Thanks to years of research, the links between smoking and cancer are now very clear. Smoking is the single biggest cause of cancer in the world, and accounts for one in four UK cancer deaths.

Which cancers are caused by smoking?

Smoking causes nine in ten cases of lung cancer. Lung cancer has one of the lowest survival rates of all cancers, and is the most common cause of cancer death in the UK. The good news is that most of these deaths are preventable, by giving up smoking in time.

Smoking also increases the risk of over a dozen other cancers including cancers of the mouth, larynx (voice box), oesophagus (food pipe), liver, pancreas, stomach, kidney, bladder and cervix, as well as some types of leukaemia.

How does smoking cause cancer?

Tobacco smoke contains at least 80 different cancer-causing substances. When you inhale smoke, these chemicals enter your lungs and spread around the rest of your body.

Scientists have shown that these chemicals can damage DNA and change important genes. This causes cancer by making your cells grow and multiply out of control.