[Epidemiology of obesity]

Overweight and obesity are conditions characterized by weight levels higher than the normal limits for age, sex, and height. Because people stratified for sex and age vary in stature and this influences weight, criteria for being overweight must take height into account: this is defined and set out in WHO guidelines on the basis of Body Mass Index (BMI): weight (kg)/height2 (m2). Obese and overweight individuals are at a greater risk of developing chronic metabolic conditions and general ill health, than those whose weights are within the recommended guidelines. Besides these chronic related conditions for which obesity is a major risk factor incur enormous expenditure. The health hazards of obesity are compounded by the influence of central fat distribution. The disease associations of central fat are present even in people who are not overweight. Waist circumference is a simple measure that gives a very reasonable estimate of the amount of central fat. Data collected in the USA and Europe show a common trend: the increase of obesity and overweight among the adult and children population. Obesity appears to be the result of several factors that interact among them such as: genetic, environment, and behaviour. Current strategies, such as reducing food intake, seem to lead to poor long term outcomes. Management has tended to neglect the unavoidable need to consider obese subjects as chronically ill patients, requiring continuous assistance for active steps to maintain weight loss. Treatments should be multidisciplinary aiming at the achievement of radical changes in the individual's lifestyle. The planning and management of preventive programs for young people such as pubertal children have been disregarded up to now. They require not only attention, but also organization, clear goals and standardized methods. Moreover, a correct education is a key-element of these issues. Our unit has designed for this purpose an observational study aimed to reach a better comprehension of the proportion of ''weight problems'' and eating behavioural patterns in a population of adolescents.