What is a major function of bile salts in digestion?

Bile salts play a crucial role in the digestion process, particularly in the emulsification of fats. This function is vital because fats are largely insoluble in water, making it difficult for enzymes to access and break them down efficiently. Bile salts, which are derived from cholesterol and produced in the liver, act like detergents in the digestive system. They surround fat droplets and break them into smaller micelles, increasing the surface area available for lipases (the enzymes that digest fats) to act upon. This emulsification helps facilitate the digestion and absorption of dietary fats and fat-soluble vitamins.

Other functions pertain either to other biochemical processes or occur later in digestion. For example, while bile salts aid in the absorption of fat-soluble vitamins after fats have been emulsified and digested, their primary function is in the emulsification process itself. Breaking down carbohydrates and proteins involves different enzymes and mechanisms, with carbohydrates broken down by amylases and proteins by peptidases, neither of which is directly related to the action of bile salts. Thus, the primary and major function of bile salts is their role in emulsifying fats.