Question:easy
Gastrectomy patient needs supplemental: (PART A)
Gastrectomy patient needs supplemental: (PART A)
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No stomach = no parietal cells = no intrinsic factor, and intrinsic factor is needed only for vitamin B12.
Updated On: Jun 22, 2026
- Vit c
- Vit d
- Vit b12
- Vit a
Show Solution
The Correct Option is C
Solution and Explanation
Ask what the stomach uniquely contributes.
The stomach is dispensable for digesting most nutrients, but it has one absorptive job no other organ can replace: its parietal cells make INTRINSIC FACTOR, the carrier molecule that vitamin B12 must be bound to before the terminal ileum will take it up.
Consequence of removing the stomach.
Gastrectomy excises the parietal-cell mass, so intrinsic factor secretion ceases. Even with a normal diet, B12 now passes through the gut unabsorbed. Hepatic B12 stores buffer this for a couple of years, after which the patient develops megaloblastic anaemia and neurological injury (subacute combined degeneration). The fix is to bypass the gut entirely with intramuscular B12 for life.
Why the other vitamins are safe.
$\bullet$ Vitamin C is water-soluble and absorbed along the small bowel independent of the stomach.
$\bullet$ Vitamins A and D are fat-soluble and absorbed in the small intestine with bile salts, not via any gastric factor.
None of these three relies on intrinsic factor, so none is specifically threatened by gastrectomy.
Answer.
The vitamin that absolutely requires gastric intrinsic factor, and therefore must be supplemented after gastrectomy, is vitamin B12 (C).
The stomach is dispensable for digesting most nutrients, but it has one absorptive job no other organ can replace: its parietal cells make INTRINSIC FACTOR, the carrier molecule that vitamin B12 must be bound to before the terminal ileum will take it up.
Consequence of removing the stomach.
Gastrectomy excises the parietal-cell mass, so intrinsic factor secretion ceases. Even with a normal diet, B12 now passes through the gut unabsorbed. Hepatic B12 stores buffer this for a couple of years, after which the patient develops megaloblastic anaemia and neurological injury (subacute combined degeneration). The fix is to bypass the gut entirely with intramuscular B12 for life.
Why the other vitamins are safe.
$\bullet$ Vitamin C is water-soluble and absorbed along the small bowel independent of the stomach.
$\bullet$ Vitamins A and D are fat-soluble and absorbed in the small intestine with bile salts, not via any gastric factor.
None of these three relies on intrinsic factor, so none is specifically threatened by gastrectomy.
Answer.
The vitamin that absolutely requires gastric intrinsic factor, and therefore must be supplemented after gastrectomy, is vitamin B12 (C).
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