People with better health are more likely to be intelligent, a study led by the University of Edinburgh claims. The researchers show that it all comes down to the genes that protect people from diseases, which are the same genes that make people smart.
The research team assessed data from 100,000 people, ages 40 to 73 years, in the UK Biobank that contains genetic data, health and cognitive variables of participants. They observed that some traits associated to disease and cognitive skills are influenced by the same genes.
The participants were given mental tests that analysed their reaction time, memory and their verbal-numerical reasoning. Those who performed the best on these tests were less likely to have the genes associated with Alzheimer’s disease, diabetes, high blood pressure or generally poor health. Plus, these participants were also taller and possessed bigger brains.
According to researcher Saskia Hagenaars of Edinburgh University, this study reinforces the idea that overall health is linked with higher levels of intelligence. Apparently, being taller is also related to obtaining a college degree and people who are prone to cardiovascular diseases tend to have lower reasoning ability.
Lead researcher Ian Deary, director of the Center for Cognitive Ageing and Cognitive Epidemiology (CCACE) at the University of Edinburgh, adds that their study shows that apart from physical and mental health, the brain size, body shape and educational attainments also share genetic influences with cognitive skills.
Scientists thought that socio-economic factors are linked with low education and poor health, but this study proves that even poor intelligent people are more likely to be healthier. However, intelligence seems to increase the chances of developing schizophrenia, bipolar disorder and autism.
The researchers maintain that many environmental factors can influence health over time. Nevertheless, this highlights the importance of studying biological pathways that influence both cognitive function and health related traits which can help experts further understand the links between these things.