A new study in Addiction shows that smoking a single cigarette decreases life expectancy by an average of 20 minutes, reports CNN Health. The study is based off British smokers and was commissioned by the U.K. Department for Health and Social Care.
The research, which came out of University College London, estimated that the loss of life expectancy for men was about 17 minutes and for women was about 22 minutes.
According to Sarah Jackson, lead author of the paper and a principal research fellow in the UCL Alcohol and Tobacco Research Group, “20 cigarettes at 20 minutes per cigarette works out to be almost seven hours of life lost per pack.”
“The time they’re losing is time that they could be spending with their loved ones in fairly good health,” Jackson said. “With smoking, it doesn’t eat into the later period of your life that tends to be lived in poorer health. Rather, it seems to erode some relatively healthier section in the middle of life. So when we’re talking about loss of life expectancy, life expectancy would tend to be lived relatively good health.”
The research used mortality data from the British Doctors Study and the Million Women Study, showing that people who smoked throughout their lives lost, on average, around 10 years of life compared to nonsmokers. Life expectancy is similar in the U.S. for smokers versus nonsmokers, according to the U.S. Centers for Disease Control and Prevention.
The amount of life expectancy that can be recovered by quitting smoking can depend on several factors, according to the new research.
“In terms of regaining this life lost, it’s complicated,” said Jackson. “These studies have shown that people who quit at a very young age—so by their 20s or early 30s—tend to have a similar life expectancy to people who have never smoked. But as you get older, you progressively lose a little bit more that you can’t regain by quitting.
“But no matter how old you are when you quit, you will always have a longer life expectancy than if you had continued to smoke. So, in effect, while you may not be reversing the life lost already, you’re preventing further loss of life expectancy.”