As legislators decide how to regulate e-cigarettes Discovery looks at the health impacts and asks whether they really help smokers. And, how safe are they?

Lorna Stewart reports on the new and growing phenomenon of electronic cigarettes and asks if they really help smokers to stop smoking and if they are as safe as their manufacturers suggest.

One billion people smoke worldwide and tobacco shortens the lives of half of all users. With consumption of tobacco products increasing globally, finding a way to help smokers to quit is vital. Electronic cigarettes, which contain nicotine in water vapour, are one new approach, but there is very little research into whether they have any harmful effects.

As legislators worldwide start to rule on how to regulate them, there are concerns over who might use e-cigarettes; in some places they are proving popular with young people. Issues surrounding nicotine use and addiction have led regulatory bodies around the globe to act, and e-cigarettes are now banned in Brazil, Canada, Singapore, Panama and Lebanon.

In this episode of Discovery for the BBC we hear from public health experts, psychologists, and e-cigarette enthusiasts about what e-cigarettes offer and what the risks are.

Image: Man exhaling fumes. Credit: Atif Tanvir from ukecigstore