Prevalence of vitamin B12 deficiency in healthy Indian school-going adolescents from rural and urban localities and its relationship with various anthropometric indices: a cross-sectional study

BackgroundMicronutrient deficiency is a global health burden, especially among developing countries. The present cross-sectional study aimed to determine the prevalence of vitamin B-12 deficiency in healthy Indian school-going adolescents, based on area of residence, sex and body mass index (BMI). Furthermore, the relationship of serum B-12 concentration with dietary vitamin B-12 intake and anthropometric indices was assessed among adolescents from rural and urban India. MethodsA total of 2403 school-going adolescents (11-17years) from National Capital Region and rural areas of Haryana, India were selected. Serum B-12 concentrations were estimated using an electrochemiluminescence immunoassay. Dietary assessments were conducted on 65% of total participants (n=1556) by two 24-h diet recalls. ResultsThe prevalence of vitamin B-12 deficiency in the total study population was 32.4% (rural: 43.9% versus urban: 30.1%, P<0.001; male: 34.4% versus female: 31.0%, P<0.05; normal weight: 28.1%, versus overweight: 39.8%, versus obese: 51.2%, P<0.001). More than half (51.2%) of obese adolescents were vitamin B-12 deficient. On multiple linear regression analysis, serum B-12 in rural adolescents was associated with age (=-0.12, P<0.05). Among urban adolescents, serum B-12 was associated with BMI (=-0.08, P<0.05) and adjusted dietary vitamin B-12 intake (=0.14, P<0.001). Serum vitamin B-12 levels were found to be lower in rural females (=-0.12, P=0.030) and urban males (: 0.11, P<0.001) compared to their respective contemporaries. ConclusionsVitamin B-12 deficiency was higher among rural school-going adolescents. Boys had a higher B-12 deficiency than girls. Inverse associations of serum B-12 with adiposity indices were observed. Serum B-12 levels were positively associated with dietary vitamin B-12 intake.