Question

Vitamin to be supplemented after gastrectomy?

• A. Vit A
• B. Vit C
• C. Vit B12
• D. Vit D

Hint:

The stomach makes intrinsic factor; only one vitamin needs intrinsic factor to be absorbed.

Answer 1

The Correct Option is C

Step 1: Link gastrectomy to absorption physiology. The stomach's parietal cells secrete intrinsic factor (IF). Vitamin B12 (cobalamin) binds intrinsic factor, and this B12-IF complex is the form absorbed in the terminal ileum.

Step 2: Effect of removing the stomach. After gastrectomy (total, or significant partial), parietal cells are lost, intrinsic factor falls, and dietary B12 can no longer be absorbed despite a normal ileum. Body B12 stores last a few years, so a megaloblastic anaemia/neurological deficiency develops months to years later unless B12 is supplemented (usually parenteral, since the oral IF-dependent route is gone).

Step 3: Select the answer. The vitamin specifically requiring lifelong supplementation after gastrectomy is Vitamin B12 - Option C.

Step 4: Why the others are wrong. (A) Vitamin A is a fat-soluble vitamin absorbed in the small intestine and does not depend on the stomach. (B) Vitamin C is absorbed in the small intestine and is not gastric-dependent. (D) Vitamin D absorption occurs in the small intestine with bile and is unaffected by loss of intrinsic factor. None of these depend on intrinsic factor.

Final Answer: Option C - Vitamin B12.