Changes in personality and health-related behaviours during adolescence: a six-year longitudinal examination
We examined the effects of changes in personality on the health-related behaviours of adolescents over a 6-year time span. Students completed measures of Conscientiousness (C) and (Eysenckian) Psychoticism (P) in Grades 7, 8, and 9 as well as a measure of health-related behaviours in Grade 12. The protocols of 302 students were matched for each wave of data collection. Results indicated that changes in personality across the first three years of high school predicted later positive health behaviours. Thus, decreasing levels of C were related to lower frequency of eating healthy foods and exercising in Grade 12, whilst increasing levels of P predicted a reduced frequency of eating healthy foods. Interestingly, changes in personality did not predict negative health behaviours, such as junk food consumption, alcohol and drug consumption, or the number of hours watching television. These results are discussed with reference to the important effects that change and stability in personality have on health-related behavioural outcomes.