摘要："Introduction: Tobacco consumption is risk factor for so many diseases. Experimental and clinical evidence both suggest that there is some connection between metabolism of vitamin B12 and that of cyanide. Smoking releases cyanide and other toxins. Methods: In this study out of 120 patients 40 were smokers, 40 were tobacco chewers and 40 were nontobacco users in any forms (controls).Prospective case control study was done. Measurement of serum Vitamin B12 level was done. The patients having Vitamin B12 level 210pg/ml were considered normal. Serum Vitamin B12 level was done using radio immune-essay by Immulite analyzer. Results: It was seen that in tobacco consuming patients vitamin B12 levels in serum were low. The 69% patients with vegetarian diet and 37% patients with mixed diet were having Vitamin B12 deficiency. Odds ratio of 3.87 is suggesting that Vitamin B12 deficiency was quite common in Vegetarian diet. Conclusions: The association between tobacco use and vitamin B12 deficiency was found statistically significant. So correlation can be there. However large study required."
