If you want to increase your risk of multiple diseases, then smoking is one of surest ways to do it; it can even accelerate aging. So how do some long-term smokers beat the odds?
Long-lived smokers are fascinating. Not only do they live a long time, but they also appear unaffected by their habit. For most of us, smoking has been confirmed to be 'toxic', but these outliers somehow overcome this. So how can these people reach old age despite having smoked most of their life? Scientists predicted they must have some unusual genes, and they were right.
New research suggests this longevity isn't mere coincidence. The study compared 90 smokers who lived over 80 to 720 who died before reaching 70. They found that these individuals have particular changes in their DNA called single nucleotide polymorphisms (SNPs). This means that one letter in the code is switched for another. These SNPs are common but don't confer any benefit if they're in a non-coding region (probably). Forensic scientists can identify a person by this unique signature.
Where were these changes?
Scientists found this hardy group had these SNPs in a special network of genes known to give anti-aging benefits. This network is associated with a 22% increase in likelihood of reaching 90, lowers cancer by 11%, and boosts chances of making it past 100 3 times over.
“There is evidence that these genes may facilitate lifespan extension by increasing cellular maintenance and repair. Therefore, even though some individuals are exposed to high levels of biological stressors, like those found in cigarette smoke, their bodies may be better set up to cope with and repair the damage.”
This is a rare bunch of people
This innate resistance is extremely rare, and for the majority of people smoking is ill-advised. Even if your family has a history of longevity, there's no guarantee you've inherited the same gifts. These genes may well offer protection, but if these people didn't smoke, could they live even longer?
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