In this article, information on the definition of obesity in childhood and adolescence, its differential diagnosis and its adverse health effects is provided. This information can be considered as a basis for the evaluation of an obese patient. Review of the international and European literature shows that the co-morbidities of childhood obesity cover a large medical area ranging from secondary hormonal disturbances to orthopaedic problems. Most of them have so far been underestimated. However, the most severe problem of an obese child is his or her psychosocial discrimination. Longitudinal data demonstrate a positive relationship between childhood obesity and increased morbidity and mortality in adulthood.
Conclusion: Data from the literature are in some respect sparce since they do not allow to calculate the exact prevalence of adverse effects nor to assess the outcome of an obese child when it is successfully reducing the relative amount of body fat.