The number of Scottish adult smokers turning to e-cigarettes to help them give up the habit has risen fivefold since 2010.
Use of the electronic devices that imitate the effect of cigarettes has risen from 3% of former smokers four years ago to 17% today, new figures reveal.
According to a survey commissioned by anti-smoking charity, Ash Scotland, the rise shows the need for regulation of the market for the products and stricter controls.
The YouGov poll of 1000 people shows use of e-cigarettes among former smokers in Scotland was 3% in 2014. But the survey of reveals a dramatic rise in the number of smokers in Scotland who have tried electronic cigarettes over the past four years.
In 2010, only 7% of current smokers had ever tried electronic cigarettes. By 2014, the figure had risen to 45%.
But 31% of adults who have heard of e-cigarettes believe they will be good for public health, while agreement was even higher among smokers (55%).
Ash Scotland chief executive Sheila Duffy said they believed e-cigarettes would prove to be less harmful than smoking "but not harmless, as some supporters suggest".
The organisation is calling for regulation of the market in e-cigarettes because the companies involved were under strong commercial pressure to recruit young people into using it, she said.
A spokesman for British American Tobacco said "E-cigarettes enable us to offer adult consumers a range of potentially reduced-risk products."