cigarette smoke chemical composition characterization and health risks associated with e-cigarettes: A comprehensive review The main chemical component of

Nicotine has been shown to stimulate the release of dopamine, a neurotransmitter associated with pleasure and happiness

While our conclusions are limited because there arent many high quality studies available yet, overall the evidence suggests that (1) e-cigarettes with nicotine can help people quit smoking, (2) they dont seem to have any serious side effects in the short- to mid- term (up to 2 years), and (3) in some cases, switching to them leads to changes in your blood and breath that are consistent with the changes youd see in people who give up smoking altogether

In fact, according to recent data, its the second most common cancer among men worldwide

Findings from the International Tobacco Control (ITC) Four Country Survey"