E cigarettes: Mounting evidence shows the dangers of these new age devices School of Public Health Most e cigarettes contain nicotine, which is highly addictive. Putting maximum limits on the nicotine strength of e cigarettes, along with evidence based tobacco control strategies, may help reduce youth e cigarette use and increase quitting Evidence strengthens that vaping is effective for stopping smoking but not reaching its full potential with adult smokers King's College London That big claim that vaping leads to smoking may be based on insubstantial evidence Public Health Consequences of E Cigarettes