E-cigarettes do far more harm than good, says a recently released study funded by the National Health Institutes of the United States.

It found that for every smoker who quits with the help of e-cigarettes, 80 others would pick up the habit following exposure to e-cigarettes. This lends strong support for Singapore's total ban on e-cigarettes that became effective last month (February).

The study, led by Associate Professor Samir Soneji of the Dartmouth Institute, the health services research and education centre at Dartmouth College, was based on simulation modelling.

The model estimates that use of e-cigarettes in 2014 in the US would lead to an additional 2,070 adults quitting smoking in 2015.

However, it expects e-cigarettes to initiate smoking in 168,000 young people who had never smoked to become daily smokers by their mid-30s.

It concluded: "E-cigarette use currently represents more population-level harm than benefit."