Visceral obesity is a strong predictor of type 2 (non-insulin-dependent) diabetes and is associated with insulin resistance. In addition, research has indicated that the accumulation of visceral fat is regulated by endocrine mechanisms. Data suggest that progressive malfunction of the hypothalamic-pituitary-adrenal (HPA) axis, with elevation of levels of cortisol and reductions in levels of sex steroids and growth hormone, is associated with visceral accumulation of fat that contributes to circulating levels of free fatty acids, and that these factors are implicated in the development of insulin resistance. Furthermore, failure of central feedback control of the HPA axis by glucocorticoid receptors (GR) appears to be correlated with polymorphisms near the first exons of the GR gene. The HPA axis disturbances are similar to those seen after prolonged exposure to environmental stress. Psychosocial and socioeconomic factors, alcohol, depressive traits and anxiety are linked to HPA axis abnormalities.