Fruit- or candy-flavoured electronic cigarettes may entice American teens to start smoking tobacco, a new study suggests.
Using data from the 2014 National Youth Tobacco Survey, researchers at the University of Missouri-Kansas City found that among middle school and high school students who had never smoked, 58 percent who used flavoured e-cigarettes said they intended to start smoking tobacco cigarettes.
"Due to a proliferation of e-cigarette flavours on the market, flavoured e-cigarette use among youth in the US has increased significantly," study author Hongying Dai said. She's an associate professor of health services and outcomes at Children's Mercy Hospital in Kansas City.
"The majority of youth who have ever used e-cigarettes started with a flavoured product," Dai added.
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Flavoured e-cigarettes aren't prohibited in the United States. More than 460 brands and 7,700 flavours are currently on the market. The number of teens who use e-cigarette devices to "vape" has nearly quadrupled since 2013, Dai said.
The recent rule from the US Food and Drug Administration regulating e-cigarettes excluded the agency from regulating flavours in these products. This provision was deleted from the original FDA proposal by the White House Office of Management and Budget.
Perception of dangers
"Flavoured e-cigarette use among youth might serve as a gateway for future smoking and was associated with decreased odds of quitting smoking," Dai said. "Comprehensive tobacco control and prevention strategies that address flavoured e-cigarette products are critically needed to reduce tobacco use among youth."
Among nearly 16,500 teens who had never smoked cigarettes but used e-cigarettes, Dai's team looked at whether or not they intended to begin smoking tobacco cigarettes. The researchers also looked at more than 1,300 current smokers and assessed if they intended to quit. Finally, the investigators looked at nearly 21,500 teens to assess their perception of the dangers of tobacco.
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The study found that just over 2,000 teens said they had used e-cigarettes in the last 30 days. Of these, 61 percent said they had used flavoured e-cigarettes. Among those who had never smoked traditional tobacco, 56 percent of e-cigarette users said they had used flavoured e-cigarettes. Among current tobacco smokers, 68 percent of those who also "vaped" said they had used flavoured e-cigarettes.
A majority of kids who used flavoured e-cigarettes but had never smoked tobacco said they were likely to smoke tobacco cigarettes in the future. In addition, tobacco smokers who also used e-cigarettes said they were less likely to quit smoking. Moreover, e-cigarette use was associated with a lower perception of the harmful effects of tobacco, Dai said.
A spokesman for the e-cigarette industry didn't address these findings directly. Instead, he took issue with the study's design.
Public worse off
"In this study, any teen who answered 'probably not' when asked if he or she thought they would smoke a cigarette in the next year was marked as 'intending to smoke', " said Gregory Conley, a spokesman for the American Vaping Association.
Only a small number of participants answered "definitely" to the cigarette smoking question, Conley said. "So in order to give themselves statistical power, the researchers enlarge the category to include 'probably not', " he said.
"This is a classic example of the peer-review process failing and the public being worse off as a result," he said.
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At least one expert on smoking issues disagreed with Conley's assessment of the new research.
"This is an important paper that shows how e-cigarette flavours are expanding the tobacco epidemic, particularly their important role in stimulating youth use of e-cigs and progression to smoking conventional cigarettes," said Stanton Glantz. He's a professor of tobacco control at the University of California, San Francisco.
Even if kids don't start smoking conventional cigarettes, expanding the use of e-cigarettes among kids is itself dangerous, Glantz said.
"This reality makes the fact that the Obama White House dropped regulation of flavours, which especially appeal to kids, from the FDA's recent rule taking jurisdiction over e-cigarettes worrisome," Glantz said. "The effect of this deletion will delay regulation of flavours in e-cigarettes by years, leading more kids to get addicted to nicotine," he said.
The new report was published online in the journal Paediatrics.
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