In spite of serious warnings about the possible health risks of vaping, more and more American teenagers are getting hooked on e-cigarettes.

Experts believe this is because young people are attracted to the flavored nicotine liquid used by manufacturers, such as menthol, pomegranate, cappuccino and single-malt scotch.

A recent study funded by the National Institutes of Health (NIH) explored the possible connection between the appeal smoking e-cigarettes and the growing number of youngsters who engage in vaping.

Suchitra Krishnan-Sarin, professor of psychiatry at the Yale School of Medicine, led a team of researchers studying the methods that lure people to smoke e-cigarettes. They conducted a survey 5,400 Connecticut teens to find out what is "cool about e-cigarettes."

The top answers given by the participants? The different flavors of nicotine liquids and being able to do tricks with e-cigarettes.

"We expected the flavors were attractive," Krishnan-Sarin said. "But smoke tricks were a surprise to us."

Electronic devices – such as the ones used for vaping – produce more vapor than the smoke regular cigarettes give off. E-cigarettes can be adjusted to generate more heat in order to make vapor tricks possible. Many teenagers utilize that function to engage in "cloud competitions," which make e-cigarettes more appealing.

In 2014, the Centers for Disease Control and Prevention (CDC) reported that the number of American teenagers and preteenagers who smoke e-cigarettes had increased significantly, to 13.4 percent from the 4.5 percent of the previous year.

By contrast, overall tobacco use across the country decreased to 9.2 percent from 12.7 percent during the same period.

The CDC data prompted public health advocates to draft a petition requesting the Obama administration to finalize the proposed guidelines that will authorize the Food and Drug Administration to regulate the use and sale of e-cigarettes.

While vaping is believed to be less risky than smoking conventional cigarettes, research shows that the vapor from e-cigarettes contains nitrosamines, carbonyls, volatile organic compounds and heavy metals — four chemical compounds that are toxic and carcinogenic.

There are numerous Youtube videos of people doing smoke tricks with e-cigarettes, such as these clips from Michael Lammers, Junior García and Michał Jag. Demonstrating awareness of both the dangers and "coolness" of vaping, Michael Lammer explains how to pull a "ghost," inhaling so "basically no smoke comes out — it all goes into your lungs. It's kind of unhealthy... but it does get you buzzed and or high."

The Yale School of Medicine study is published in the journal Nicotine and Tobacco Research.

Photo: Lauri Rantala | Flickr