Mischa Barton has drinking 'fasts'

Mischa Barton keeps her drinking under control by giving up alcohol for six-week "fasts".

The O.C. star stays healthy by ditching booze for long periods of time, but insists she hasn't given up for good.

She tells British newspaper The Daily Mail, "I don't want to give up booze completely but I now have regular six-week fasts when I don't touch a drop and it seems to work for me...

"I've never had a serious problem with drink really, just a couple of high-spirited incidents when I was younger. But I've grown up a bit now."

Barton checked into rehab after a drink driving arrest in 2007. She was sentenced to 36 months on probation, alcohol education classes and a fine, but she also enrolled in a private program to "prove I was sober".

She previously said of the experience, "It really helped in getting the more serious aspects of my case dropped because, you know, that's what they want to hear; you're not an alcoholic and you don't have a problem. So I did it in the most low-key way possible... I just did the program and got through it."