Chain smoker keeps his promise

I can remember visiting [my father] while he was dying from lung cancer aged 50. He made me promise to stop smoking. These were the first words he had ever uttered to me.

I promised I would and promptly lit up as soon as I left the hospital, so in thrall was I to my addiction."

Allen Carr was a chain smoker for 33 years but later on went from smoking 100 cigarettes a day to none.