Objectives The aim of this study was to identify the correlation of obesity with 25-hydroxyvitamin D levels in a population-based sample of schoolchildren Al Ain, United Arab Emirates.
Methods It was a cross-sectional study. A random sample of 1018 adolescents aged 12 to 18 years was selected from 140 Schools. A self-administered questionnaire was used to obtain socio-demographic characteristics, physical activity and dietary habits. Blood samples were collected after overnight fast for more than 8 hours. Blood pressure (BP), height weight, waist and hip circumference measurements were made by trained nurses. Body mass index (BMI) less than 85th, greater than 85th but less than 95th, and ≥95th percentiles for age and gender were used to define normal, overweight and obese according to the 2000 CDC growth charts. Fasting blood glucose and plasma lipids were also measured. Serum 25 (OH) D concentrations were measured in subset of youth aged 15 to 18 years.
Results The age of study participants (n=315) ranged from 15 to 18 years. Overall 13% of the participants had vitamin D deficiency (<15 ng/mL). A high proportion (21%) of female youth had vitamin D deficiency compared to their male counterparts (5%). After adjustment for age, female gender, body mass index was negatively correlated with vitamin D levels (p<0.05).
Conclusion The present findings emphasize the importance of obesity prevention in order to prevent vitamin D defiance. There is significant disparity by gender and vitamin D deficiency prevention programs should particular focus female children.