For the first time, scientists have shown that people with superior intellectual capabilities are also more likely to live longer and experience less ill health over their lifetime.
The reason? Genes. An international team of researchers, led by the University of Edinburgh, has found that the same gene variants which make people smart, also protect them against illness.
The discovery was made after combing through the data from 112,151 participants of the UK Biobank study. After comparing each participant’s mental test data, supplied at the beginning of the study in 2006, with their genome, the researchers found that some traits linked to cognitive ability share the same genes with above-average predisposition to certain medical conditions.
“In addition to there being shared genetic influences between cognitive skills and some physical and mental health states, the study also found that cognitive skills share genetic influences with brain size, body shape and educational attainments,” said study lead author Professor Ian Deary, Director of the Centre for Cognitive Ageing and Cognitive Epidemiology (CCACE) at the University of Edinburgh.
Previously, scientists thought that socio-economic factors were the main drivers behind low academic performance and poor health. The new study, however, is a serious challenge to this view.
If Deary and his team are correct, economically disadvantaged yet intelligent people are more likely to remain healthy for longer than their wealthy, but less-bright counterparts. This holds true even in people who are at risk for certain diseases, yet remain asymptomatic.
“These results indicate that even in healthy individuals, being at high polygenic risk for coronary artery disease, type 2 diabetes or high blood pressure is associated with lower cognitive function and lower educational attainment,” wrote the team in their study.
That being said, the authors also stress that overall health is also heavily influenced by other external factors, which should not be neglected if optimal well-being is to be attained.
“This study did not address whether people with these conditions are more or less likely to have higher cognitive abilities or a degree than people without the conditions,” noted study co-author Dr Sarah Harris.
The study was published on January 26, 2016 in the journal Molecular Psychiatry.