Eating a protein-rich snack before a meal makes you feel full, but this feeling is not caused by the release of three specific gut hormones. Instead, it may result from the stomach stretching or...

Consuming a protein-rich drink before a meal reduces feelings of hunger and increases fullness in healthy young men, but introducing fat directly into the upper intestine does not significantly affect these sensations, suggesting that protein's effect on fullness comes from signals originating in the stomach or nerves rather than hormones.

When healthy young men consume protein before a meal and fat is delivered directly to the upper intestine, the total amount of food they eat is not lower than when they consume protein alone. This suggests the two stimuli affect fullness independently, not together.