“E-cigarettes are 95% less harmful than tobacco and could be prescribed on the NHS in future to help smokers quit,” BBC News reports.
Most e-cigarettes contain a battery, an atomiser and a replaceable cartridge. The cartridge contains nicotine in a solution of either propylene glycol or glycerine and water, and sometimes flavourings.
When you suck on the device, a sensor detects the air flow and starts a process to heat the liquid inside the cartridge, so it evaporates to form water vapour. Inhaling this vapour delivers a hit of nicotine straight to your lungs.
Unlike “traditional” cigarettes, they do not contain the many dangerous chemicals that can increase the risk of lung cancer, heart disease and stroke.