In the 1970s, Sir Richard teamed up with protege Richard Peto and formed the Clinical Trial Service Unit at the University of Oxford. In the forty-year follow-up to the Physicians Health Study they observed that about half of smokers who do not quit die prematurely.

“Results from the first 20 years of this study, and of other studies at that time, substantially underestimated the hazards of long term use of tobacco. It now seems that about half of all regular cigarette smokers will eventually be killed by their habit.”

“Even in middle age stopping smoking substantially increased the subsequent expectation of life - and those who stopped before 35 years of age had an expectation of life that was not significantly different from that of non-smokers.”