Kristen Stewart gave up smoking after realising she wasn't addicted to cigarettes.
The actress, who is currently promoting 'The Twilight Saga: Breaking Dawn – Part 2', only continued to smoke out of habit but never felt a physical longing for nicotine.
Speaking on American chat show Conan, the 22-year-old said: “I was a bit of a faker, a circumstantial smoker. I just feel like I wasn't addicted to nicotine. I just wanted something in my mouth."
Looking embarrassed, she added: “Why did I do that?”
And while Kristen claims she simply quit smoking because she found it easy, a friend recently revealed she really gave up the habit to support boyfriend Robert Pattinson.
A source told HollywoodLife.com: “Kristen has never been better. She is probably in the best shape of her life and best health, thanks to Rob. She has given up smoking.
“She has been trying to be as supportive as she can of Rob's decision to quit. Kristen and Rob used to smoke cigarettes together all the time but they know how c**ppy it made them feel...
“Kristen realised that her smoking was getting out of hand. On movie sets, it's really tempting to smoke a lot while waiting and there is so much waiting and down time. Kristen feels really good about herself since quitting.”
Here's some pictures of Kristen and Robert at the Twilight Saga: Breaking Dawn - Part 2 premiere...