ESPE Abstracts

Background: Dietary carbohydrate restriction in the treatment of obese adolescents could cause a substantial shift in the substrates used as an energy source, inducing changes on body composition and metabolism, but experience in this age range is limited.

Objective: We assessed the influence of 6 months of dietary carbohydrate restriction on body composition and lipid and carbohydrate metabolism in obese adolescents.

Method: Thirty-six (15.8±1.5 years; 22 girls/14 boys) obese (+4.72±2.80 BMI-SDS) Caucasian adolescents were recruited and analyzed monthly. Two nutritional interventions with similar caloric content (1500 kcal/day) were compared: limited carbohydrates (CH-L, n=19, 10% carbohydrates for 4 months and 30% later) vs. unrestricted carbohydrate diet (CH-N, n=17, 52% carbohydrates). Patients were studied at recruitment (R) and after 3 (3M) and 6 months (6M). BMI, body composition (BIA, Tanita® BC-420MA), glycemia, insulinemia, HOMA, lipid profile, uric acid and serum 25[OH]vitamin-D levels were recorded.

Results: Both groups reduced their BMI-SDS at 6M (P<0.001), with this being greater in the CH-L group (−1.70±0.98 vs −0.80±1.09 in the CH-N; P<0.05) due to a larger reduction in the first 3 months (−1.41±0.71 vs. −0.62±0.78 in the CH-N; P<0.001) as the BMI-SDS evolution between 3 and 6 months was similar. This loss in BMI was due to a decrease in fat mass. A transient rise in uricemia was observed in the CH-L group at 3M (P<0.01), which normalized at 6M. HOMA improved exclusively in the CH-L group at 6M (−1.75±1.48 vs. +0.15±1.25 in CH-N; P<0.001). No significant differences within or between groups were observed in the evolution of the lipid profile, but both groups showed an increase in vitamin-D levels at 6M after weight loss (P<0.001).

Conclusion: Diet carbohydrate restriction results in a more intense weight reduction and insulin resistance improvement in obese adolescentes after 6 months of treatment.