If you quit smoking

An ashtray with lots of cigarette butts in it.
If you stopped smoking this minute, this is what will happen:
In 20 minutes time, at
Your blood pressure is dropping
Your pulse rate is coming down to normal
Your hands and feet are coming back to normal temperature
Later on, by
The carbon monoxide poison levels in your blood are dropping to normal
The oxygen levels in your blood have risen to normal
Tomorrow
your chances of a heart attack are starting to go down
By
you're starting to smell and taste things you couldn't before
On
your breathing is getting easier as your bronchial (lung) tubes relax
your lungs start taking in more oxygen
After 3 months, by
Your blood is moving round your body quicker and better
Your lungs are working 30% better than they were
Between and
You've stopped coughing
You're not feeling so tired
Your nose and throat aren't blocked up any more
You're not so out of breath
The lining of your lungs is regrowing normally
You've got lots more energy
If you're a bloke - your 'parts' like your penis are starting to work better (joy)
You've cut your chances of death from lung cancer by 50%
Your chances of getting heart disease have significantly decreased
Your chances of death from lung cancer are almost the same as a non-smokers
All your pre-cancerous cells have been replaced
Risk of other cancers (mouth, throat, bladder, kidney, cervix) all goes down as well