The role of interoception in age-related obesity: A structural equation modelling study

The obesity pandemic and its adverse effect on health and quality of life are well established. In younger populations, interoception and aberrant eating behaviour contribute to overconsumption and being overweight. Although the incidence of obesity is higher in older individuals, they remain under-researched in the obesity literature. Therefore, the present study considered the role of general (interoceptive sensibility) and appetite-specific (hunger drive and satiety responsiveness) interoception and obesogenic eating behaviour (food responsivity, emotional eating, enjoyment of eating) in the association between age and BMI. A total of 1006 female adults (aged 18 to 80) completed the Adult Eating Behaviour Questionnaire and the Interoceptive Attention and Accuracy scales. Structural Equation Modelling (SEM) in AMOS was used to explore the data for multiple serial mediation effects. Despite being more overweight, older adults reported lower interoceptive attention, hunger drive, emotional overeating, food responsivity, and enjoyment of food. In contrast, compared to younger adults, older adults reported a higher interoceptive accuracy, and a similar responsivity to satiety. Importantly, two indirect pathways positively mediated the link between age and BMI: (1) age ➤(-)➤ interoceptive attention ➤(+)➤ satiety responsivity ➤(-)➤ emotional eating ➤(+)➤ BMI and (2) age ➤(-)➤ interoceptive attention ➤(+)➤ satiety responsivity ➤(-)➤ food responsivity ➤(+)➤ BMI. However, a stronger antagonistic indirect pathway was also present: age ➤(-)➤ interoceptive attention ➤(+)➤ hunger drive ➤(+)➤ emotional eating ➤(+)➤ BMI. The present findings suggested that overall reduced interoceptive attention in older adults may protect against weight gain by lowering hunger and the propensity towards obesogenic eating behaviours. These findings have implications for the design of appetite interventions in older populations.