Vitamin D status and its relationship with metabolic syndrome risk factors among adolescent girls in Boukan, Iran.

OBJECTIVE To investigate vitamin D status and its association with components of the metabolic syndrome (MetS) in adolescent girls attending high school in Boukan, Iran during winter 2012. DESIGN A cross-sectional study. SETTING High schools of Boukan city, Iran. SUBJECTS A sample of 216 girls aged 14-17 years was selected by multistage random sampling from four districts of Boukan. Weight, height, waist circumference, blood pressure, daily energy intake, physical activity and serum 25-hydroxyvitamin D (25(OH)D), fasting blood glucose, TAG and HDL-cholesterol levels of all participants were evaluated. Serum 25(OH)D level <20 ng/ml was defined as vitamin D deficiency. RESULTS Mean serum 25(OH)D was 7.26 (sd 2.81) ng/ml and 96 % of the participants had vitamin D deficiency. According to age-modified definitions of the National Cholesterol Education Program Adult Treatment Panel III, MetS was diagnosed in 10.6% of the participants. In multivariable regression analysis after adjustment for BMI, energy intake and physical activity level, serum 25(OH)D was inversely associated with fasting blood glucose (β = -0.143, P = 0.04). No significant relationship was found between serum 25(OH)D and other components of MetS. CONCLUSIONS The high prevalence of vitamin D deficiency warrants national polices and interventions towards improving this major health problem among adolescent girls. Low 25(OH)D level was significantly associated with increased fasting blood glucose. Prospective studies are needed to determine the effects of vitamin D deficiency on the development of MetS and related metabolic diseases in adolescent girls.