Which hormone helps slow GI motility for digestion of fat and protein?

Cholecystokinin (CCK) plays a crucial role in the digestive process, particularly in the breakdown of fats and proteins. When food enters the small intestine, especially food rich in fats and proteins, the release of CCK is stimulated. One of its primary functions is to slow down gastrointestinal (GI) motility, allowing more time for the thorough digestion and absorption of these macronutrients.

By slowing GI motility, CCK enhances the efficiency of digestive enzymes and bile salts released from the pancreas and gallbladder. This ensures that fats are emulsified properly and that proteins are broken down into smaller peptides and amino acids, promoting better nutrient absorption.

The other hormones mentioned do have significant roles in digestion, but they do not primarily function to slow down GI motility in relation to fat and protein digestion. Insulin, for instance, is more involved in glucose metabolism and does not directly affect GI motility. Secretin regulates water homeostasis and influences the secretion of pancreatic juices but does not directly slow GI motility. Gastrin mainly stimulates gastric acid secretion and gastric motility, rather than slowing it. Hence, cholecystokinin is the hormone that specifically aids in the process of slowing GI motility to optimize the