Woody Harrelson has swapped marijuana for yoga, because the spiritual practice gives him a better high, without the lows.

The actor has long been a poster boy for smokers of the drug - but is attempting to get healthy, and had found enormous benefits from a more active, weed-free lifestyle.

He says, "Yoga and smoking a joint are very similar things. One, you take the elevator to the top floor, and the other you climb up the mountain. But the one gives you ultimately a deficit., whereas the yoga continually pays dividends.

"I do think it helps me. You can look in my eyes and probably see there's some kind of agitation in there."