What are common symptoms of Vitamin B12 deficiency?

• A. Pallor, jaundice, glossitis, fatigue, weight loss, paresthesia
• B. Weight gain and hyperactivity
• C. Frequent headaches and blurred vision
• D. Elevated iron and ferritin levels

Answer: (A)

Vitamin B12 is essential for making healthy red blood cells and for proper nerve function. When you don’t have enough B12, red blood cell production becomes defective (megaloblastic anemia), which leads to pallor and fatigue from anemia. The mucous membranes can also become atrophic, causing glossitis, and appetite may decrease, contributing to weight loss. Neurologic involvement is a hallmark, with nerves misfiring and sensations like tingling or numbness (paresthesias) and sometimes more diffuse neurologic symptoms. Jaundice can occur because the defective red blood cells are broken down more rapidly in the marrow, increasing bilirubin.

The listed symptoms in this case—pallor, jaundice, glossitis, fatigue, weight loss, and paresthesias—fit these patterns best. Other options describe features not characteristic of B12 deficiency: weight gain and hyperactivity are not typical; frequent headaches and blurred vision aren’t classic markers of B12 shortage; elevated iron and ferritin levels point away from B12 deficiency and toward other iron-related issues.