Clinical observation suggests that stress affects weight gain. This article analyses recent clinical, epidemiological, experimental and mechanistic data. Stress can promote increased dietary intake, particularly in restrained eaters. The weight gain essentially affects the abdomen and can thus lead to metabolic syndrome and increased risk of cardiovascular disorders. Mechanisms generally observed are stimulation of the hypothalamo-pituitary-adrenal axis, cortisol synthesis in adipose tissue and stimulation of the sympathetic system. Preventive measures are described, including the possible effect of long chain omega-3 fatty acids on some points of impact.