“Stress eating” is a term we often hear and use in our day-to-day lives. In stressful situations, we may cope with our emotions by indulging in comfort foods. For example, when stressed about an upcoming exam, students may overeat or eat unhealthy and high-calorie foods while studying to help deal with this stress. It is important to consider the role of stress on emotional eating, and the brain regions that play a role in regulating energy balances, food intake, and stress response.
Over 23% of children and adolescents in developed countries are overweight or obese. Adolescents with excess weight may be particularly sensitive to stress and are often victims of bullying and social exclusion from their peers. This stress can ultimately make adolescents who are already struggling with excess weight more vulnerable and responsive to their emotions and can in fact encourage obesity. Further, stress may increase food consumption and the intake of high-calorie foods. Adolescents with excess weight can feel isolated from their peers and seek food (specifically unhealthy food) as a form of comfort. Emotional eating behaviors are used as a way for overweight and obese adolescents to cope with stressful situations.
A theory proposing the “emotional nervous system,” considers regions of the brain involved in eating behavior and the control of eating in emotional and stressful situations. This theory suggests that stressful situations increase the functioning of certain brain regions involved in emotion, “food-memories,” motivation and reward. This increase in functioning can result in the overriding of mindful eating. The emotional nervous system includes the following brain regions: the hypothalamus, the midbrain, the striatum, the amygdala, and the insula.
Previous research highlights the hypothalamus as a key brain area for studying stress and food intake. The lateral hypothalamus is involved in increasing eating and the medial hypothalamus is involved in inhibiting eating behaviors. Studies have found that overweight adults versus normal weight adults show differences in functional connectivity of the lateral and medial hypothalamus. The present study by Martin-Pérez, Contreras-Rodríguez, Vilar-López, and Verdejo-Garcia (2019) explored the functional connectivity of the lateral and medial hypothalamus in adolescents with excess weight versus normal weight, to see if the same brain differences were found. Martin-Pérez et al. (2019) looked at differences in the hypothalamic networks of the brain in association with stress levels and emotional eating patterns in adolescents. They assessed brain differences in the medial and lateral hypothalamus using an MRI scanner, stress using the Trier Stress Social Task and measures of cortisol levels and assessed emotional eating behaviors using the Dutch Eating Behavior Questionnaire.
Martin-Pérez et al. (2019) found that adolescents with excess weight did indeed have higher functional connectivity in these brain regions (lateral and medial hypothalamus) compared to adolescents of normal weight. This finding shows that brain differences in the hypothalamus are present at an early age in adolescents with excess weight. Positive connections were found between the lateral hypothalamus, stress response and emotional eating in adolescents with excess weight. This suggests that overweight and obese adolescents who are more sensitive to stress have greater motivation to eat and have higher emotional-eating behaviors. Further, this study supports the “emotional nervous system” theory; Martin-Pérez et al. (2019) found that an increased connectivity in the lateral hypothalamus-midbrain network was associated with higher responsiveness to stressful situations and increased eating behaviors.
Martin-Pérez, C., Contreras-Rodríguez, O., Vilar-López, R., & Verdejo-García, A. (2019). Hypothalamic networks in adolescents with excess weight: Stress-related connectivity and associations with emotional eating. Journal of the American Academy of Child & Adolescent Psychiatry, 58 (2), 211-220.
