[Serum Vitamin B12 Levels in an Adolescent Population in Madrid]

Introduction: Serum vitamin B12 concentration levels in children are essential to establish values in order to compare different regions or countries, and for considering e the possibility of supplementing diets with group B vitamins as a secondary prevention against cardiovascular diseases.

Material And Methods: A cross-sectional epidemiological study was carried out to asses serum vitamin B12 levels in school children, 13-15 years of age, in Madrid. Folate and vitamin B12 vitamin determinations were performed on fasting blood samples. Genotype C677T of methylentetrahydrofolate reductase (MTHFR) enzyme was determined by PCR.

Results: The mean vitamin B12 level obtained in our study was 503 pmol/l; CI 95 % CI (478-528 pmol/l). The median was 471 pmol/l; interquartile range (IR) (337-632 pmol/l). No statistically significant differences were found by age or C677T genotype for MTHFR. Serum vitamin B12 concentrations were significantly higher in females. Prevalence of vitamin B12 deficiency (< 224 pmol/l) was 6 % in males and 4 % in females.

Conclusions: Reference values for serum vitamin B12 concentrations in an adolescent population are presented. Prevalence of vitamin B12 deficiencies is higher in males.