An obesogenic bias in women's spatial memory for high calorie snack food

To help maintain a positive energy balance in ancestral human habitats, evolution appears to have designed a functional bias in spatial memory that enhances our ability to remember the location of high-calorie foodstuffs. Here, we investigated whether this functional bias has obesogenic consequences for individuals living in a modern urban environment. Spatial memory, dietary intentions, and perceived desirability, for high-calorie snacks and lower-calorie fruits and vegetables were measured using a computer-based task in 41 women (age: 18-35, body mass index: 18.5-30.0). Using multiple linear regression, we analyzed whether enhanced spatial memory for high-calorie snacks versus fruits and vegetables predicted BMI, controlling for dietary intention strength and perceived food desirability. We observed that enhanced spatial memory for high-calorie snacks (both independently, and relative to that for fruits and vegetables), significantly predicted higher BMI. The evolved function of high-calorie bias in human spatial memory, to promote positive energy balance, would therefore appear to be intact. But our data reveal that this function may contribute to higher, less healthy BMI in individuals in whom the memory bias is most marked. Our findings reveal a novel cognitive marker of vulnerability to weight gain that, once the proximal mechanisms are understood, may offer new possibilities for weight control interventions.