How are dietary fats processed after absorption?

• A. They are remade into triglycerides and enter the lymphatic system.
• B. They enter the portal vein directly to the liver.
• C. They are excreted in stool.
• D. They are converted to glucose.

Answer: (A)

After absorption, dietary fats are reassembled into triglycerides inside enterocytes and packaged with cholesterol, phospholipids, and apolipoproteins into chylomicrons. These particles are large and enter the lymphatic system through the intestinal lacteals, bypassing the liver at first. The lymph then drains into the thoracic duct and into the bloodstream via the left subclavian vein. In tissues, an enzyme called lipoprotein lipase breaks down the triglycerides in chylomicrons to release fatty acids for use or storage, and the remnants are eventually cleared by the liver. Short-chain fatty acids, by contrast, are absorbed directly into the portal circulation, but the typical pathway for dietary fats involves the lymphatic route.