Smoking is the most preventable cause of death, causing nearly 6 million deaths worldwide every year. At current rates, this figure is projected to reach more than 8 million by 2030.

Now, new research suggests that puffing e-cigarettes may be more effective in helping smokers quit than other existing nicotine replacement methods, like nasal sprays, patches, lozenges, and gum.

But some health practitioners remain wary of embracing e-cigarettes due to concern over the rise of vaping among teenagers — especially in the United States. Is there a trade-off between making e-cigarettes available as a cessation tool and the risk of getting nonsmokers hooked on nicotine?

A new study in the New England Journal of Medicine found that vaping was nearly twice as effective in getting people off smoking than other traditional methods. The study examined 886 smokers who attended smoking cessation services in the United Kingdom, roughly half of whom were put on e-cigarettes, while the other half were assigned other nicotine replacement therapies. Both groups were also given counseling concurrently. After one year, 18 percent of the people who were vaping had abstained from smoking, compared to 9.9 percent of people using other measures.

Results of the new trial should encourage doctors and other health professionals to recommend e-cigarettes to people looking to quit smoking, says study co-author Peter Hajek, a psychologist at the Queen Mary University of London. If vaping is “a way of stopping smoking for people who otherwise find it difficult, that must be a good thing,” he says.

Lion Shahab, a health psychologist at University College London who was on the data management committee for the new study but is not an author, described the new paper as a “landmark trial,” noting that until now, there were only a handful of studies that looked into the effectiveness of e-cigarettes.

Vaping is “orders of magnitude” safer than smoking cigarettes, Shahab says. His own 2017 study suggests that people who switched from smoking to e-cigarettes or other nicotine replacement therapies for at least six months had significantly lower levels of toxic chemicals and carcinogens in their body compared to smokers.

The study was “well conducted,” says Humberto Choi, a pulmonologist at the Cleveland Clinic in Ohio. But for him, it doesn’t provide sufficient evidence to use vaping as a smoking cessation treatment. He points out that 80 percent of people in the e-cigarette group were still vaping after a year, while only 9 percent of those who quit using other methods were still using their cessation products. The study participants used e-liquid with a concentration of 18 milligrams per milliliter, but Juul, the most popular brand in the United States, sells higher concentrations. Choi also notes that people who go to smoking cessation clinics and receive regular counseling may already be motivated to quit, which is not the case for many smokers.

“It will take us years to learn what the long-term health risks are.”

In November 2018, the U.S. Food and Drug Administration (FDA) announced new regulations for e-cigarettes. In the future, flavored e-cigarettes will only be available at age-restricted stores or on websites that verify customers’ ages. The move followed a survey that found a 78 percent rise in e-cigarette usage among high school students in the United States from the previous year. More than 20 percent of all U.S. high school students had used e-cigarettes, the survey found. “I will not allow a generation of children to become addicted to nicotine through e-cigarettes,” FDA Commissioner Scott Gottlieb said at the time.

For Choi, the rapid rise of vaping among U.S. teens is especially concerning. He worries that vaping teenagers will get addicted to nicotine and move onto more harmful products like regular cigarettes. Choi points to a recent survey of 6,000 American youths that suggests that young people who start vaping are four times more likely to also start smoking cigarettes.

“It will take us years to learn what the long-term health risks are,” Choi says, similar to how it took decades to find that smoking cigarettes causes lung cancer. But his hunch is that e-cigarettes will do more harm than good in the long run. Instead, he thinks smokers should take the prescription drug varenicline (brand name Chantix and Champix), which, he says, may be more likely to work.

Hajek, however, thinks vaping will ultimately make cigarettes obsolete. “We will see, in the next 10 years or so, smoking eventually disappearing,” he says.