THE UPSIDE OF TEEN VAPING.

• Author: Sullum, Jacob
• Position: DRUGS

THE FOOD AND Drug Administration (FDA), which responded to an "epidemic" of underage vaping by imposing restrictions on sales of flavored e-cigarettes, admits the policy may deter adult smokers from making a switch that could save their lives. According to the FDA, the price is worth paying to prevent teenagers from using e-cigarettes. But that goal is itself questionable on public health grounds.

FDA Commissioner Scott Gottlieb, who announced the flavor restrictions four months before he revealed that he'd be leaving the agency in April, said he worried that vaping might be a gateway to smoking. Yet there is little evidence of that.

A study published by the Journal of the National Cancer Institute in January, based on a sample of 12,000 12- to 17-year-olds who were surveyed on two occasions one year apart, confirmed that teenagers who try e-cigarettes are more likely than those who don't to subsequently try conventional cigarettes. That finding is consistent with Gottlieb's fear. But it is also consistent with the hypothesis that pre-existing differences make some teenagers more likely to experiment with both products.

Notably, past-month vaping in the first survey was not associated with subsequent smoking, which suggests the overall correlation does not reflect regular vapers who progress to cigarettes after getting hooked on nicotine. Just 21 students--0.2 percent of the sample--initially reported that they had never smoked but had vaped during the previous month and...