By Reuters Staff

CHICAGO (Reuters) - Overall tobacco use among U.S. middle and high school students has not changed since 2011, a period in which use of electronic cigarettes increased dramatically, U.S. health officials said on Thursday.

Given that most adult smokers begin using tobacco before age 20, health officials are concerned over the lack of progress in reducing tobacco use among U.S. youth.

According to the latest data from the U.S. Centers for Disease Control and Prevention and the U.S. Food and Drug Administration's Center for Tobacco Products, 3 million middle and high school students reported using e-cigarettes in 2015, compared with 2.46 million in 2014.

"E-cigarettes are now the most commonly used tobacco product among youth, and use continues to climb," CDC Director Dr. Tom Frieden said in a statement.

"No form of youth tobacco use is safe. Nicotine is an addictive drug and use during adolescence may cause lasting harm to brain development."

The FDA, which currently regulates most conventional tobacco products, is finalizing regulations that would bring e-cigarettes under its authority.

Mitch Zeller, of the FDA's Center for Tobacco Products, said the agency "remains deeply concerned" about the overall high rate of tobacco use among youth and said finalizing those regulations "is one of FDA's highest priorities."

Increases in e-cigarette use in 2015 were largely driven by higher use among middle school students, a group in which use of the devices climbed to 5.3% in 2015 from 3.9% in 2014. There was no change in e-cigarette use among high school students between 2014 and 2015, following a dramatic 13.4% increase in 2014.

Overall, data from the 2015 survey show that 4.7 million middle and high school students used at least one tobacco product in the past 30 days, and more than 2.3 million of those students used two or more tobacco products.

There was no significant change in cigarette smoking habits among middle and high school students between 2014 and 2015, with 9.3% of high school students and 2.3% of middle school students saying they smoked cigarettes.

"Given that the use of e-cigarettes is on the rise among middle and high school students and nicotine exposure from any source is dangerous for youths, it is critical that comprehensive tobacco control and prevention strategies for youths address all tobacco products and not just cigarettes," study authors wrote in the CDC's weekly Morbidity and Mortality report.