Riboflavin is in the vitamin B group. The main type of vitamin B deficiency anemia is pernicious anemia. Pork is very high in thiamin (vitamin B). The liver is the site for vitamin B metabolism. Symptoms of deficiency are similar to other vitamin B deficiencies. Its chemical structure resembles that of pyridoxine (a type of vitamin B). Pellagra is a disease caused by a lack of the vitamin niacin (vitamin B). Thiamine deficiency is a medical condition of low levels of thiamine (vitamin B). Tinnitus may be associated with vitamin B deficiency. Phenelzine has also been linked to vitamin B deficiency. Pyridoxine is in the vitamin B family of vitamins. Primary metabolite enzymatic cofactors include members of the vitamin B family. Symptoms also appear to be dependent on the form of vitamin B taken in supplements. Hyperhomocysteinemia is typically managed with vitamin B, vitamin B and vitamin B supplementation. The human physiology of active vitamin B absorption from food is complex.