[Metabolic aspects of obesity]

Classification of obesity in accordance with a new anatomical and functional criterion means that a hyperplastic and a hypertrophic form can be distinguished. The distinction is of both academic and practical significance, since different metabolic changes are observed in the two forms. Hyperplastic obesity appears early in life and is particularly intractable. It is not usually accompanied by dysmetabolic signs, however. Hypertrophic obesity, on the other hand, is accompanied by endocrine and metabolic alterations, marked by insulin resistance, sugar intolerance, hyperinsulinaemia, hypertriglyceridaemia, and hyperuricaemia. Recent data are cited for the proposition that these changes constitute a closed pathogenetic concatenation creating a vicious circle. Fatty acids play a particularly important part in this context, since they are synthetized, released, presented and oxidated to a pathological degree.