Jiyoon Park

A new Yale study shows that e-cigarette flavors may contribute to increased usage in adolescent populations.

Researchers at the School of Medicine have discovered that e-cigarette flavors differently affect patterns of e-cigarette usage between adolescent and adult populations. These findings provide researchers with a greater understanding of the consequences of the availability of a wide range of e-cigarette flavors. The study was published in the journal PLOS ONE on Jan. 4.

“Flavor preferences uniquely were associated with using e-cigarettes more frequently among youth,” said Meghan Morean GRD ’11, the study’s lead author. “Specifically, the total number of flavors youth preferred and their preferences for flavors including fruit, dessert and alcohol were associated with using e-cigarettes more frequently.”

According to an article by the Centers for Disease Control and Prevention, the portion of students using e-cigarettes dropped from 2015 to 2016, but the more recent levels are still several times higher than those from 2011–13. Popular e-cigarettes include the JUUL, XEO VOID and EX Series.

“E-cigarettes are available in over 7000 flavors, which seem to enhance the appeal of these products, especially to youth,” said Suchrita Krishnan-Sarin, professor of psychiatry and the study’s senior author. “We wanted to understand if preference for particular flavors as well as use of a large number of flavors was associated with frequency of e-cigarette use, and whether these relationships differed among youth and adults.”

The researchers analyzed two separate cohorts of people: high school students from Connecticut and adults from an online survey platform. In this setup, the adults were used as a comparison sample to the adolescents, who were given a survey at their high schools.

According to Morean, the study found that “adolescents generally were more likely to prefer traditionally sweeter flavors like fruit while adults were more likely to prefer flavors that would not be classified as sweet, including flavors that are associated with traditional cigarettes like tobacco and menthol.”

According to the study, the most popular flavors among adolescents included fruit, dessert and vanilla.

Additionally, the researchers found that while the number of flavors used by adolescents was associated with frequent use, this pattern did not hold true in the adult sample.

One potential limitation to the study was the use of self-reporting, Morean said. “Most research depends on self-report. People could be trying to deceive you, though there wasn’t any evidence of that in this study,” she added.

Morean emphasized that the study was preliminary by nature. As a cross-sectional project, the study looked at e-cigarette usage at a specific point in time. A more comprehensive study, Morean said, would be longitudinal, in which individuals’ e-cigarette usages are followed temporally.

“It is important to note that this is just a jumping-off point; additional longitudinal research, ideally conducted with nationally representative samples, is needed before any conclusions can be drawn,” she said.

Krishnan-Sarin said scientists must also perform studies that connect flavors to efforts to quit cigarettes or other combustible tobacco products. For example, she said, adults trying to quit smoking may prefer menthol-flavored e-cigarettes.

Both authors are cautiously optimistic about the regulatory implications that their study provides.

“Our study provides initial evidence that suggest that regulating flavors in e-cigarettes may be more important for preventing initiation of use among youth,” Krishnan-Sarin said.

Morean added that the Federal Drug Administration was interested in studies similar to theirs given the FDA’s regulatory authority. While cigarettes have been heavily regulated, e-cigarettes have not. The FDA is still in the process of gathering scientific evidence to support their decisions, she said.

“If this line of work pans out, it provides evidence that sweet types of flavors might be regulated to protect kids, but it is too early to make that claim,” she said.

On Sept. 22, 2009, the FDA banned cigarettes of all flavors except tobacco or menthol under the Family Smoking Prevention and Tobacco Control Act.

Vikram Shaw | vikram.shaw@yale.edu