Which deficiency is commonly linked to anemia in many populations?

• A. Iron deficiency
• B. Vitamin B12 deficiency
• C. Folate deficiency
• D. Vitamin C deficiency

Answer: (B)

Iron deficiency is the deficiency most commonly linked to anemia in many populations. Hemoglobin—the molecule in red blood cells that carries oxygen—depends on iron. When iron intake is low, absorption is poor, or there is blood loss, the body can’t make enough hemoglobin. That leads to fewer red blood cells that are smaller and lighter in color (microcytic, hypochromic anemia), causing fatigue and reduced oxygen delivery. This pattern is the most widespread cause of anemia worldwide, affecting children, women of childbearing age, and people in groups with limited diets or high rates of blood loss.

Vitamin B12 deficiency, while it causes a different type of anemia (megaloblastic anemia with larger red blood cells and potential neurologic symptoms), is not as globally common. Folate deficiency can cause a similar megaloblastic anemia but is also less prevalent than iron deficiency. Vitamin C deficiency can contribute to health problems and can affect iron status to some extent, but it is not a primary or common cause of anemia.

So, the deficiency most commonly linked to anemia across many populations is iron deficiency.