RESUMO
Objective: To determine whether overweight children and adolescents have lower serum concentration and lower dietary intake of magnesium compared to those with normal weight; and to study the correlation of serum magnesium levels with components of metabolic syndrome in children and adolescents. Design: Cross-sectional, comparative study. Setting: General/Pediatric Endocrinolgy OPD tertiary care medical centre. Study done from July 2007 to March 2009 Participants: 55 overweight and 53 normal weight children and adolescents aged 4 years to 14 years. Methods: We compared fasting levels of serum magnesium, insulin, glucose, total and HDL-cholesterol, triglycerides and dietary magnesium intake. Results: The serum magnesium levels were significantly lower in overweight (2.12 ± 0.33 mg/dL) compared to normal weight group (2.56 ± 0.24 mg/dL, P<0.001), while the dietary intake of magnesium (adjusted for calorie intake) was higher in overweight group (0.20 ± 0.06 mg/ kcal) compared to normal weight (0.17 ± 0.05 mg/kcal; P= 0.005). Serum magnesium levels were inversely correlated with body mass index, systolic blood pressure, diastolic blood pressure, waist circumference and fasting insulin levels. Conclusions: Serum magnesium levels were significantly lower in overweight children compared to those with normal weight in spite of a higher dietary intake.