If you have this personality trait, you may live longer

Just like family, no one gets to pick their personality. If that were the case, the world would probably be filled with smiling, outgoing optimists. That version of reality certainly sounds pleasant, but it also sounds pretty boring doesn’t it? Different personalities and perspectives are a big part of what makes every day a new experience.

That being said, a new study just released by the University of Limerick is making a compelling case for all of us to be more conscientious. Prior research had already found evidence suggesting people who score high for the personality trait conscientiousness tend to live longer than those with low levels of conscientiousness. 

Now, this new study has begun to explain why personality impacts longevity. Researchers connected the immune system to this equation; the personality trait conscientiousness appears to have a direct influence over one’s immune system.

“Personality is known to be associated with long-term risk of death, it is a well replicated finding observed across numerous research studies internationally,” explains Principal Study Investigator Dr. Páraic Ó Súilleabháin, from the Department of Psychology and Health Research Institute at University of Limerick, Ireland. “The critical question is ‘how’. We wanted to find out if a biological pathway such as our immune system may explain why this happens.”

Conscientiousness is defined as “the quality of wishing to do one’s work or duty well and thoroughly,” or “a tendency to be responsible, organized, and capable of self-control.” So, based on these findings, it isn’t a stretch to say that when we act more responsibly and diligently in life, our immune systems follow the same pattern.

“Our personality is critically important throughout our lives, from early stages in our development, to the accumulation of the impact of how we think, feel, and behave across our lives, and in the years preceding our death. It is also becoming increasingly apparent how important personality actually is for our long-term health and resulting longevity. For instance, it has been shown that people scoring lower on the personality trait of conscientiousness can be at a 40% increased risk of future death compared to their higher scoring counterparts,” Dr. Ó Súilleabháin adds.

To investigate if the immune system is involved at all in this relationship between conscientiousness and mortality, the study authors focused on two integral immune system biomarkers. Those two biomarkers, interleukin-6 and the c-reactive protein, are both considered major players when it comes to age-related morbidity. This was accomplished by analyzing data on 957 adults originally collected over 14 years for the Midlife in the United States Longitudinal Study.

Sure enough, the researchers’ work revealed that people who score high in conscientiousness tests generally show lower levels of interleukin-6.

“We found that part of the reason why people who score higher on the personality trait of conscientiousness live longer is as a result of their immune system, specifically due to lower levels of a biological marker called interleukin-6. There are likely further biological mechanisms that are yet to be discovered which will give a clearer picture of all the different ways that our personalities are so critical to our long-term health,” Dr. Ó Súilleabháin says.

“These findings are very important and identify for the first time that an underlying biological marker directly links personality to long-term mortality risk. With replication, these findings provide an opportunity for future interventions to increase our longevity and health across the lifespan,” he concludes.

This study is only the first step to fully understanding the full spectrum of connections between personality, longevity, and the immune system. Still, it should give all of us some new motivation to be more conscientious. It’s true that some people are naturally more conscientious, but anyone can become more organized and responsible with the right amount of sustained effort.

The full study can be found here, published in Brain, Behavior, and Immunity.