Vitamin D status in children in the South Marmara Region in Turkey

Aim: The aim of our study was to investigate the age, gender and seasonal differences in vitamin D levels in children and to determine the prevalence of vitamin D deficiency. Materials and Methods: Between January 2022 and December 2023, the records of children aged 0-17 years who underwent serum 25-hydroxyvitaminD (25 (OH) D) levels in the pediatric outpatient clinics of our hospital were retrospectively reviewed. Children were divided into four groups according to age (0-1, 2-5, 6-11 and 12-17 years); three groups according to 25 (OH) D levels (vitamin D deficiency (below 12 ng/mL), vitamin D insufficiency (between 12-20 ng/mL) and vitamin D sufficiency (above 20 ng/mL)); and four groups according to seasons. Results: The 25(OH)D levels of 41899 children, 19738 (47.1%) boys and 22161 (52.9%) girls, was 18.6 ng/mL (3-145); and was lower in girls than boys (16.8 ng/mL (3-136) in girls and 20.3 ng/mL (3-145) in boys p