In healthy older adults, eating a high-fat diet for 14 days that significantly increases calorie and fat intake does not change the levels of cholecystokinin in the blood after fasting.

A 14-day high-fat diet increases total calorie intake by about 41% in healthy older adults, but does not change baseline levels of the hormone cholecystokinin or its ability to reduce appetite when administered externally.

A two-week high-fat diet does not change how effectively the hormone CCK-8 reduces hunger in healthy older adults, as measured by how much food they eat afterward.

When healthy older adults receive a specific dose of the hormone CCK-8 through an IV, they eat about 11% less food afterward, no matter what they ate before.

In older adults, eating a high-fat diet does not reduce the ability of the hormone cholecystokinin-8 to signal fullness after eating.