There can no longer be any dispute: electronic cigarettes, also known as “vapes,” are significantly less harmful to health than traditional combustible cigarettes. Not only are they less harmful, they are more effective in helping adults quit their deadly cigarette habit than any other nicotine-replacement therapy. Despite this, some within the public health community continue efforts to eliminate these potentially life-saving products. San Francisco just passed a ban on the sale of flavored tobacco products, in part over concerns that fruit and candy-flavored e-cigarettes appeal to kids. But fears aren’t facts, and such efforts could have devastating consequences for public health.

In March, five prominent health organizations issued a joint report arguing that tobacco companies are luring kids, “enticing them with a booming market of sweet-flavored tobacco products,” and urged the U.S. Food and Drug Administration (FDA) to restrict flavors to just tobacco and menthol as it did for traditional cigarettes. Since then, cities in the Bay Area—a trailblazer in reactionary public health policy—have taken up the charge, with measures to restrict vape flavors introduced in Oakland, Los Gatos, Palo Alto, San Francisco, and San Leandro.

Despite the existence of vape flavors like “strawberry” or “gummi bear,” a 2015 Journal of Nicotine & Tobacco Research study found that e-cigarettes had little appeal to nonsmoking teenagers and that the availability of flavor varieties had no effect on their level of interest. It can’t hurt that an average disposable e-cigarette costs around $9 per unit in California, and the product is illegal to sell to minors. Actual candy, on the other hand, is widely available, legal, and a lot less expensive.

That said, the uncomfortable reality is that a certain number of teens will always experiment with “adult” products, whether nicotine, caffeine, or alcohol. Nicotine, while approximately as dangerous as caffeine, is an addictive chemical, and nobody wants to encourage its use by young adults. The difficult but important question not being addressed is: if young people are going to experiment with nicotine, wouldn’t it be better for public health if they chose a less harmful form? For public health advocates, the answer is clearly no. They believe that even experimenting with e-cigarettes leads to nicotine addiction and, ultimately, lifelong cigarette use. But the evidence doesn’t bear that out.

While it is true that e-cigarette use among teens has significantly increased over the years, the vast majority of habitual teen vapers are current or former smokers. A 2016 study published in the American Journal of Preventive Medicine found that only six percent of 12th graders who had never smoked had used e-cigarettes in the last month and, of that number, less than one percent used them on a regular basis. Put another way, the vast majority of teen e-cigarette users are current or former tobacco smokers.

Even if more teens are vaping, the good news is that since the introduction of e-cigarettes, teen use of traditional cigarettes has taken a nosedive, hitting single-digit levels—its lowest rate ever. Many researchers believe the availability of e-cigarettes has driven this decline in teen cigarette use. In other words, e-cigarettes are likely not “luring” in teens who would otherwise never have used nicotine-containing products, but rather may be diverting teens who were already smoking or going to smoke toward a less-harmful option.

Still, there will be those health advocates who claim we should do whatever it takes to prevent even a small number of non-smoking teens from developing nicotine addictions. This raises another uncomfortable but necessary question: what if efforts to reduce teen vaping, such as the proposed flavor ban, result in greater rates of adult smoking?

Despite what anyone wants to believe, adults actually like flavor. Research indicates that fruit and candy-flavored vapes are not only appealing to adults but also may help them stick to vaping, decreasing the odds that they will return to smoking traditional cigarettes. For example, in a 2014 consumer survey of adult e-cigarette users, approximately 61 percent cited fruit, dessert, candy, savory, and beverage-flavored liquids as their primary flavor. Just 25 percent cited tobacco or menthol-tobacco as their main flavor choice. A 2013 study published in the International Journal of Environmental Research and Public Health found that most adult vapers actually rely on multiple flavors and that the majority rated a variety of flavors as “very important” in their ability to reduce or quit smoking. Half of those in this study indicated that a restriction on vape flavors that would limit options to tobacco and menthol, like those proposed in California, would increase their cravings for traditional cigarettes and the likelihood they would return to smoking.

Protecting children is a laudable goal, but they are not the only demographic that matters. And, if we want to make sure that public health proposals do more good than harm, they cannot be based on blind fear or assumptions. In the case of banning e-cigarette flavors, evidence indicates it would have little to no effect on teen e-cigarette use but may have potentially catastrophic consequences for adult smokers.

Michelle Minton is a fellow with the Competitive Enterprise Institute, a free market public policy organization based in Washington, DC.