E-cigarettes and smoking hookah have gained popularity among middle and high school students in the U.S., according to the Centers for Disease Control and Prevention.

The number of middle and high school students using e-cigarettes tripled from 2013 to 2014.

Among high school students, 13.4 percent were found to be using e-cigarettes in 2014 compared with 4.5 percent in 2013. The number of middle school students using e-cigarettes also tripled from 1.1 percent in 2013 to 3.9 percent in 2014.

Vince Willmore, vice president for communication at the Campaign for Tobacco Free Kids, said marketing of e-cigarettes has played a big role in young people using the product.

“They’re available in flavors that appeal to kids like cotton candy and gummy bear, so it’s not surprising that kids are using more of these products because they’re being marketed in the very same way that regular cigarettes have been marketed to kids,” he said.

In 2014, former Gov. Steve Beshear signed a law banning the sale of e-cigarettes to minors in Kentucky.

Smoking among young people has long been prevalent in Kentucky. In 2012, an estimated 24.1 percent of high school students were smokers, according to United Health Foundation.

CDC’s findings also show the number of middle and high school students smoking hookah nearly doubled.

Among high school students, 9.4 percent were found to be smoking hookah in 2014 compared with 5.2 percent in 2013. The number of middle school students smoking hookah also doubled from 1.1 percent in 2013 to 2.5 percent in 2014.

Willmore said smoking hookah has become a social activity for some young people.

“There’s a perception that hookah smoking is not as harmful as regular smoking, but the evidence shows that it is very harmful,” Willmore said.

Currently, e-cigarettes and hookah are not regulated by the U.S. Food and Drug Administration.

The government agency has issued a proposed rule that would extend its authority to cover additional products that meet the legal definition of a tobacco product, according to the FDA.

“We so desperately need the Food and Drug Administration to regulate e-cigarettes to prevent marketing and sales to kids, and the use of flavors that appeal to kids,” Willmore said.

E-cigarette use among youth now surpasses use of every other tobacco product overall, including conventional cigarettes, according to the data.

CDC says 24.6 percent of high school and 7.7 percent of middle school students were found to be using some type of tobacco product. There was no decline in overall tobacco use between 2011 and 2014.

The CDC and FDA’s Centers for Tobacco Products used data from the 2014 National Youth Tobacco Survey.