What is the role of bile in digestion and what is enterohepatic circulation?

• A. Bile salts emulsify fats and are recycled to the liver via enterohepatic circulation from the ileum to the liver.
• B. Bile salts digest starches in the small intestine.
• C. Bile salts are only produced after meals and excreted in urine.
• D. Bile salts emulsify fats and are excreted in the colon.

Answer: (C)

Bile salts play a key role in fat digestion by emulsifying fat. This means they coat fat droplets and break them into tiny pieces, increasing the surface area for pancreatic lipase to work effectively. Enterohepatic circulation describes how these bile acids are reused rather than discarded. After helping digest fats, most bile salts are reabsorbed in the terminal ileum and travel via the portal vein back to the liver, where hepatocytes take them up and secrete them again into bile. This recycling conserves bile acids so new production is needed only to replace the small amount lost in feces each day. Bile salts do not digest starches, they are not produced only after meals, and they are not excreted in urine; while a portion does end up in feces, the primary concept is their recycling through the ileum back to the liver.