The aim of this study was to find correlations between folate and vitamin B₁₂ on baseline damage in white blood cells and their association with smoking, alcohol consumption and ageing. Thirty-six healthy vitamin non-deficient male subjects were selected in a randomized study. Comet assay (SCGE) and micronucleus (MN) assay were used as biomarkers of DNA damage. The amount of DNA damage was correlated with vitamin B₁₂ and folic acid concentration. Positive, but non-significant correlation (canonical R = 0.61; χ²=28.97; P=0.253) was found between micronucleus (MN) frequency or comet assay parameters (SCGE) and five covariates (age, smoking, alcohol consumption, vitamin B₁₂ and folate blood serum concentration). The highest MN frequency was observed in the group with the lowest vitamin B₁₂ concentration (F=3.59; P=0.024). The SCGE assay failed to show significant correlation with vitamin B₁₂ or folic acid concentration. Concentration of vitamin B₁₂ was significantly correlated with incidence of micronuclei. Our results present background data that could be valuable for future genotoxicological monitoring.