Electronic cigarettes have come flooding on to the popular scene in the last decade, although they have actually existed for much longer. They are a controversial new pasttime due to the limited availability of research into their long term health effects. The problem isn't a lack of interest but a lack of time. E-cigarettes have simply not been around long enough for scientists to adequately assess their health risks.
Because of the before-mentioned limitations there is a lot of contradictory information out there about e-cigarettes.