What is the role of bile salts in fat digestion?

• A. They digest proteins
• B. They activate lipase
• C. They emulsify fats into smaller droplets to increase surface area for lipase
• D. They emulsify sugars

Answer: (C)

Bile salts act as detergents in the small intestine, breaking up large fat globules into many smaller droplets. This emulsification greatly increases the surface area of fat exposed to digestive enzymes, so pancreatic lipase can access and hydrolyze triglycerides more efficiently. The lipase then converts fats into fatty acids and monoglycerides, which are transported to the intestinal lining within micelles formed with bile salts for absorption. Bile salts don’t digest proteins, they don’t activate lipase, and they don’t emulsify sugars.