Internalized weight bias predicts cortisol reactivity to social stress

Einleitung:

Weight-associated stigmatization and discrimination may induce chronic stress in individuals with obesity. As a consequence, this stressor may cause an imbalance of HPA stress axis leading to increased eating behavior, and ultimately, weight gain. However, the direct link between internalized weight bias (IWB) and stress response to acute stressors via cortisol secretion has not been investigated so far. Therefore, the aim of this study was to investigate the interaction between IWB as a chronic stressor and cortisol reactivity in an acute psychosocial stress situation induced by the Trier Socials Stress Test for groups (TSST-G).

Methoden:

Participants with BMI> 30 kg/m2 (n = 79) were included in the study. Salivary cortisol measurements were taken at three time points during the experiment: directly after arrival (T0), after TSST-G (T1) and at the end of the resting phase (T2) in order to investigate cortisol reactivity and recovery. Additionally, participants were asked to fill out questionnaires on IWB, mental health and chronic stress.

Ergebnisse:

Results reveal that while individuals with low internalized stigma reacted as predicted with an increase in cortisol secretion to acute psychosocial stress, individuals with medium or high internalized stigma did not show a typical cortisol response. However, these findings depend on the size of the testing group.

Diskussion:

In sum, chronic stress in individuals with internalized weight bias seems to blunt HPA axis reactions to acute psychosocial stress. The study contributes to the understanding of the psychological and endocrinological consequences of internalized weight bias and underlines the importance of interventions to reduce stigmatization.