Dietary peptides from protein digestion induced satiety in rats through both CCK-A receptors and peripheral opioid receptors, with different proteins generating different satiety signal combinations.
Two satiety pathwaysProtein digestion activates both CCK and opioid satiety signals — and the ratio varies by protein source, meaning food choice affects HOW you feel full
What the researchers found
Dietary peptides from protein digestion induced satiety through both CCK-A and peripheral opioid receptor pathways, with the relative contribution of each pathway varying by protein source — different foods activate different satiety signals.
Why it matters
Understanding which satiety signals different proteins activate could guide dietary recommendations for weight management — choosing protein sources that maximize satiety through multiple pathways.
How the study worked
Animal feeding study in rats. Dietary protein digests from different sources administered. Food intake measured with and without CCK-A receptor antagonist (devazepide) and peripheral opioid antagonist (naloxone methiodide).
What this study cannot tell us
Rat feeding study. Protein digestion in vitro may differ from in vivo. The specific peptide fragments responsible for each pathway were not identified.
How to read the evidence
Moderate evidence from a controlled rat feeding study with selective receptor blocking to dissect satiety pathways.
When this study was published
Published in 2002. Dietary peptide satiety signaling has been further characterized, supporting high-protein diets for weight management.
The bigger picture
Diet isn't just about calories — the specific peptides released during digestion actively communicate with the brain through multiple satiety pathways. Optimizing dietary protein sources for maximal satiety signaling is a science-based weight management strategy.
Questions still open
- Which protein sources produce the strongest combined satiety signals?
- Can specific bioactive peptides be isolated for satiety supplementation?
- Does chronic high-protein diet alter satiety pathway sensitivity?
Common questions
Does the type of protein matter for feeling full?
How can this help with weight management?
Read the original research
Dietary peptides induce satiety via cholecystokinin-A and peripheral opioid receptors in rats.
The Journal of nutrition, 132(9), 2775-80
Citation
Pupovac, Jelena; Anderson, G Harvey. (2002). Dietary peptides induce satiety via cholecystokinin-A and peripheral opioid receptors in rats.. The Journal of nutrition, 132(9), 2775-80.