Pernicious anemia is associated with vitamin B12 deficiency in the body. This deficiency can be because of the lesser uptake of vitamin B12 in food or the malabsorption of vitamin B12 in the intestines. Vitamin B12 deficiency leads to decreased production of red blood cells. People having malnutrition and intestinal issues with the absorption of vitamin B12 are at risk of developing this type of anemia. Vitamin B12 supplements and dietary modifications are defined to improve the condition.