The first Cochrane Review on this subject will be published next week in the Cochrane Library.
This new emerging evidence gives some early insights into how effective e-cigarettes are as an aid to stopping smoking.
This is an active area of research and this review draws on the first randomised trials that have been done.
Experts came to the Science Media Centre to discuss their findings, which aimed to answer the question: do electronic cigarettes help smokers to quit?
Prof Peter Hajek, Professor of Clinical Psychology and Director of the Tobacco and Dependence Research Unit at Barts and The London School of Medicine and Dentistry, Queen Mary University of London
Ms Jamie Hartmann-Boyce, Nuffield Department of Primary Care Health Sciences, University of Oxford
Mr David Tovey, Editor in Chief, Cochrane Editorial Unit, The Cochrane Collaboration