Women who are motivated to eat and discount the future are more obese

OBJECTIVE: Food reinforcement and delay discounting (DD) predict Body Mass Index (BMI), but there is no research studying whether these variables interact to improve prediction of BMI. DESIGN AND METHODS: BMI, the relative reinforcing value of high (PMAX(HED)) and low (PMAX(LED)) energy dense food, and DD for $10 and $100 future rewards (DD(10), DD(100)) were measured in 199 adult females. RESULTS: PMAX(HED) (p = 0.017), DD(10) (p = 0.003) and DD(100) (p = 0.003) were independent predictors of BMI. The interaction of PMAX(LED) X DD(10) (p = 0.033) and DD(100) (p = 0.039), and PMAX(HED) X DD(10) (p = 0.041) and DD(100) (p = 0.045) increased the variance accounted for predicting BMI beyond the base model controlling for age, education, minority status, disinhibition and dietary restraint. Based on the regression model, BMI differed by about 2 BMI units for low versus high food reinforcement, by about 3 BMI units for low versus high DD, and by about 4 BMI units for those high in PMAX(HED) but low in DD versus high in PMAX(HED) and high in DD. CONCLUSIONS: Reducing DD may help prevent obesity and improve treatment of obesity in those who are high in food reinforcement.