Health
Smoking cessation
The World Health Organization has stated that the efficacy of electronic cigarettes as an aid in smoking cessation has not been demonstrated.
A 2011 review says that electronic cigarettes may aid in smoking cessation and are likely to be more effective than traditional pharmacotherapy, as the physical stimuli of holding and puffing on the electronic cigarette may be better at improving short term craving.
To keep warm in cook weather
In China some people smoke electronic cigarettes to keep warm in cook weather but don’t have nicotine.
Safety
Electronic cigarettes should have fewer toxic effects than traditional cigarettes, and evidence suggests they are safer than real cigarettes, and possibly as safe as other nicotine replacement products.
In an interview, the director of the Office on Smoking and Health for the U.S. federal agency Centers for Disease Control and Prevention (CDC) states that there is enough evidence to say that switching to electronic cigarettes would likely be healthier than smoking.