A report by the Royal College of Physicians supports the use of e-cigarettes by current smokers. Other experts agree but urge caution.

Picture Jenny McCarthy or Johnny Depp or Katy Perry out in public with an electronic cigarette in hand, stylishly dressed, and exuding a vapory air of sex appeal.

These images are signs of the growing popularity of e-cigarettes, the glowing tip of these devices acting like a beacon to lure in current smokers and newcomers alike.

They also bring to mind past marketing campaigns of the tobacco industry, designed to boost the “coolness” of conventional cigarettes.

But while there are similarities with conventional cigarettes, e-cigarettes have the potential to help smokers live healthier lives.

Well, healthier than chain smoking tobacco cigarettes laden with carcinogens, carbon monoxide, and other toxins.

That’s the conclusion of a new report by the Royal College of Physicians, a professional organization for doctors in the United Kingdom, who write, “The availability of e-cigarettes has been beneficial to U.K. public health.”

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Whether e-cigarettes are less harmful than conventional cigarettes is no longer a big debate among health professionals.

“The consequences of smoking combustible cigarettes are so dire that virtually any way to quit is preferable to continuing to smoke. That certainly includes the use of e-cigarettes as a substitute,” Dr. Steven Schroeder, a professor of health and healthcare and the director of the Smoking Cessation Leadership Center at the University of California, San Francisco, told Healthline in an email.

Exactly how much better e-cigarettes are for you is unknown.

But the RCP report says that the “hazard to health arising from long-term vapor inhalation from the e-cigarettes available today is unlikely to exceed 5 percent of the harm from smoking tobacco.”

So for smokers, switching to e-cigarettes can be a plus for their health. But for non-smokers, taking up “vaping” won’t do their body any favors.

“It is likely that e-cigarette exposure is less safe than ambient air,” said Schroeder, “and the evidence to date especially points to the toxicity of the flavor ingredients added to the e-cigarette vapor.”

The toxic chemicals in e-cigarette vapor include the carcinogens formaldehyde and acetaldehyde. Some high-voltage e-cigarettes can produce these chemicals at levels similar to conventional cigarettes.

The lack of regulation of the e-cigarette industry also means that chemicals present in the vapor can vary among products.

“There have been many reports of adulterants in the vapor such as heavy metals and harmful, volatile, organic compounds,” Dr. Hilary Tindle, M.P.H, an associate professor of medicine and the founding director of ViTAL, the Vanderbilt Center for Tobacco, Addiction and Lifestyle at Vanderbilt University, told Healthline in an email.

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According to the World Health Organization (WHO), worldwide there are around 1 billion smokers. Eighty percent of them live in low- and middle-income countries.

If they all switched to using electronic cigarettes, “there would be massive harm reduction,” said Tindle, but “the harm reduction would not be as much as if people quit using tobacco or nicotine altogether, and this point is often lost in these discussions.”

E-cigarettes are often touted as a good way to quit smoking, but do they work?

“To date the evidence is mixed,” said Schroeder, “but it is likely that some smokers are able to quit using e-cigarettes.”

Many have tried.

According to a 2015 survey by the Centers for Disease Control and Prevention (CDC), more than half of smokers who tried to quit in the past year had tried an e-cigarette at some point. And around one-fifth of these people were currently using e-cigarettes.

The RCP report also found that e-cigarettes helped smokers quit. However, this was only true if they received these devices through a health professional.

Some studies, though, show that people who use e-cigarettes are less likely to quit smoking.

One danger is that smokers who start using e-cigarettes to quit may just end up using them alongside conventional cigarettes.

These “dual-use” smokers “may think they’re being healthier but in fact are still at risk of smoking-related illness such as heart disease,” said Tindle.

Also, other approaches for stopping smoking have much more research to show that they are effective. This includes counseling, telephone quit lines, and FDA-approved medications.

These can also help smokers move from e-cigarettes to nicotine-free, which is a good thing.

“Those who do rely on e-cigarettes to quit should be urged to stop them as soon as possible,” said Schroeder.

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One of the biggest concerns among health officials is that e-cigarettes will hook another generation on nicotine, or that e-cigarettes may lead children to experiment with conventional cigarettes.

A 2015 CDC report found that use of e-cigarettes continues to grow among youth. Their use has also surpassed the use of conventional cigarettes, which had been falling but plateaued in recent years.

There is still debate about whether e-cigarettes are a gateway device to conventional cigarettes. But some people are concerned about the use of nicotine in any form.

“There is good evidence to advocate not exposing adolescent brains to nicotine, so youth experimentation with e-cigarettes should be avoided,” said Schroeder.

Along with this is concern about the “relentless marketing” of e-cigarettes to youth, using tactics similar to ones employed by the tobacco industry for conventional cigarettes.

“We need to do a better job of protecting our kids from the brutal marketing tactics that use flavoring and the ‘cool factor’ to turn our kids into the next generation of paying customers for nicotine products,” said Tindle.

Read More: E-Cigarette Use Among Teens Continues to Rise »