According to a longer-than-ever-term study published in the British Medical Journal, smoking takes away 10 years of life of an average smoker. Quitting, on the other hand, gives huge benefits.
Quitting at 30, almost completely, eliminates the risk from dying prematurely, and giving up at 50 halves it. But half of those who fail to kick the habit will die as a result of smoking, and a quarter of all smokers die in middle-age.
The results come from a 50-year update of the famous 1954 paper which first linked smoking with lung cancer. One author of the update is Oxford University epidemiologist Richard Doll, now 91, who was a co-author of the original paper.
By following the fate of the original 34,439 male British doctors recruited for the study in the 1950s, the update has yielded fresh insights into how smoking affects survival to middle age and beyond.
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