Hi! Incomplete data! Anyhow, Vitamin B12 deficiency is more commonly seen in pure vegetarians! Other common causes include: Heavy alcohol ingestion Atrophic gastritis, in which your stomach lining has thinned Pernicious anemia, which makes it hard for your body to absorb vitamin B12 Surgery that removed part of your stomach or small intestine, Conditions affecting the small intestine, such as Crohn s disease, celiac disease, bacterial growth, or a parasite Long-term use of acid-reducing drugs. These are some of the common causes of vitamin 12 deficiency. May be you are having the lack of factor which is required for Vitamin B 12 absorption. Consult your doctor to find out the cause in your case.