If you're young and start "vaping," you could start puffing for real—and real soon.
Young people who use electronic cigarettes are much more likely to begin smoking traditional tobacco cigarettes within a year than others their age who don't use e-cigs, according to a study released Tuesday.
The analysis, due to be published in the November issue of JAMA Pediatrics, is the third in recent weeks to raise questions about whether the increasingly popular e-cigarettes present potential health pitfalls for young users even as their advocates tout them as a healthier alternative to cancer-causing tobacco cigarettes.
One of those other studies found that almost 20 percent of Connecticut high school students who had used e-cigs also used them to vaporize marijuana or related substances.
The studies also come as the U.S. Food and Drug Administration is weighing how to regulate the battery-powered liquid nicotine vaporizers for the first time, and as major tobacco companies fight for market share in the burgeoning e-cig retail space. The chief executive of tobacco giant Philip Morris International, Andre Calantzopoulos, told CNBC earlier this week that he wants their lines of e-cigarettes eventually to outsell traditional cigarettes.
The latest study was conducted by the University of Pittsburgh Center for Research on Media, Technology and Health, and the Dartmouth-Hitchcock Norris Cotton Cancer Center, and funded by the National Cancer Institute.
Researchers looked at a national sample of almost 700 nontobacco smokers ages 16 to 26. Those people had all responded "definitely no" when asked if they would smoke a traditional tobacco cigarette offered by a friend, or if they thought they would use such a cigarette within the year. Because of those answers, the sample was considered "nonsusceptible" to traditional smoking.
The sample included some young people who smoked electronic cigarettes and others who did not.
By the next year, 38 percent of the e-cig users had started smoking traditional cigarettes, according to the study. Just 10 percent of the young people who didn't use e-cigs had started smoking tobacco cigarettes, researchers found.
"The differences remained statistically significant and robust even when we controlled for multiple known risk factors for initiating cigarette smoking, such as age, sex, race, ethnicity, socio-economic status, sensation seeking, parental smoking and friend smoking," said Dr. Brian Primack, lead author of the study.
Primack and study co-author Dr. James Sargent offered several theories in their analysis about why e-cigarettes could be a gateway device to tobacco cigarettes.
One theory is that the e-cigs deliver nicotine slower than traditional cigarettes, which allows an e-cig users to become more tolerant of nicotine's side effects and progress to tobacco.
Primack and Sargent speculated that because e-cigarettes mimic the behavioral and sensory sensation of traditional smoking, the user is more accustomed to the practice of using traditional cigarettes. And they suggested that smoking, which has become increasingly banned in a variety of settings in recent decades, may have become somewhat "renormalized" by electronic cigarettes.
Sargent pointed out that electronic cigarettes can be marketed on television, unlike cigarettes, which had been banned from TV ads for more than four decades.
Sargent said the study should serve as a warning for policymakers at a time when "more youth than ever are using e-cigarettes and that as many as half of these adolescents are not smoking traditional cigarettes."
"It is important to continue surveillance of both e-cigarettes and tobacco products among young people so policymakers can establish research-informed regulations to help prevent e-cigarettes from becoming gateway products on the road to youth smoking," Sargent said.
Primack noted that e-cigs currently aren't subject to many of the laws that regulate traditional cigarettes, such as age limits and taxes, and that "they also come in youth-oriented flavorings ... such as apple bubble gum and chocolate candy cane" that are barred for regular smokes.
The study comes less than a month after another one in the Journal of American Medical Association also suggested that e-cigs could serve as a gateway to traditional tobacco for young users.
In that study, which looked at about 2,500 high school students in Los Angeles, 31 percent of e-cig users said they had ended up using combustible tobacco products, including cigarettes, cigars and hookah pipes, in the following six months, compared with just 8 percent of students who had never used e-cigs before.
The third study, released earlier this week in the journal Pediatrics, focused on youth and e-cig use. It surveyed more than 3,800 students at five high schools in Connecticut.
Researches from Yale University found that almost 28 percent of the students had reported using e-cigs. Of those users, almost 19 percent said they had used the devices to vaporize pot or related substances that contain THC, the psychoactive ingredient in marijuana.
"This is a relatively novel way of using marijuana, and kids are using it at a fairly high rate," said Meghan Morean, lead author of the report.
Morean suggested that e-cigs offer kids a discrete ways of using pot.
"The smell of vaping marijuana isn't as strong as smoking it, plus the similarity in appearance of hash oil and nicotine solutions make this a really inconspicuous way of using marijuana," Morean said.
She also said that liquid forms of marijuana can be significantly more potent than dried marijuana leaves.