Preliminary evidence for an impulsivity-based thrifty eating phenotype.

INTRODUCTION: Low birth weight is associated with obesity and an increased risk for metabolic/cardiovascular diseases in later life.
RESULTS: The results of the snack delay test, which encompassed four distinct trials, indicated that the gender × intrauterine growth restriction (IUGR) × trial interaction was a predictor of the ability to delay the food reward (P = 0.002). Among children with normal birth weights, girls showed a greater ability to delay food rewards than did boys (P = 0.014).In contrast, among children with IUGR, there was no such differential ability between girls and boys. Furthermore, in girls, impulsive responding predicted both increased consumption of palatable fat (P = 0.007) and higher BMIs (P = 0.020) at 48 mo of age, although there was no such association with BMI at 36 mo. DISCUSSION: In girls, the quality of fetal growth may contribute to impulsive eating, which may promote an increased intake of fats and consequently higher BMIs. As with the original thrifty phenotype, such a mechanism would be adaptive when food supplies are sparse, but would be problematic in societies with ample access to calorically rich foods.
METHODS: We examined whether the quality of intrauterine growth programs obesogenic eating behaviors, by investigating (i) the relationship between birth weight and impulsive eating in 3-year-old children (using the snack delay test), and (ii) whether impulsive eating predicts fat intake and/or BMI at 4 years of age (using a laboratory-based test meal).