Efficacy of myo-inositol and zinc on insulin resistance in a paediatric population with obesity.

Aim: To assess the efficacy of the combined administration of myo-inositol and zinc, a mineral involved in the insulin pathway, in paediatric obesity with insulin resistance on HOMA-IR, glucose-insulin metabolism, and lipid profile.

Materials and methods: Double-blind, randomized, placebo-controlled study conducted in North Italy. Fifty-six patients (10-18 years, Tanner stage ≥3) with obesity and insulin resistance were randomized to myo-inositol (2000 mg), zinc gluconate (5 mg), and galactooligosaccharides (GOS) from plant-based origin (1000 mg) (TRT) or placebo (PLC) containing only GOS from plant-based origin (1000 mg). All patients received an isocaloric diet following the Mediterranean diet style. Data were collected at baseline (V0) and after 3 months (V1). The primary outcome was the insulin resistance index (HOMA-IR).

Results: Fifty out of 56 recruited subjects completed the study. TRT improved HDL cholesterol level compared to PLC (p = 0.05) but not insulin resistance. A stratified post hoc analysis was performed by sex, BMI, and subgroups of adherence to the Mediterranean diet. Subjects were divided for obesity grade, fasting insulin (p = 0.0137) and HOMA-IR (p = 0.0273) were lower in TRT than in PLC patients, with a greater effect on severe obesity. No adverse events were detected.

Conclusion: Three months of supplementation with myo-inositol and zinc were beneficial on lipid profile and in managing obesity complications at least in subjects with severe phenotype. Thus, myo-inositol and zinc could be used as non-pharmacological agents. This work suggests a long-term study with a larger sample size to enrich the findings.