New research shows one in seven US adults have tried electronic cigarettes – a significant climb in the last few years.
But that increase is offset by a decline in the amount of people using the devices habitually.
About three percent of adults were current users in 2016, down from almost four percent in 2014, the study found.
Adults who said they have tried vaping at least once reached just over 15 percent in 2016, versus 12.6 percent in 2014. That means an estimated 33 million US adults have tried e-cigarettes, said University of Iowa researcher Dr Wei Bao, the lead author.
More is needed to understand the significance of the research, but Dr Bao warns it could mean more non-smokers may be exposing themselves to nicotine, while fewer smokers take it up as a cessation technique.
The University of Iowa study suggest more non-smokers may be exposing themselves to nicotine, and fewer smokers may be using it as a cessation technique
The decline in e-cigarette use among current smokers and increased use among former smokers suggests that some adults are using them to quit smoking tobacco.
But a rise in use among adults who never smoked tobacco is concerning, Dr Bao said.
The study was published Tuesday in the Journal of the American Medical Association.
E-cigarettes are battery-powered devices that turn liquid often containing nicotine into an inhalable vapor. They have been sold in the United States for about a decade.
The devices have been touted as a way to help smokers quit traditional tobacco products but solid evidence of that is lacking.
There is also uncertainty over their long-term health effects has raised concerns about their use, especially by teens.
Under federal law, sales are banned to those under 18.
Previous data show recent use among US teens declined in 2016 after rising in previous years. In 2016, 11 percent of US high school students and four percent of middle schoolers said they’d used the devices during the previous month.
In the new study, researchers analyzed annual US government in-person surveys for 2014 through 2016 that asked Americans aged 18 and older questions about health-related habits.
About 100,000 adults were involved.
Current use included adults who use e-cigarettes daily or just some days. Ever-use included those who frequently used the devices in the past and adults who have only tried them once.
What is an e-cigarette and how is it different to smoking tobacco?
An electronic cigarette (e-cigarette) is a device that allows users to inhale nicotine by heating a vapour from a solution that contain nicotine, propylene and flavourings.
As there is no burning involved, there is no smoke like a traditional cigarette.
But while they have been branded as carrying a lower risk than cigarettes, an increasing swell of studies is showing health dangers.
E-cigarettes do not produce tar or carbon monoxide, but the vapor does contain some harmful chemicals.
Nicotine is the highly addictive chemical which makes it difficult for smokers to quit.
Nearly three million people in Britain use e-cigarettes, and more than nine million Americans.
1. Standard e-cigarette
Battery-powered device containing nicotine e-liquid.
It vaporizes flavored nicotine liquid.
Very similar to normal e-cigarettes but with sleeker design and a higher concentration of nicotine.
Thanks to its ‘nicotine salts’, manufacturers claim one pod delivers the amount of nicotine as a pack of cigarettes.
It is composed of an e-cigarette (battery and temperature control), and a pod of e-liquid which is inserted at the end.
The liquid contains nicotine, chemicals and flavorings.
Like other vaping devices, it vaporizes the e-liquid.
3. IQOS by Philip Morris
Pen-shaped, charged like an iPod.
It is known as a ‘heat not burn’ smokeless device, heating tobacco but not burning it (at 350C compared to 600C as normal cigarettes do).
The company claims this method lowers users’ exposure to carcinogen from burning tobacco.