I.3.6 Personality Characteristics that increase happiness and longevity
It turns out that there is a direct link between personality characteristics, and health and longevity. Having certain personality characteristics is good for your health, while others will reduce your life expectancy and wellbeing. The most popular personality classification used for psychological research is the “Big Five”, which measures the five personality characteristics Openness, Conscientiousness, Extroversion, Agreeability, and Neuroticism, also known under the acronym OCEAN. Openness to experience looks at whether you are stuck in your old ways, or open to new ideas and innovations. Conscientiousness measures your orderliness and tidiness, and how predictable your behavior is, if you do what you say. Extroversion tracks your social behavior, are you an introvert who is happiest alone at home reading a book, or do you prefer to be constantly surrounded by other people and be the heart and soul of a party. Agreeability looks at how easy you are to get along with, are you willing to overlook small offenses and slights, or are you blowing up at the smallest offense, imagined or real. Neuroticism measures how much you worry, how moody, easily depressed, and anxious you are. In a large-scale statistical analysis with 6904 participants in the US, it was found that all five OCEAN characteristics influence your propensity to have certain diseases. Your likelihood of having high blood pressure, diabetes, cancer, lung disease, a heart condition, a stroke, or arthritis are all related to your personality. High conscientiousness, extroversion, openness, agreeability, and low neuroticism are all associated with better health. In particular high conscientiousness and low neuroticism reduce the chances to develop a stroke and lung disease, as does high openness. The causal link between extroversion and agreeability and good health is less prominent. Doing what you say, showing consistent behavior, cleaning up, and being orderly have a direct positive influence on your wellbeing, as does being open to new ideas, being willing to try out new things, and worrying less and adopting an optimistic attitude.
Men who are more conscientious and more open, and women who are less neurotic, and more agreeable live the longest. In a longitudinal study, researchers followed 600 couples living in 1935 in the state of Connecticut over the period from 1935 to 2013. Different from many other studies comparing personality with well-being and longevity, the people in the study cohort did not self-answer the FFI survey questions, rather the personalities were assessed by three to five friends of each participant. The researchers found that men with one positive standard deviation increase in conscientiousness had a 29% decrease in mortality risk, a similar increase in openness was associated with a 15% decrease in mortality risk. Similarly, emotionally more stable and more agreeable women had a 15% decrease in mortality risk. The interesting point is that the personality ratings done by their peers were a better predictor of mortality risk than the self-ratings. For men the effects for the self-ratings where directionally similar to the peer-rated personality characteristics, but smaller with a 13% mortality risk decrease for both higher conscientiousness and higher openness. For women the self-rated personality characteristics were not correlated with any effect on longevity at all. This suggests that frequently we are not honest to ourselves, in particular when assessing ourselves in personality surveys, it also seems that women are less honest to themselves than men, where at least the effect still remained, although at reduced size. In a further analysis, the researchers found that friends of a male were particularly good in identifying people with low conscientiousness, and thus with a higher risk of earlier death.
The good news is that personalities change over time. While psychologists in the better part of the twentieth century assumed that once somebody was grown up, their personality was cast in stone, this is not the case. Using the same cohort of 600 couples, when retesting the 600 individuals after one year, the correlation between their original personality values and the answers after one year was about 70%, when repeating the test after twenty years, the correlation dropped to 50%, indicating large changes in the self-answered personality scores. We are the product of our past experiences, which greatly influence how we act today. For instance, in the same project, the attitude towards marriage of the 600 participants correlated less than 7% with the original answers given twenty years before. Conscientiousness correlated at about 38% with the ratings given twenty years before. This means that people experienced a huge change in this personality characteristic essential for wellbeing and a long life. There were also changes of 52% in the moral values of the participants over the twenty years.
Changing your personality is an actionable way to increase happiness and live to an old age in better health. Listen to your friends and try to be more conscientious, more open for new ideas, and to worry less. Measure it and be told when you deviate from the good ways. The conclusion therefore is that it is better to ask your friends to assess your personality characteristics, than answering the survey questions yourself. Or even better, use an AI system that uses the aggregated wisdom of the swarm to measure your personality based on your honest signals of collaboration, as shown later in part II.