Keira Knightley insists she must be coping with being famous because has not become a drug addict.

The 29-year-old actress shot to fame as a teenager in 2002 comedy/drama movie 'Bend It Like Beckham', and she feels grateful that she hasn't gone down the route of becoming addicted to illegal substances like some celebrities who became famous at an early age.

Speaking about her rise to fame, she said: ''Luckily it was so long ago that I can't remember what it was like when it happened. But I'm still here, I'm still alive and I'm not a drug addict so it must have been all right. ''

The 'Begin Again' star is married to Klaxons vocalist James Righton and admits it seems a lot more common for young musicians than movie stars to become embroiled in a world of drugs because they live their lives as ''extremely as they can''.

She added to Loaded magazine: ''They very much walk that line. A lot live life as extremely as they can, and that's absolutely fascinating for so many people and has been since the beginning of time.

''We've been fascinated by youth that has absolutely no fear of anything and could corrupt and could die at any second. It's the moth-to-the-flame thing. So much of rock 'n' roll is about that.''

The latest issue of Loaded magazine - with Pharrell Williams on the cover - is available to buy now.