Articles

Several peptides studied in metabolic contexts — including BPC-157, GLP-1 analogues, and certain GH secretagogues — show effects on insulin sensitivity, but through different mechanisms and with very different evidence quality. Grouping them as 'peptides that improve insulin sensitivity' obscures more than it reveals.

GH-releasing peptides (GHRPs and GHRHs) are strongly inhibited by insulin. Administering them in the post-workout window — when carbohydrate intake spikes insulin — significantly blunts the GH pulse they would otherwise produce. Timing these peptides in a fasted or low-insulin state is essential for efficacy.

Fasting state appears to enhance BPC-157's gut healing effects based on animal data, likely because reduced luminal content allows greater mucosal contact and the fasted metabolic state upregulates repair pathways BPC-157 amplifies. No human studies have directly tested this interaction.