If you want to quit smoking then live in a house full of non-smokers. Smoke-free homes give family members an effective means of exerting social pressure on smokers and more leverage in changing smokers' behaviour, according to research conducted by scientists at the University of California, San Diego. Writing in Nicotine and Tobacco Research, they found that smokers were six times more likely to quit if they lived with a non-smoking adult and child than if they lived alone.