Switching from smoking to vaping dramatically reduces cancer risk Dr Colin Mendelsohn Dual cigarette and e cig use increases human risk of lung cancer 40 times Stanton Glantz blog E Cigarettes: Know the Health Risks Department of Health Rethinking Vaping Adolescents and E cigarette Use: Long term Effects, Behaviors and Lung Injury What chemicals are in a cigarette? What does smoking do to your body? Cancer Research UK