Food intake is regulated by short-term gut signals (CCK, GLP-1, ghrelin) that control individual meals and long-term adiposity signals (leptin, insulin) that regulate body weight over weeks and months.
Two time scalesShort-term gut peptides control individual meals while long-term adiposity signals regulate body weight over weeks — both must be understood for effective obesity treatment
What the researchers found
Appetite regulation involves two integrated time scales: acute meal-by-meal gut peptide signals (CCK, GLP-1, ghrelin, PYY) and chronic body weight signals (leptin, insulin), converging on hypothalamic and brainstem integration centers.
Why it matters
Effective obesity treatment may require targeting both short-term (meal) and long-term (body weight) regulatory systems. Understanding this dual-time-scale architecture guides combination therapy development.
How the study worked
Comprehensive review of peripheral metabolic signaling in food intake regulation, covering gut peptides, adiposity signals, and their central integration pathways.
What this study cannot tell us
Review from 2001. The rapid advances in GLP-1-based obesity drugs since then have validated some predictions while complicating others.
How to read the evidence
Moderate evidence from a comprehensive review integrating decades of appetite physiology research into an organized framework.
When this study was published
Published in 2001. The GLP-1 pathway described here has since produced blockbuster obesity drugs (semaglutide/tirzepatide), validating this framework.
The bigger picture
GLP-1 agonists (semaglutide) have transformed obesity treatment by targeting one short-term signal. The next frontier may involve combining short- and long-term signal modulation for even better results.
Questions still open
- Would combining GLP-1 and leptin therapies produce superior weight loss?
- Does chronic GLP-1 agonism also affect long-term body weight set point?
- Can the two time scales be independently manipulated?
Common questions
Why is losing weight so hard?
How do modern obesity drugs work in this framework?
Read the original research
Peripheral signals conveying metabolic information to the brain: short-term and long-term regulation of food intake and energy homeostasis.
Experimental biology and medicine (Maywood, N.J.), 226(11), 963-77
Citation
Havel, P J. (2001). Peripheral signals conveying metabolic information to the brain: short-term and long-term regulation of food intake and energy homeostasis.. Experimental biology and medicine (Maywood, N.J.), 226(11), 963-77.