Young people who use e-cigarettes may be more likely to smoke cigarettes in the future...

Research Suggests Vaping Is Bad for Your Heart and Lungs.

Nicotine is the primary agent in both regular cigarettes and e-cigarettes, and it is highly addictive. It causes you to crave a smoke and suffer withdrawal symptoms if you ignore the craving. 

Nicotine is also a toxic substance. It raises your blood pressure and spikes your adrenaline, which increases your heart rate and the likelihood of having a heart attack.