RESUMO
The aim of this study is to compare the weight loss of obese adolescents on two different low-calorie diets: fixed diet plan and calorie-counting diet. This is a randomized clinical study with 66 obese adolescents (body mass index Z score (ZBMI)>+3, 13.7±0.7 years, 60.6% male) with anthropometric, food intake, physical activity, laboratory, body composition and stage of pubertal development data evaluated. There was a reduction in the ZBMI in both groups (P<0.0001), without significant difference between them (P=0.87). There was a significant reduction in insulin, and homeostasis model assessment insulin resistance (HOMA-IR), with no difference between groups. A reduction in total energy intake of the groups was found, with an increase in the proportion of protein and reduction in carbohydrates. In this cohort of severely obese adolescents, fixed diet plan and calorie-counting diet led to a similar reduction of ZBMI, metabolic markers and total energy intake.