Kids Who Are Smart More Likely to Live Longer, Study Says

Kids Who Are Smart More Likely to Live Longer, Study Says
Jaedene Alyzxandra Medina, 5, poses for a photograph inside her classroom at the Child's Home Educational Center in Las Pinas, Metro Manila Philippines, on November 29. A new study suggests people who scored high on IQ tests when they were young are more likely to live longer. Erik De Castro/REUTERS

The smartest kids in the classroom may not be the most popular, but they're more likely to live longer than their not-so-smart classmates. At least that's what a new study conducted by researchers at Edinburgh University, Oxford and University College London suggests.

The study, released in the BMJ journal Wednesday, found adults who scored high on IQ tests when they were young were more likely to live longer than those who had lower IQs in their youth.

The study was based upon a survey of 75,252 men and women born in 1936, all of whom had participated in annual standardized intelligence tests in 1947. Researchers confirmed that 25,979 people had died by 2015, while 30,464 of the adults were still alive in 2017, many of whom had scored higher on the test when they were 11 years old.

After controlling for socioeconomic and behavioral factors, researchers determined people who had scored higher on IQ tests had reduced risks of dying from heart disease, stroke, respiratory diseases, stomach cancer and lung cancer by age 79.

Essentially, scientists found that a person with an IQ of 115, for instance, was 28 percent more likely to still be alive by age 76, compared with someone who scored an IQ of 100 when he or she was younger.

For every 15 extra points a participant scored on the IQ test, researchers found adults had a 28 percent reduced risk of dying from respiratory disease, were 25 percent less likely to die from coronary heart disease and had a 24 percent lower chance of dying from a stroke. Fifteen extra IQ points also reduced risks of dying from lung cancer by 25 percent, bladder cancer by 15 percent and bowel cancer by 11 percent.

Even though many of the diseases are associated with smoking, when researchers removed that specific variable, the increased chances of death in people with lower IQs weren't necessarily reduced.

The study's authors weren't able to determine why people with higher IQs were found to live longer, but one author suggested that educational opportunities, lifestyle choices, a relative lack of deprivation and genetics could be factors.

A separate study, conducted by researchers at King's College London in 2015, found a similar link between higher IQs and reduced chances of death. The study, which analyzed data from more than 200,000 men and women from 48 countries over a span of 64 years, determined the average level of intelligence globally had risen some 20 points since 1950. Researchers also discovered that as the average IQ increased around the world, life expectancy rates in a number of countries also increased.