... People say she doesn't do anything; she actually does do stuff... She works hard.''