Back in 1932, almost every single 11-year-old in Scotland was surveyed as a part of the Scottish Mental Survey. All of the children were given the same IQ test and the data was updated throughout their lives until they passed away. Researchers have gone through all of that data from the last 84 years and found an interesting correlation: smarter people live longer lives. Even when factors like economic status and other lifestyle-related variables were taken out of the equation, the data held up.
According to the report done by Larence Whalley from the University of Aberdeen and Ian Deary from the University of Edinburgh, which was published in the British Medical Journal, a child with an IQ of 115 was 21% more likely to live past the age of 75. In their findings, they said, “Subjects who died before 1 January 1997 had a significantly lower mean IQ at age 11 years than subjects who were alive or untraced. Our data shows that high mental ability in late childhood reduces the chances of death up to age 76 years.” There are two theories for why this data makes sense:
Smarter People do Less Dumb Stuff
This hypothesis makes the most sense to me. Smarter people are more likely to do things like buckle-up in their car or eat a healthier diet. Smarter people are also less likely to smoke or use drugs because of their knowledge of the negative side effects. More importantly, smart people do less dumb stuff. Just think about how many people die every year from just stupid things? That’s why the Darwin Awards exist. The concept of “survival of the fittest” works on humans too, and smarter people are fitter for survival.
Another theory is that smarter people literally have better nervous systems. A study that was published in 2005 discovered that people who had better reaction times lived longer lives. The Theory is that better reaction times are a sign that the subject’s nervous system was more efficient, and therefore, make people live longer.
Read: Researchers Find That People Who Use Curse Words Could Be Smarter And More Articulate
In addition, to that theory was the idea that IQ and longevity are both functions of genetics. David. Z Hambrick, a writer for Scientific American, cited a study of twins that showed that longevity and intelligence were products of good genes. According to Hambrick, “Twin studies disentangle the effects of environmental and genetic factors on an outcome such as intelligence or lifespan by comparing identical twins, who share 100 percent of their genes, and fraternal twins, who on average share only 50 percent of their genes.
[The researchers] performed statistical analyses to estimate the contribution of genetic factors to the IQ-lifespan relationship. The results were clear and consistent: genes accounted for most of the relationship.”