Many people assume vaping encourages people to smoke cigarettes.

But now scientists claim this is just a myth - and that evidence to even suggest such a link is 'weak'.

Despite having long been considered a gateway, a team of US researchers wanted to analyse the findings of previous studies.

They highlighted several shortfalls that appear to show a link between e-cigarettes and traditional tobacco products.

For example, they said many use misleading measurements for what they consider to be 'smoking', including just one puff over a course of six months.

Despite having long been considered a gateway, a team of US researchers claim that evidence is 'weak' to suggest e-cigarettes encourage people to smoke tobacco products

Dr Lynn Kozlowski, of the University of Buffalo, pointed to research that shows as use of e-cigarettes have shot up, overall smoking rates have decreased.

Writing in the journal Drug and Alcohol Dependence, she said: 'The evidence from the prospective studies is weak at best.

'The national trends in vaping and cigarette smoking do not support the argument that vaping is leading to smoking

'There is little evidence that those who have never smoked cigarettes or never used other tobacco products and first try e-cigarettes will later move on to cigarette usage with great frequency or daily, regular smoking.

Pointing to other previous studies, Dr Kozlowski also noted how no research has been designed to follow up smoking intensity.

She also pointed to the fact that many have avoided looking into details of e-cigarette flavourings that contain no nicotine.

A 2015 survey found that only 20 per cent of students who had used the gadgets reported it containing nicotine.

E-cigarettes contain a liquid form of nicotine that is heated into vapour to be inhaled, avoiding the harm caused by tobacco smoke.

Dr Lynn Kozlowski, of the University of Buffalo, said: 'The public deserves accurate information on the health risks of e-cigarettes versus cigarettes'

Health experts agree that the devices are much safer than smoking tobacco – and the gadgets are designed to help people quit smoking each year.

The evidence from the prospective studies is weak at best Dr Lynn Kozlowski, of the University of Buffalo

But many are concerned about unresolved safety concerns. In November, the World Health Organisation called for a global ban on using e-cigarettes in public places.

It warned of the dangers of 'passive vaping', which growing evidence has linked to lung damage, heart complications and stillbirth in pregnant women.

E-CIGARETTES ARE SAFER Electronic cigarettes are far safer and less toxic than smoking tobacco, a major British study found in February. Scientists warned nearly two thirds of smokers wrongly believe e-cigarettes are as dangerous as smoking. And they blamed US campaigners for exaggerating the harms as part of a 'moral crusade' against the nicotine devices. Researchers at University College London found people who switched from tobacco to 'vaping' gadgets saw the levels of cancer-causing toxins in their body drop by up to 97.5 per cent in six months. Advertisement

However, a major British study last month found that electronic cigarettes are far safer and less toxic than smoking tobacco.

Dr Kozlowski added: 'The public deserves accurate information on the health risks of e-cigarettes versus cigarettes.

'From the best evidence to date, e-cigarettes are much less dangerous than cigarettes. The public has become confused about this.'

And the constant focus on the potential risks of e-cigarettes to children has caused many to become confused over the dangers.

Dr Kozlowski said that this is likely 'discouraging adult smokers from using e-cigarettes as a smoking cessation tool'.

This comes after scientists at the University of Michigan warned last month that e-cigarettes are a 'one-way bridge' to smoking tobacco.

The study found using the gadgets desensitised teenagers, meaning they were four times as likely to go on to smoke cigarettes.