Mint is the No. 1 choice for teens who vape nicotine, according to research published Tuesday in the Journal of the American Medical Association.

The findings come as the Trump administration weighs whether to include mint and menthol in an e-cigarette flavor ban that health officials proposed in September. A final decision is expected in the coming days or weeks.

The new research from the University of Southern California reveals that it's the mint flavoring that's most attractive to the young people whom federal health officials say they're trying to protect.

The study looked at responses from the 2019 Monitoring the Future survey, an annual report of more than 14,000 eighth, 10th and 12th grade students. Released in September, it showed that the number of kids vaping nicotine has doubled in the past two years.

The new analysis from USC focused on 1,739 students who said they used Juul products. The company — which accounts for the vast majority of e-cigarette sales — recently stopped selling most flavors, but still offers mint and menthol online.

When teens were asked which Juul flavors they used most often, the answer, by far, was mint, the study found.

Forty-seven percent of high school seniors and 44 percent of high school sophomores said they preferred mint. Mango was most popular among the surveyed middle school students, but mint was a close second.

"We need to continue to understand what products kids are using," said Jessica Barrington-Trimis, the study's author and an assistant professor of preventive medicine at the University of Southern California.

"Given the findings, if mint is exempt from these proposed policies, I don't know that it will do much" to curb youth vaping, she said.

The research comes during a time when the nation is grappling with a growing epidemic of severe lung illnesses linked to vaping. The Centers for Disease Control and Prevention said 1,888 people have been sickened, many of whom had to be hospitalized in intensive care units. Thirty-seven people have died, including one teenager.

Investigators have been unable to pinpoint any single product or ingredient that's to blame. Most patients said they had vaped THC, the psychoactive ingredient in marijuana. But some said they only vaped products containing nicotine. Juul products have not been linked to the illnesses.

Easier to inhale, harder to quit

Vaping advocates say that e-cigarettes, especially those flavored with menthol, can help longtime cigarette smokers quit.

Experts who study the history of tobacco dismiss that argument.

"There's not one study ever that has shown that using mint and menthol e-cigarettes is going to help you get off combustible cigarettes," said Phillip Gardiner, the policy and regulatory sciences program officer for the Tobacco-Related Disease Research Program at the University of California.

On the contrary, studies show menthol makes it easier to inhale more tobacco, paving the way to addiction.

"Just like when you rub a product that uses menthol like Bengay or Vick's VapoRub on your leg to reduce pain, menthol reduces the pain of inhaling nicotine," said Pebbles Fagan, director of the Center for the Study of Tobacco at the University of Arkansas for Medical Sciences, Fay W. Boozman College of Public Health.

"It produces a cooling sensation in the throat," she said.

Gardiner added that menthol allows for deeper inhalation. "The deeper you inhale, the more toxins and nicotine you take in. The more toxins and nicotine you take in, the more addicted you become," Gardiner said.

"Menthol is the ultimate candy flavor: It helps the poison go down easier."

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