Let's understand the principle,
Why are cigarettes so harmful that they can blacken your lungs?
Because the tobacco of cigarettes has a combustion process, during which 69 carcinogens such as tar and carbon monoxide will be produced. We often see black spots on the lungs of old smokers. In fact, it is caused by tar deposition.
Tobacco burning also produces tobacco specific nitrosamines, which can be said to be the chief culprit of tobacco harm. It is a first-class carcinogen identified by the World Health Organization and is directly related to lung cancer. However, e-cigarettes do not have the combustion process of tobacco, so they will not produce these hazards. It's better to look at the official information than to believe these chaotic we media rumors.
According to the official website of the British government, the British office for health improvement and difference (ohid) has updated the smoking cessation guide for doctors. In the chapter on smoking cessation assistance, the harm reduction and smoking cessation potential of e-cigarettes are specially emphasized. At the same time, the guide also points out that nicotine is only an addictive substance, not carcinogenic.