The national discussion about the health risks of vaping involves both the long-term effects of e-cigarettes and an immediate crisis. Earlier this month, 380 lung disease cases in 36 states, along with seven deaths, had been linked to vaping. It appears from news reports that many of those cases involve vaping not a nicotine product but THC, the active ingredient in marijuana. Government agencies and medical researchers are still investigating.

Those cases serve as the backdrop for a movement both nationally and locally to crack down on vaping. This week, Chicago Mayor Lori Lightfoot proposed a citywide ban on the sale of flavored e-cigarettes. An alderman went further, pushing for a ban on all vaping products.

Earlier this month, President Donald Trump called for a nationwide ban on flavored e-cigarettes. Before Trump’s announcement, Michigan had issued an emergency directive banning flavored vaping products. Last week, New York’s state Public Health and Health Planning Council voted to ban the sale of flavored e-cigarettes and other vaping products except for menthol and tobacco flavors.

Smoking tobacco products is a dangerous habit. Cigarettes kill. Much less is understood about vaping’s effects. E-cigarettes, which are smokeless and don’t contain tobacco, generally produce fewer toxic chemicals than the deadly mix of 7,000 chemicals in smoke from regular cigarettes, according to the Centers for Disease Control and Prevention. The vaping industry says its products help people wean themselves from cigarettes. But does vaping, too, have long-term health risks? As of now, it’s vapers beware.

On one point, there is little debate. Robust efforts to keep teens from vaping make sense. Nearly a quarter of teens in a 2018 survey by the National Institute on Drug Abuse said they had vaped within the past month. That’s double the 2017 rate. And vaping can put teens on the path of a lifelong tobacco habit: According to a recent Journal of the American Medical Association study, youths 12 to 17 who vaped are twice as likely to become regular tobacco smokers within a year.

Many states have imposed age restrictions on purchasing e-cigarettes. In Illinois, as of July 1, it is illegal to sell vaping products to anyone under 21. Good.

But should Chicago’s City Hall now ban purchases by adults?

Products with known health risks — tobacco, alcohol and cannabis among them — are sold legally to American adults. Prohibition has a failed history in this country. Public education campaigns can help people understand the known and potential risks of vaping, in the same way that awareness campaigns have helped Americans understand the risks of tobacco use, and driving while impaired by alcohol or other drugs.

But it’s unwise for government officials to act on their own hunches about what’s best for adults who can make their own decisions. Adults who see e-cigarettes as the lesser of two evils should have the option to vape.

Is it smart for them to do so? The medical verdict on vaping isn’t in.