Background: Previous studies showed that cognitive ability is related to health and mortality. The cause of this relationship remains largely unknown. One plausible explanation is that cognitive ability is related to behaviours that affect health. This study investigates whether cognitive ability is related to healthy dietary habits, physical activity and appropriate bodyweight in adolescents and examines whether self-control mediates the relationship between cognitive ability and health behaviour.
Methods: In total 201 high-school students aged between 15 and 20 participated in the study. They completed three cognitive tests, measuring cognitive ability, reaction time and memory span, and completed a questionnaire on self-control, dietary habits, physical activity and bodyweight.
Results: Results show that adolescents scoring high on the cognitive ability test have healthier dietary habits and engage more often in physical activity. Adolescents with high self-control have a healthier eating pattern, are more often physically active and have lower BMI's. Both reaction time and memory span were not related to dietary habits and physical activity. Self-control was not related to cognitive ability and could not, therefore, mediate the relationship between cognitive ability and health in this study.
Conclusion: In conclusion, the link between cognitive ability and health behaviour could explain - in part - the relationship between cognitive ability and health. Self-control cannot explain this link.