Cortico-limbic responsiveness to high-calorie food images predicts weight status among women

Abstract

Excessive weight gain and obesity are currently among the world's major threats to health. Women show significantly higher rates of obesity and eating disorders relative to men, but the factors contributing to these gender differences remain uncertain. We examined the correlations between regional brain responses to images of high-calorie versus low-calorie foods and self-reported motivational status, including ratings of general appetite, overeating propensity, state hunger and desire for specific foods. Thirty-eight healthy right-handed adults (22 male; 16 female) ages 18-45 participated. There were no differences between males and females with regard to age or body mass index (BMI). Overall, motivational status correlated significantly with activation within the amygdala, insula and orbitofrontal cortex. Regional activation was then used to predict BMI, an indicator of long-term food consumption and energy expenditure. The combined model was significant, accounting for 76% of the variance in BMI for women, whereas the same regions were not predictive of weight status among men. Findings suggest that long-term weight status is related to visual responsiveness to calorie-dense food imagery among women.