Chronic stress, metabolism, and metabolic syndrome.

The prevalence of obesity has rapidly escalated and now represents a major public health concern. Although genetic associations with obesity and related metabolic disorders such as diabetes and cardiovascular disease have been identified, together they account for a small proportion of the incidence of disease. Environmental influences such as chronic stress, behavioral and metabolic disturbances, dietary deficiency, and infection have now emerged as contributors to the development of metabolic disease. Although epidemiological data suggest strong associations between chronic stress exposure and metabolic disease, the etiological mechanisms responsible remain unclear. Mechanistic studies of the influence of chronic social stress are now being conducted in both rodent and nonhuman primate models, and phenotypic results are consistent with those in humans. The advantage of these models is that potential neural mechanisms may be examined and interventions to treat or prevent disease may be developed and tested. Further, circadian disruption and metabolic conditions such as diabetes mellitus could increase susceptibility to other stressors or serve as a stressor itself. Here, we review data from leading investigators discussing the interrelationship between chronic stress and development of metabolic disorders.