[Metabolic response to food and diet in paediatric obesity].

Obesity has reached today epidemic proportions in industrialized countries with negative effects on children and adult's health, and excessive costs for society. Although genetics and ambient are surely implicated in determining the positive energy balance in the organism, to our known few has been written on the role of macronutrient (proteins, fats and carbohydrates) in diet, particularly in children, in the onset and develop of obesity. Children's eating patterns and habitudes have been hanged in the last years, so that there is an higher intake of PUFA (poliinsatured fat acids) and lower of MFA (monoinsatured fat acids), and an elevated density of carbohydrate in the diet. Considering the effects of macronutrients on body energetic metabolism , it is clear that in obese children there is an higher oxidation of exogenous carbohydrates and a lower oxidation of endogenous ones; this effect conducts in short term to an increment of tissue fat and to a consequent increment of body weight. High fat intake and fat oxidation influence the accumulation of fat mass rather over a long term in children. Fat oxidation is favourite also by the assumption of high glycemic index foods, that conducts to insulin-resistance. A low fat diet, rich in low glycemic index carbohydrates that can reduce hungry and avoid insulin resistance, acts together to a regular and aerobic constant physical activity, which helps fat mobilization from adipose tissue and from muscles, and can reduce insulin-resistance, so favouring weight loss.