[Semiology of obesity]

Obesity is a syndrome defined simply as an excess of body fat. It is becoming increasingly clear that the condition is multifactorial and has a wide range of causes. Detailed analysis of the clinical presentation is the basis of the diagnosis of the pathophysiological mechanism at work in each individual case and a prerequisite for the determination of the therapeutic strategy. Although there is no ideal system of classification, an attentive medical, dietary and psychological examination often provides relevant information to decide what is useful, possible or even harmful for the patient.