It’s a commonly held belief that longevity is closely associated with genetics; if your parents and grandparents lived well into very old age, you have a better than average chance of doing the same. However, more recent research has found that our lifestyle rather than family history may have more to do with how long we will live.
A new large-scale study, published in the journal Genetics, has determined that genetics only account for about 7 percent of the many factors that contribute to longevity. Although long life does tend to run in families, researchers from Calico Life Sciences and Ancestry discovered that previous longevity studies did not take into account the tendency people have to choose mates that have traits similar to their own.
Using the data of 54 million Ancestry public family trees, researchers factored the tendency for people to marry partners with similar lifestyles and sociocultural backgrounds into how longevity is estimated. People who are wealthy, tend to partner with other wealthy individuals for example, and taller people often prefer to marry someone who is also tall. If any of these preferred traits affect longevity, it follows that similar life spans between spouses may have skewed previous estimates of the hereditary aspects longevity, according to a Genetics Society of America press release.
Past longevity studies have estimated that human lifespan heritability is anywhere between 15 to 30 percent, but this new research drops the estimate to no more than 7 percent and perhaps even lower by taking into account “assortative mating”.
The upshot of this new information? Our lifestyle choices; what we eat, how much exercise we get or our exposure to risk for accidents may play a much bigger role in how long we live than our genetics.