Body mass index, obesity, and self-control: A comparison of chronotypes

The correlation between evening type, body mass index (BMI), and obesity has attracted the attention of researchers. In this study, I surveyed a sample of adults drawn from the general population in the US to examine whether or not evening types have a higher BMI than do other chronotypes and whether or not they are more likely than other chronotypes to become obese. I also proposed a personality-based explanation of the relationship between BMI, evening type, and obesity, with self-control as the mediator. As hypothesized, I found that evening types had a higher BMI and were more likely to be obese than were either morning types or intermediate types. The finding that the positive relationship between eveningness and BMI can be completely mediated by self-control is most significant.