Obez ve Normal Ağırlıktaki Adolesanların Serum Vitamin D Düzeyleri ile Beslenme Durumları ve Biyokimyasal Parametreler Arasındaki İlişkinin Karşılaştırılması

Abstract

The case-control study was planned and implemented with the purpose of determining theserum 25-hydroxy vitamin D level of healthy and obese adolescents and determining the dietary and environmental factors which may affect the serum 25-hydroxy vitamin D level. The research was carried out with 39 obese (BKI>95.th percentile) and 30 nonobese subjects who applied Marmara University Hospital Pendik Educational Research Hospital Pediatric Endocrinology Department aged between 12 and 17 years. Data was collected in three stages; in the first stage, the questionnaire was developed including the demographic status, nutritional status and habits, physical activities of adolescents. In the second stage, anthropometric measurements (weight, height, waist circumference) and body composition analysis were taken. In the third stage, biochemical analysis (serum 25 hydroxy vitamin D, total calcium, iPTH, total-cholesterol, triglycerides, and HDL-cholesterol) was measured. There was no statistical differences between obese serum 25(OH)D (16.2±6.2 ng/ml) and nonobese (18.1±5.9 ng/ml) serum 25(OH)D (p>0.05). Serum 25(OH)D level was lower than 25 ng/L in all adolescents. Statistically not significant inverse relationship was found between serum 25(OH)D level and antropometric mesurements (BMI, fat mass, percentage of body fat and waist circumference) in both groups. While there was no significant difference between serum 25(OH)D levels and HOMA-IR; there was a positive correlation between serum calcium and HOMA-IR (r=0.276 p<0.05). The sources of vitamin D from daily food consumption were egg (%57) and margarine (%18). There was a positive correlation between serum 25(OH)D levels and amount of daily calcium (r=0.371) and phosphorus (r=0.438) (p<0.05). Further more detailed studies taking large case series, in longer periods of time are necessary to explore the relation between serum vitamin D levels and insulin resistance and BMI.