Stress-Related Weight Gain: Mechanisms Involving Feeding Behavior, Metabolism, Gut Microbiota and Inflammation

The body stress response is a highly adaptive phenomenon activated by different types of physical and emotional stressors. Chronic and/or excessive stress is, on the other hand, often maladaptive. In this short review we deal with the influence of the stress response on weight gain and fat accumulation. Chronic stress appears to promote a shift from homeostatic regulation of food intake to hedonic overeating. Hyperactivation of the stress response triggers metabolic changes that might slow down energy expenditure while promoting visceral fat accumulation. Chronically elevated glucocorticoid levels also enhance the inflammatory response and cytokines secreted by visceral fat can in turn increase metabolic abnormalities towards obesity. Changes in the gut microbiota, which is highly sensitive to the stress hormones as well as to the type of food ingested, can also be involved in stress-related weight gain. Given the vicious circles that interlock stress, food, metabolism and inflammation, strategies for stress control and management should be taken into account to prevent weight gain particularly in Western-lifestyle countries.