Elucidating Factors that Influence Weight and Fat Mass Gain

A diverse group of male and female teenagers eating lunch in a school cafeteria. Plates full of vegetables and fruit are on the tables in front of them.

Some studies have suggested that the relative reinforcing value of food (RRV-F)—how hard a person will work for an energy-dense food when another reward is available—is greater among youth with disordered eating and high weight compared to their peers. Other work has suggested that low food-related inhibitory control—the ability to withhold a response to food-related stimuli—predicts excess weight and adiposity gain (gain in fat mass).

Most studies have considered RRV-F and food-related inhibitory control separately. The Yanovski Lab and colleagues sought to determine whether the interaction of these factors may exacerbate risk for weight and adiposity gain.

The researchers evaluated 109 healthy youth aged 8 to 17 years. Those with the poorest food-related inhibitory control had the greatest adiposity gain after three years. In contrast, RRV-F was not linked to adiposity gain or an increase in body mass index (BMI) three years later. Furthermore, RRV-F and food-related inhibitory control did not significantly interact to predict future adiposity gain. Neither food-related inhibitory control, RRV-F, nor the interaction of the two predicted changes in BMI after three years. Changes in BMI do not directly measure changes in adiposity because BMI is the sum of bone mass, lean mass (e.g., muscle and internal organs), and fat mass.

The results suggest that food-related inhibitory control may be a more important risk factor than RRV-F for adiposity gain among healthy youth, suggesting that programs to improve inhibitory control might help children avoid undue weight gain. Additional data are needed to replicate these findings and to determine how other youth eating behaviors and traits may interact to promote excess weight gain over time.

Learn more about the Developmental Endocrinology, Metabolism, Genetics, and Endocrine Oncology group: https://www.nichd.nih.gov/about/org/dir/affinity-groups/DEMG-EO