The aim of this study was to evaluate the vitamin B-12 status in a non-vegetarian sample of the adult urban population from Romania. The studied sample included 80 non vegetarian subjects aged between 19 and 74.6 years who did not use vitamin B-12 supplements or vitamin B-12 fortified food. The serum vitamin B-12 assay was performed using electrochemiluminescence immunoassay on a Roche Elecsys 2010 analyzer. Among all subjects, 93.75% (95% CI 86.2-97.3%) had serum vitamin B-12 concentrations in the reference range of the employed method (191-663 pg/ml). In these subjects, we found no statistically significant correlations between serum vitamin B-12 concentration and age or between serum vitamin B-12 concentration and hemoglobin level. The serum vitamin B-12 levels did not differ significantly (p>0.05-Student's t-test) between women and men. Subnormal serum levels of vitamin B-12 were observed in 5% (95% CI 1.96-12.16%) of the investigated subjects, associated with irritable bowel syndrome and with long-term therapy with proton pomp inhibitors or birth control pills. In the present study, we have identified a large number of subjects with marginal depletion of vitamin B-12 in the population aged below 50 years. These results suggest the need of a screening for vitamin B-12 status in people from all age groups, the importance of the identification of responsible causes for the high prevalence of vitamin B-12 marginal status, as well as the fact that monitoring the vitamin B-12 status is especially important in subjects undergoing long-term treatment with certain drugs.