Cholecystokinin (CCK) is a digestive hormone released with secretin when food from the stomach moves to the duodenum. Cholecystokinin improves digestion and functions as a hunger suppressant by activating the satiety center of the hypothalamus in the brain. If cholecystokinin were not released after eating a fatty meal, the person will not feel full and may eat more fat than what the body requires. This can result in health problems.