BACKGROUND: Asymptomatic Indian lacto vegetarians, who make up more than half of the Indian population in different geographic regions, have distinctly low vitamin B-12 concentrations than non- vegetarians. Vegetarians consume milk but it seems that the amount is not enough to improve vitamin B-12 status or vitamin B-12 concentration in milk itself may be low. The aim of this study was to determine if daily milk consumption can improve vitamin B-12 status. METHODS: Fifteen male and 36 female, young healthy post-graduate volunteers participated. Blood from ten participants (4 males and 6 females) was collected (day-1). They continued their regular diet for next fourteen days and on day-15, blood of all 51 participants was collected, plasma vitamin B-12 concentration was measured and were divided into two groups; Normal (vitamin B-12 >148 pmol/L, n = 22) and Vitamin B-12 deficient (<148 pmol/L, n = 29), the remaining plasma was stored. All participants consumed 600 ml. of non-enriched buffalo milk (200 × 3) during the day along with their usual diet. Next day blood was collected for plasma holotranscobalamin II measurement. Subjects from deficient group continued to drink 400 ml of milk daily for next 14 days and blood was collected on day-30. Plasma holotranscoabalamin II (day-1, 15, 16, 30), vitamin B-12, folate, total homocysteine, creatinine and hematoloical parameters (day-1, 15, 30), and milk vitamin B-12 concentrations (day-15, 16, 30) were measured. RESULTS: Fifty seven per cent of the participants were vitamin B-12 deficient and 65% were hyperhomocysteinemic. No significant difference in biomarkers was observed when there was no intervention. Plasma holotranscobalamin II concentration increased from 19.6 to 22.27 pmol/L (p < 0.0001) 24 hrs after milk load in the whole group. Plasma vitamin B-12 increased from 92.5 to 122 pmol/L and tHcy concentrations decreased from 31.9 to 24.9 µ mol/L (p < 0.0001 for both) 14 days after regular milk intake in vitamin B-12 deficient subjects. CONCLUSIONS: Regular intake of milk improved vitamin B-12 status of vitamin B-12 deficient vegetarians indicating a potential dietary strategy to improve the vitamin status.