Action on Smoking and Health (ASH) is a campaigning public health charity that works to eliminate the harm caused by tobacco. ASH does not attack smokers or condemn smoking.
There are a host of interesting and useful factsheets on the site on smoking and tobacco, including factsheets on young people and smoking, how smoking affects the way you look, shisha, e-cigarettes and support in quitting smoking.
Smoking harms nearly every organ of the body. It causes many diseases and reduces quality of life and life expectancy. The younger a person quits, the greater the benefit, but stopping smoking is beneficial at any age. Many smokers think that smoking helps relieve stress but in fact, ex-smokers are more likely to go on to have better mental health and be happier than they were before they quit. You can visit their website or read some factsheets regarding smoking and how to quit. There are also ASH Resources for schools.