When you stop smoking

After 20 minutes your blood pressure returns to normal. After 8 hours the levels of carbon monoxide in your blood are halved After 24 hours your lungs start to clear out debris. After 1-3 months lung function will improve by up to one third. After 5 years your risk of lung cancer will be halved. After 10 years your risk of all smoking related cancers will have reduced to almost normal levels. Even more reasons to quit smoking and less to start.