Which nutritional deficiency is commonly required to be supplemented after gastrectomy due to malabsorption?

Which nutritional deficiency is commonly required to be supplemented after gastrectomy due to malabsorption?

• A. Vitamin C deficiency requiring ascorbic acid supplements
• B. Vitamin D deficiency requiring ergocalciferol
• C. Vitamin B12 deficiency requiring monthly injections or iron and calcium supplementation
• D. Thiamine deficiency requiring thiamine pills

Answer: (C)

After gastrectomy, loss of stomach acid and intrinsic factor impairs vitamin B12 absorption, because intrinsic factor—needed for B12 uptake in the ileum—is produced in the stomach. Without it, B12 deficiency develops and is best treated by lifelong replacement given by injections (typically monthly) to bypass the need for intrinsic factor. Iron and calcium supplements may be needed in some patients due to altered absorption, but the deficiency most specifically and commonly required after gastrectomy is B12, addressed with monthly injections.

After gastrectomy, loss of stomach acid and intrinsic factor impairs vitamin B12 absorption, because intrinsic factor—needed for B12 uptake in the ileum—is produced in the stomach. Without it, B12 deficiency develops and is best treated by lifelong replacement given by injections (typically monthly) to bypass the need for intrinsic factor. Iron and calcium supplements may be needed in some patients due to altered absorption, but the deficiency most specifically and commonly required after gastrectomy is B12, addressed with monthly injections.