The Food and Drug Administration on Friday authorized the first menthol-flavored electronic cigarettes for adult smokers, the government’s strongest indication yet that vaping flavors can reduce the harms of traditional tobacco smoking.

The FDA said it authorized four menthol e-cigarettes from NJOY, the vaping brand recently acquired by tobacco giant Altria, which also makes Marlboro cigarettes.

Impact on Anti-Tobacco Advocacy

The decision lends new credibility to vaping companies’ longstanding argument that their products can help blunt the toll of smoking, which is blamed for 480,000 U.S. deaths annually due to cancer, lung disease and heart disease.

But parent groups and anti-tobacco advocates are certain to be disappointed by the decision after years of pushing against the availability of flavors like menthol, which are more popular with teens.

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Previous FDA Authorizations and Future Plans

All the e-cigarettes previously authorized by the FDA have been tobacco flavored, which isn’t widely used by young people who vape.

Altria’s data showed NJOY e-cigarettes helped smokers reduce their exposure to the harmful chemicals in traditional cigarettes, the FDA said. The agency stressed the products are neither safe nor “FDA approved,” and that people who don’t smoke shouldn’t use them.

Friday’s action is part of a sweeping FDA review intended to bring scientific scrutiny to the multibillion-dollar vaping market after years of regulatory delays. Currently the U.S. market includes thousands of fruit and candy flavored vapes that are technically illegal but have gone unregulated.

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The FDA faces a court deadline at the end of this month to wrap up its yearslong review of major vaping brands, including rivals like Juul and Vuse.

All of those brands have been sold in the U.S. for years, awaiting FDA action on their scientific applications. To stay on the market, companies must show that their products provide an overall health benefit for smokers, without significantly appealing to kids.

“Based upon our rigorous scientific review, in this instance, the strength of evidence of benefits to adult smokers from completely switching to a less harmful product was sufficient to outweigh the risks to youth,” said Matthew Farrelly of FDA’s Center for Tobacco Products.