Intelligence is directly genetically linked to longevity according to a new study published in the International Journal of Epidemiology.
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Previous studies have shown that clever people live longer, but the underlying cause has remained unidentified. Now, researchers at the London School of Economics have shown that genes account for 95 per cent of the connection.
By looking at twins, both identical and non-identical, where at least one of the pair had died, the researchers found that in 19 out of 20 cases the more intelligent twin outlived the less intelligent one because of slight differences in their genes.
The findings were the same for twin samples from Sweden, Denmark and the US. The underlying cause, according to the report, was that the more intelligent one of the pair tended to suffer fewer genetic mutations.
Rosalind Arden, a research associate at the LSE, told The Times that "the association between top jobs and longer lifespans is more a result of genes than having a big desk.”
We know that children who score higher in IQ-type tests are prone to living longer. Also, people at the top of an employment hierarchy, such as senior civil servants, tend to be long-lived. But, in both cases, we have not understood why.