Although e-cigarettes have been marketed as a way to help people quit smoking, a new study finds that teens who use the products often smoke regular cigarettes as well.
In 2011 and 2012, about 50 percent of the U.S. teens who had used e-cigarettes in the past month were also current smokers of regular cigarettes, meaning they had smoked at least 100 cigarettes in the past month, the study found.
Teens who had used e-cigarettes at least once were also more likely to have experimented with regular cigarettes (smoking at least a puff or two), compared with teens who had not used e-cigarettes. [Kick the Habit: 10 Scientific Quit-Smoking Tips]
Teens who used e-cigarettes were also less likely to quit smoking. Among those who had smoked at least 100 cigarettes in their lifetime, the odds of quitting smoking for 30 days were about 40 percent lower for those who had tried e-cigarettes than for those who didn't use e-cigarettes.
"These results suggest that e-cigarette use is aggravating, rather than ameliorating, the tobacco epidemic among youths," the researchers wrote in the March 6 issue of the journal JAMA Pediatrics.
E-cigarettes do not burn tobacco. Instead, they vaporize nicotine, which is then inhaled by the user. Although the products contain fewer toxins than traditional cigarettes, they still contain nicotine, which is a highly addictive substance, the researchers said.
Nicotine may also have permanent effects on the brain, and may cause difficulties with attention and memory, the researchers said. Teens may be particularly vulnerable to the effects of nicotine, they said.
The researchers also noted that e-cigarettes are being aggressively marketed, and come in flavors such as strawberry and chocolate, which are prohibited in conventional cigarettes.
Because the study was conducted at one point in time, it cannot determine which behavior the teens adopted first — e-cigarette use or regular smoking — so the researchers do not know whether e-cigarettes are a "gateway" to conventional smoking.
Still, the findings suggest "e-cigarettes may contribute to nicotine addiction and are unlikely to discourage conventional cigarette smoking among youths," the researchers said.
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