Researchers at the University of Edinburgh have conducted a large meta-analysis on the genes that lead to a longer life. They were able to quantify how certain genes and lifestyle choices contribute to months being added to, or taken away from, your lifespan.
The researchers, publishing in Nature Communications, analyzed the genetic information of over 606,000 people. They looked at specific genetic markers and the lifespans of the participants' parents. Since we all share our genetic ancestry with our parents, the team was able to pinpoint the impact of various genes on longevity.
“The power of big data and genetics allow us to compare the effect of different behaviours and diseases in terms of months and years of life lost or gained, and to distinguish between mere association and causal effect,” senior author Professor Jim Wilson said in a statement.
And this is where the lifestyle choices come in. The researchers had to take them into account to make sure they were independent of the genetic risks. But at the same time, they could compare people with similar risk factors to see how different behaviors changed their chances of a long life.
Unsurprisingly, staying in shape is positively correlated with living for a long time. So is having high levels of "good" cholesterol. Meanwhile, smoking, heart problems, diabetes, and being overweight all reduce your lifespan. Every unit over the normal BMI value is equivalent to 7 fewer months of life. However, it’s not all doom and gloom. Smokers who quit can reach, over time, the same lifespan as non-smokers.
“Our study has estimated the causal effect of lifestyle choices. We found that, on average, smoking a pack a day reduces lifespan by 7 years, whilst losing one kilogram [2.2 pounds] of weight will increase your lifespan by two months,” lead author Dr Peter Joshi, added.
The researchers also highlighted how being open to new experience is good for you and that every year you spend in higher education adds 11 months to your life. While it’s good to hear, it’s important to remember that education, especially higher education, is not accessible to everyone and this correlation might be deeply linked to the inherent inequalities of our society.
The team has also identified a gene, linked to blood cholesterol level, that can reduce your lifespan by 8 months, and one linked to the immune system that can add about 6 months.
The data come from 25 separate studies from Europe, Australia, and North America.