We hypothesized that individuals high in Neuroticism and low in Conscientiousness will have greater adiposity measured concurrently, greater fluctuations in weight over time, and larger increases in BMI across adulthood. At the facet level, we expected that participants who scored higher on impulsivity-related facets (N5: Impulsiveness, low C5: Self-Discipline, and low C6: Deliberation) will show the same pattern of associations as high Neuroticism and low Conscientiousness. In addition, because E4: Activity and C2: Order are associated with BMI concurrently (Terracciano et al., 2009), we expected active and orderly individuals to have lower adiposity, fewer weight fluctuations, and a slower rate of change. Finally, because antagonism-related traits are associated with BMI (Nabi et al., 2009) and increases in abdominal adiposity (Midei & Matthews, 2009), we expected that low Agreeableness will show a similar effect.
