Research
Mixed
Vagal afferent signaling regarding food intake is primarily driven by mechanoreceptors (IGLEs) sensing intestinal stretch, rather than chemoreceptors sensing gut peptides like GLP-1.
When taking GLP-1 medications, part of the weight loss comes from the physical feeling of fullness (stretch) in your stomach and intestines, not just a chemical signal. This is why you feel full faster and stay full longer. The drug enhances these mechanical signals to your brain.
GoodRefutesMEDIUM confidence
Williams et al. demonstrated that contrary to expectations, subsets of VANs containing GLP-1 receptor (GLP-1R) detected stomach and intestinal stretch and, interestingly, had no impact on nutrient sensing... only activation of Oxtr-containing neurons, exclusively intestinal IGLEs that detect stretch, potently suppressed food intake, while various subtypes of mucosal ending neurons, which are classically thought to sense gut peptides, had no effect.
Why this rating
Based on recent optogenetic/chemogenetic studies cited, though the paper notes some contradictory findings.
Source
Role of the gut–brain axis in energy and glucose metabolism
Hallie R. Wachsmuth et al. · Experimental & Molecular Medicine · 2022
DOI 10.1038/s12276-021-00677-w
narrative_reviewCited 243×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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