The brain pathway may be more significant than the endocrine route for the physiological effects of GLP-1, especially regarding insulin release, but the endocrine route becomes more pronounced with bigger meals and more L-cell activation (Deacon 2019)
The gut also makes many messenger chemicals used by the brain
I kind of liken it to what were going through with cryptocurrency and the legacy financial system. Opt Health doctors use phrases like buyer beware, nascent industry, and kind of rogue right now. Peptides prescribed by wellness clinics are made and sold by compounding pharmacies with minimal standardization
This is particularly valuable during dose titration when you might want to increase by 1.25 mg increments rather than the standard 2.5 mg jumps
Serotonin is the brain chemical messenger closely tied to mood regulation
found decreased D-lactate, LPS, and diamine oxidase Citation83,Citation132 Perraudeau & McMurdie et al