Are e-cigarettes safe and effective?

Medical experts have questioned the evidence on safety and effectiveness, underpinning the recommendations of e-cigarettes.

Researches from the London School of Hygiene and Tropical Medicine and University of Liverpool have argued that the available evidence about e-cigarettes suggested that the debate was far from over and questions remain about their benefits and harms.

A recent review concluded that the available evidence, of e-cigarettes being safe, was of 'low or very low quality' by recognized standards.

The report also found serious methodological problems in many of the studies it reviewed, and noted that one third of the studies it reviewed were published by authors with conflicts of interest.

Researchers Martin McKee and Simon Capewell have described the report's dismissal of the possibility that e-cigarettes might be a gateway to smoking as 'premature,' arguing that the report had many other omissions, such as concerns about product safety, and the lack of evidence of risks from long term dual use with conventional cigarettes.

They concluded that directors of public health and the wider community desperately needed advice on e-cigarettes that was evidence based and free from any suspicion of influence by vested interests.

The study is published in the Journal BMJ.