Ileocecal valve resection can lead to malabsorption due to which mechanism?

• A. Decreased transit time and influx of nutrients into the large intestine
• B. Increased transit time and slower flow into colon
• C. Increased water absorption in colon
• D. No effect on absorption

Answer: (A)

Removing the ileocecal valve removes a key brake that slows the passage of content from the ileum into the colon. Without that control, transit through the small intestine speeds up, giving less contact time for nutrients to be absorbed. As a result, more nutrients reach the large intestine before they are fully absorbed, which leads to malabsorption. The colon ends up handling a larger load of undigested nutrients, which can cause osmotic effects and contribute to diarrhea, further reflecting the impaired overall nutrient uptake. The other ideas don’t fit because slower flow into the colon, greater water reabsorption in the colon, or no change in absorption don’t explain how rapid transit after valve removal reduces absorption in the small intestine.