Which vitamin deficiency can lead to megaloblastic anemia?

Megaloblastic anemia is primarily caused by deficiencies in certain vitamins that play a critical role in DNA synthesis and red blood cell formation. Vitamin B12 is essential for the proper maturation of red blood cells in the bone marrow. When there is a deficiency in vitamin B12, the maturation process of red blood cells is disrupted, leading to the production of abnormally large and immature cells, known as megaloblasts. This results in megaloblastic anemia, characterized by a high mean corpuscular volume (MCV) and low hemoglobin levels in the blood.

Moreover, folate (another B vitamin) deficiency can also lead to megaloblastic anemia, but the question specifically highlights vitamin B12. Vitamin B12 deficiency may also arise due to several factors, including malabsorption conditions (such as pernicious anemia) or dietary insufficiency, particularly in individuals with strict vegetarian or vegan diets who do not adequately consume animal products.

In contrast, the deficiencies in the other vitamins listed—such as Vitamin C, Vitamin D, or Vitamin A—do not directly lead to megaloblastic anemia. Vitamin C is important for collagen synthesis and immune function; Vitamin D is crucial for calcium homeostasis and bone health; and Vitamin A is