We all know one: an aunt, a great-grandfather, an in-law who flies in the face of common health wisdom and who, despite smoking regularly for decades, shows no sign of slowing down. Turns out, there may be a genetic reason for their resilience—a new study suggests that smokers who live longer-than-average lives may be predisposed to survival.
In a paper published this week in The Journals of Gerontology, Series A: Biological Sciences & Medical Sciences, a team from the University of California, Los Angeles, compared 90 smokers who lived past 80 to more than 700 smokers between ages 50 and 70. As study author Morgan E. Levine told Quartz, the latter group represents the average smoker, who has a relatively short lifespan—about 10 years less than a non-smoker, on average.
After analyzing about 1.2 million gene markers, researchers found that a few thousand significantly correlated with longer life among the smokers, explained Levine. From there they asked, which of these longevity genes interact with each other? The resulting discovery was a 215-gene network that seemed to represent resilience in smokers.
Then, the researchers looked for that gene network in over 6400 nonsmokers.
They found that nonsmokers who had that same gene network were 22% more likely than average to live into their 90s and 300% more likely to live past 100. Cancer was also 11% less likely among nonsmokers with the network.
In other words, this genetic variation isn’t just one that keeps the harmful effects of smoking at bay, but that one that may encourage overall longevity.
Though the sample size is small, the team believes that its research will aid in a better understanding of what promotes long life in the general population.
Since long-lived outliers are extremely rare, Levine told The Washington Post, “Nobody should use this paper as an excuse to continue smoking.” Cautions Levine, “Even among those who are genetically predisposed to longevity, smoking cessation is likely still one of the best things they can do for their health.”
Image by Alcino on Flickr, licensed under CC BY-SA 2.0.