FDA Commissioner Scott Gottlieb made an apt freeway comparison when he recently summed up a critical challenge before him — cracking down on e-cigarette use by teens.

Also known as “vaping,’’ e-cigarettes deliver a smokeless hit of addictive nicotine through small, sleekly designed cartridges. A rapid rise in use by high school students has escalated public health concerns even though hope remains that e-cigs could help longtime smokers of regular cigarettes kick the habit.

“In order to close the on-ramp for kids, we are going to have to narrow the off-ramp for adults,’’ Gottlieb said in a Politico interview earlier this month.

Gottlieb merits praise for pulling off that delicate balancing act with last week’s announcement that the U.S. Food and Drug Administration is moving quickly to ban sales of candy- and fruit-flavored vaping products in many retail settings, primarily gas stations and convenience stores. The action follows months of tough talk by Gottlieb, who made it clear that he is willing to wield the agency’s sweeping authority to keep products made by Juul and other e-cig manufacturers out of underage hands.

Though some retailers have acted responsibly, too many have failed to police sales to minors. Taking aim at sweet-flavored products is also logical. These are the ones most likely to appeal to young users. At the same time, tobacco, mint and menthol vaping products will still be available, providing options for those trying to quit smoking regular cigarettes.

Vaping is considered less harmful than smoking cigarettes but still isn’t a healthy habit. Research on nicotine’s effect on adolescent brains has fueled concerns about young users and e-cigarettes. There are also harmful chemicals in e-cig vapor. And as Gottlieb noted Thursday in a statement, “The data show that kids using e-cigarettes are going to be more likely to try combustible cigarettes later. This is a large pool of future risk.’’

Anti-smoking advocates question how the retail restrictions will be enforced, but the move nevertheless is a step forward. The sooner it takes effect, the better. Asked when the new restrictions will begin, an FDA spokesman declined to provide details to an editorial writer on Thursday but said, “Shortly.”

Regulation is also necessary even as e-cig companies have recently announced voluntary steps to reduce minors’ access. These begrudging efforts are nothing more than an attempt to head off FDA action. Firms that voluntarily enact protections can also just as easily shrug off this responsibility in the future.

The crackdown on flavored e-cigs shouldn’t overshadow another important step announced by the FDA to prevent younger generations from getting hooked on tobacco. As part of what the agency is calling its “tobacco framework plan,’’ officials are proposing a ban on menthol-flavored cigarettes and flavored cigars. It could take years to move these restrictions through the regulatory and rulemaking process, but launching this process is nevertheless a public health milestone.

Flavored tobacco products appeal to new users, and the popularity of menthol cigarettes in particular may exacerbate health disparities. “More than half (54 percent) of youth smokers ages 12-17 use menthol cigarettes, compared to less than one-third of smokers ages 35 and older,’’ Gottlieb’s statement said. “Prevalence of menthol use is even higher among African-American youth, with data showing that seven out of 10 African-American youth smokers select menthol cigarettes.”

Regrettably, the FDA backed away from a ban on menthol cigarettes during the Obama administration, even after an advisory committee detailed these products’ harm. Gottlieb should seize the opportunity to protect future generations’ health and push unwaveringly to right that error.