Trajectories of physical growth and personality dimensions of the Five-Factor Model.

Although physical growth in early life is associated with the risk of somatic illnesses and psychological disorders in adulthood, few studies have focused upon the associations between growth and dimensional personality traits. We examined the associations between pre- and postnatal growth in height, weight, and body mass index (BMI) and Five-Factor Model dimensions in adulthood. From the Helsinki Birth Cohort Study, 1,682 participants completed the NEO Personality Inventory (NEO-PI) at an average age of 63 years. Growth estimates were derived based on medical records. Adjusting for gestational length and sociodemographic variables, birth weight showed a quadratic association with neuroticism; participants with low birth weight scored the highest on neuroticism. Larger ponderal index at birth predicted higher agreeableness, while average ponderal index predicted higher conscientiousness. BMI and weight growth trajectories from birth to adulthood were associated with agreeableness and conscientiousness. More specifically, less BMI and weight gain between 7 and 11 years and/or between 11 years and adulthood were associated with higher conscientiousness and higher agreeableness. Height and weight growth trajectories from birth to adulthood were associated with extraversion: faster height and weight growth between birth and 6 months, slower height growth between 7 and 11 years, and faster weight gain between 11 years and adulthood were associated with higher extraversion. Openness to experience was not associated with growth. This longitudinal study supports an association between pre- and postnatal physical growth and 4 of the Five-Factor Model personality dimensions in adulthood.