Researchers at the University of Edinburgh have found strong genetic evidence linking children’s intelligence to how long their parents live. The study, led by Dr W. David Hill and published in Genomic Psychiatry, is the first to show, at the molecular level, that genes influencing children’s cognitive ability also relate to lifespan. This discovery provides a scientific explanation for a well-known observation in public health: children who perform better on intelligence tests tend to live longer lives.
For decades, researchers have seen that higher childhood intelligence scores are associated with a lower risk of early death. Extensive studies from the UK, Denmark, Israel, and Sweden have shown that children with higher test scores are far more likely to live longer, regardless of their family’s income, later schooling, or social background. However, the biological reason behind this link has remained unclear. Previous findings could not rule out the possibility that poor health in adulthood might lower cognitive scores and reduce lifespan, creating a false association.
To avoid this problem, Hill’s team focused specifically on cognitive data gathered in childhood, before health problems could affect test results. They analysed genetic information from more than 12,000 people who had taken intelligence tests in youth and nearly 390,000 people whose parents’ ages at death were recorded. Using advanced statistical tools, the team measured the extent to which the genetic influences on intelligence and longevity were similar.
The results were striking. The study found a genetic correlation of 0.35 between childhood intelligence and parental lifespan, meaning the two traits share a substantial portion of their genetic basis. The research also confirmed that genes strongly influence both intelligence and longevity. Notably, the analysis showed little evidence of bias from population differences, reinforcing the reliability of the findings.
The reason these shared genes affect both brain function and longevity remains uncertain. One explanation supports the “system integrity” idea: some people may inherit biological systems—such as more efficient cells or stronger immune responses—that naturally support both better thinking skills and longer, healthier lives. Another possibility is that intelligence indirectly supports longevity. Children with higher cognitive ability may grow up to make healthier choices, achieve better education and income, and avoid harmful behaviours, all of which support longer life.
This research opens new opportunities for studying which specific genes support both cognition and health. Understanding these biological pathways could help scientists develop strategies to support healthy ageing or identify those at higher medical risk earlier in life. However, the authors stress that genes are only part of the picture. Lifestyle, access to education, nutrition, and social conditions still profoundly influence lifespan.
The findings also suggest important implications for public health. Supporting and improving children’s cognitive development may offer benefits that extend far beyond academic success. Investing in education and childhood wellbeing may contribute not only to smarter societies, but also to healthier, longer-living populations. While genes cannot be changed, improving childhood environments may work alongside biology to support a longer, healthier life for future generations.
More information: W. David Hill et al, Shared genetic etiology between childhood cognitive function and longevity, Genomic Psychiatry. DOI: 10.61373/gp025l.0098
Journal information: Genomic Psychiatry Provided by Genomic Press
