Electronic cigarettes may be more tempting to nonsmoking youths than conventional cigarettes, and once young people have tried e-cigarettes they are more inclined to give regular cigarettes a try, U.S. researchers said Monday.

A report, released by a team at the U.S. Centers for Disease Control and Prevention, lends evidence to the argument that electronic cigarettes encourage youth smoking.

The study, based on nationally representative youth surveys, found that more than a quarter-million adolescents and teens who had never smoked used an electronic cigarette in 2013, a threefold increase from 2011.