E-cigarettes are around 95 percent less harmful to health than tobacco and have the potential to help smokers quit smoking, according to an expert independent evidence review published Wednesday by the Public Health England (PHE), a British government agency.

The review is commissioned by PHE and led by researchers from King's College London and Queen Mary University of London.

Almost all of the 2.6 million adults using e-cigarettes in Britain are current or ex-smokers, most of whom are using the devices to help them quit smoking or to prevent them going back to cigarettes, the review showed.

Not only are e-cigarettes less harmful, the products may be contributing to falling smoking rates among adults and young people, according to the review.

Emerging evidence suggests some of the highest successful quit rates are now seen among smokers who use an e-cigarette and also receive additional support from their local stop smoking services.

"Fears that e-cigarettes have made smoking seem normal again or even led to people taking up tobacco smoking are not so far being realized based on the evidence assessed by this important independent review," said Linda Bauld, Cancer Research UK's expert in cancer prevention.

Bauld also said: "We recognize the potential benefits for e-cigarettes in helping large numbers of people move away from tobacco."