Smart People Live Longer Because of Intelligence & Longevity's Genetic Link

Researchers have found a genetic link between being smart and having a long life span. According to the official website of The London School of Economics and Political Science, the study was published in the International Journal of Epidemiology.

In the study, researchers discovered that a person's genetic make-up is 95 percent responsible for the link between how smart a person would be and how long a person had lived, reports The Scotsman.

Rosalind Arden, a research associate from LSE who was involved in the study, explained that the study focused on why children who exhibited higher intelligence and scored higher on IQ-type tests seemed to live longer.

She said she and other researchers of the study also wondered why high-ranking employees, similar to those who are senior civil servants, also lived for longer periods of time.

It would seem that studies in the past have always revealed that there is a link between intelligence and longevity, but the link was not clearly defined prior to Arden and her colleagues study.

"Our research shows that the link between intelligence and longer life is mostly genetic," said Arden.

For the research, Arden and her colleagues analyzed three different studies involving identical and fraternal twins, states Science Daily. The studies were retrieved from Sweden, the United States and Denmark. Included in the data of the studies were the individuals' intelligence and age of death, since at least one twin died in each of the cases observed.

Twins are the perfect subjects for genetic studies since they have similar DNA and shared environmental factors, like housing or parenting history. For this study, identical twins, whose DNA is completely the same, were compared to fraternal twins, since half of their DNA is different from their twins.

After analyzing the studies, Arden and her colleagues found that the brighter twin tended to outlive his/her sibling, who was defined as "less bright," reports Science World Report.

The findings were even more significant when applied to fraternal twins, meaning that even with only half their genes being different, it played a big role in terms of intelligence and lifespan.

Arden tried to make sense of the findings by hypothesizing that the genes which make a person smarter could also be responsible for making the person's body healthier.

She went on to say: "...Or intelligence and lifespan may both be sensitive to overall mutations, with people with fewer genetic mutations being more intelligent and living longer...."

Arden expressed the need for further study in order to fully understand the genetic link found between intelligence and longevity in their study.

However, Arden stressed that parents should not assume they can gauge their child's lifespan based on their test scores, since the connection between the two is still somewhat small.