Dietary fat is predominantly absorbed in which region of the gastrointestinal tract?

• A. Ileum and colon
• B. Stomach and duodenum
• C. Duodenum and proximal Jejunum
• D. Distal jejunum and ileum

Answer: (C)

Fat absorption occurs primarily in the small intestine, with the majority happening in the duodenum and proximal jejunum. Bile salts emulsify dietary fats in the lumen, and pancreatic lipase then breaks triglycerides into free fatty acids and monoglycerides. These products form mixed micelles with bile acids, which deliver them to enterocytes for uptake. Inside the enterocytes, fatty acids and monoglycerides are reassembled into triglycerides and packaged into chylomicrons that enter the lymphatic system. This rapid, early section of the small intestine is where most fat absorption takes place; the ileum and colon absorb only small amounts of fat and are more involved in bile acid reabsorption and water/electrolyte handling.