It is a popular method for smokers hoping to give up their habit. But vaping could be doing them more harm than good.
In fact e-cigarettes could be as bad for the heart as cigarettes, according to a new study.
Using one of the devices had a similar effect on the heart’s main heart artery as smoking a normal cigarette, trials found.
The research comes amid growing controversy surrounding e-cigarettes. Last year Public Health England claimed vaping was 95 per cent safer than smoking.
GPs will soon be able prescribe e-cigarettes to those giving up smoking.
But now researchers at the European Society for Cardiology congress in Rome said such a move was premature, according to the Daily Telegraph.
British heart experts said the findings showed that more research was needed to assess the long-term safety of e-cigarettes.
In the trial, adult smokers had their hearts monitored while they vaped, and also smoked ordinary cigarettes.
Smokers who want to give up often turn to e-cigarettes
The effects of a 30-minute vaping session – that researchers claimed is typical – were similar to those from five minutes of smoking, the study found.
Lead researcher Prof Charalambos Vlachopoulos, from the University of Athens Medical School said: “We measured aortic stiffness. If the aorta is stiff you multiply your risk of dying, either from heart diseases or from other causes.”
“The aorta is like a balloon next to the heart,” he said. “The more stiff the balloon is, the more difficult for the heart to pump. It’s the most powerful biomarker we have for estimating cardiovascular risk.”
The experiments only examined the immediate effects, but Prof Vlachopoulos said the long-term risks remain unknown, but that he would not recommend using e-cigarettes.
Official data shows that 2.2 million Brits regularly used e-cigarettes in 2015.
Prof Peter Weissberg, medical director at the British Heart Foundation, said: “The study…shows that [they] cannot be assumed to be risk free.
"Much more research is needed to establish the safety of long-term use of these devices.”
However, Deborah Arnott, from Action on Smoking and Health, said: “This study does not prove that e-cigarettes are as hazardous as smoking.”
She highlighted other findings from the study, showing that if a vaping session was limited to five minutes, the impact on aortic stiffness was significantly less than that associated with a cigarette.
Tom Pruen, of the Electronic Cigarette Industry Trade Association, told the Telegraph: “Lots of things have short term effects on aortic stiffness - and nicotine is already known to do this. On the other hand, so does caffeine, and in both cases it is transitory, without any significant long term effect.”
Rosanna O’Connor, from Public Health England, said: “Vaping carries a fraction of the risk of smoking.”