A lot of young people who smoke e-cigarettes eventually smoke traditional cigarettes, according to a study into the connection between the two forms of smoking. But the question remains whether e-cigarettes are a gateway to smoking cigarettes or if those kids would have taken up the habit anyway.

Electronic cigarettes create a vapor that commonly contains nicotine and different flavorings. They are generally considered to be healthier and safer than regular cigarettes because they don’t contain tobacco and users aren’t inhaling toxic smoke. But there has been debate over whether e-cigarettes provide an outlet that will decrease smoking rates or whether they will lead more people to become addicted.

The researchers behind this study, published in the Canadian Medical Association Journal, were trying to determine if e-cigarettes had an effect on “smoking initiation” — a young person’s entry into the cigarette-smoking population. They got the data from a group of almost 45,000 Canadian high school students, who self-reported their cigarette and e-cigarette use. That data also included follow-up with the kids in Ontario and Alberta a year later.

Exploration into this age group is key to understanding smoking initiation because, according to the researchers, most smokers pick up their habit as adolescents and decreased nationwide smoking rates have come from deterring young people.

“The influence of e-cigarette use on smoking initiation is a highly controversial issue,” the study says. Results from the research suggested that “e-cigarette use was strongly associated with cigarette smoking behavior, including smoking initiation at follow-up.”

Specifically, the results suggested that if one of the high school students had reported using an e-cigarette in the last 30 days during their first data collection, that student was more likely to report at their one-year follow-up having smoked cigarettes, including on a daily basis.

“At the individual level, e-cigarettes may be causally related to cigarette smoking because they provide early exposure to nicotine or greater exposure to environmental risk factors, including greater exposure to smokers or certain social settings,” the study says. “E-cigarette use may also help to ‘re-normalize’ smoking by promoting more positive normative beliefs about nicotine use and smoking, which are important predictors of uptake.”

But that doesn’t account for other personal reasons adolescents start smoking. The study also considered those factors, which could include things like family life.

“Put more simply, youth who try e-cigarettes may be different from those who do not,” and they might be trying e-cigarettes first because they are easier to get a hold of, the authors wrote.

Despite the research showing an association between e-cigarettes and cigarette smoking, it is minimal — at least for now. A report from the medical journal on the research notes that overall smoking rates have decreased.

That report also noted that the results may not apply to other countries like the United States, where smoking advertising and e-cigarette sales are regulated differently.