In 2014, more teens use e-cigarettes than traditional, tobacco cigarettes or any other tobacco product — the first time a U. S.national study shows that teen use of e-cigarettes surpasses use of tobacco cigarettes.

These findings come from the University of Michigan's Monitoring the Future study, which tracks trends in substance use among students in 8th, 10th and 12th grades. Each year the national study, now in its 40th year, surveys 40,000 to 50,000 students in about 400 secondary schools throughout the United States.

"As one of the newest smoking-type products in recent years, e-cigarettes have made rapid inroads into the lives of American adolescents," said Richard Miech, a senior investigator of the study.

The survey asked students whether they had used an e-cigarette or a tobacco cigarette in the past 30 days. More than twice as many 8th- and 10th-graders reported using e-cigarettes as reported using tobacco cigarettes.

Specifically, 9 percent of 8th-graders reported using an e-cigarette in the past 30 days, while only 4 percent reported using a tobacco cigarette. In 10th grade, 16 percent reported using an e-cigarette and 7 percent reported using a tobacco cigarette.

Among 12th-graders, 17 percent reported e-cigarette use and 14 percent reported use of a tobacco cigarette. The older teens report less difference in use of e-cigarettes versus tobacco cigarettes.

Additional information is available at goo.gl/2tqIpv.