Abstract
BACKGROUND: There is considerable anecdotal and some scientific evidence that stress triggers eating behavior, but underlying physiological mechanisms remain uncertain. The hypothalamic-pituitary-adrenal (HPA) axis is a key mediator of physiological stress responses and may play a role in the link between stress and food intake. Cortisol responses to laboratory stressors predict consumption but it is unclear whether such responses mark a vulnerability to stress-related eating or whether cortisol directly stimulates eating in humans. METHODS: We infused healthy adults with corticotropin-releasing hormone (CRH) at a dose that is subjectively undetectable but elicits a robust endogenous cortisol response, and measured subsequent intake of snack foods, allowing analysis of HPA reactivity effects on food intake without the complex psychological effects of a stress paradigm. RESULTS: CRH elevated cortisol levels relative to placebo but did not impact subjective anxious distress. Subjects ate more following CRH than following placebo and peak cortisol response to CRH was strongly related to both caloric intake and total consumption. CONCLUSIONS: These data show that HPA axis reactivity to pharmacological stimulation predicts subsequent food intake and suggest that cortisol itself may directly stimulate food consumption in humans. Understanding the physiological mechanisms that underlie stress-related eating may prove useful in efforts to attack the public health crises created by obesity.