You've heard the risks associated with smoking cigarettes since the early years of elementary school.

Smoking can cause cancer, health complications and death.

Even though overall smoking prevalence has declined from 20.9 percent in 2005 to 18.1 percent in 2012, that's still a lot of people who smoke. According to the Centers for Disease Control and Prevention, an estimated 42.1 million people ages 18 and older in the U.S. smoke cigarettes.

What about the use of electronic cigarettes?

An electronic cigarette is a cigarette-shaped device containing a nicotine-based liquid that is vaporized and inhaled. This method is used to stimulate the experience of smoking tobacco.

E-cigs have claimed to be safer for smokers and for non-smokers who might have previously inhaled secondhand smoke.

Benefits of these e-cigs are that they don't contain the carcinogens, tobacco, herbicides, pesticides or the arsenic from tobacco smoke. However, they do have compounds such as di-ethylene glycol, an ingredient used in antifreeze.

Are they truly healthier?

Dr. Holly discusses what electronic cigarettes are, how they came about, and if the e-cig benefits outweigh the risks.