[...] researchers found that in 2014 people age 12 to 24 who used e-cigarettes were three times as likely to become daily cigarette smokers in the future. Among those who reported using a tobacco product, daily use increased with age through age 28. Daily cigarette smoking nearly doubled between 18 to 21 year olds (12 percent) and 25 to 28 year olds (21 percent).
"This is the first paper that actually looks at progression to dependent cigarette smoking among young adults. In these data, e-cigarettes are a gateway for those who become daily cigarette smokers," said the study's first author, John P. Pierce, [...]