Which vitamin deficiency can lead to pernicious anemia?

Pernicious anemia is primarily caused by a deficiency of vitamin B12. This vitamin is essential for the production of red blood cells and the proper functioning of the nervous system. In pernicious anemia, the body's ability to absorb vitamin B12 from the intestinal tract is disrupted, often due to the lack of intrinsic factor, a protein produced by the stomach that is necessary for vitamin B12 absorption.

Without adequate vitamin B12, DNA synthesis is impaired, leading to the formation of large, dysfunctional red blood cells—this condition is termed megaloblastic anemia. The symptoms of pernicious anemia can include fatigue, weakness, pale skin, heart palpitations, and neurological issues, such as numbness or tingling in the hands and feet.

While other vitamins are crucial for various body functions—such as vitamin A for vision and immune function, vitamin C for collagen synthesis and antioxidant activities, and vitamin D for calcium absorption and bone health—none of them are linked to pernicious anemia as closely as vitamin B12 is. Therefore, a deficiency in vitamin B12 is unmistakably identified as the cause of this type of anemia.