Trials 18 (1), 432
Retinol and its derivatives work by accelerating cell turnover through vitamin A signaling pathways and often cause irritation, especially during initial use
10.1159/000021313 Boebel KP, Baker DH: Blood and liver concentrations of glutathione, and plasma concentrations of sulfur-containing amino acids in chicks fed deficient, adequate, or excess levels of dietary cysteine
This means oral BPC-157 capsules can reach the gastric and intestinal mucosa in their intact, pharmacologically active form, unlike insulin, growth hormone, or GLP-1 analogs (unless specially formulated), which are immediately destroyed by gastric acid
doi:10.1016/j.ymgme.2013.03.011, PMID: 23583222 Salmi H, Leonard JV, Rahman S, Lapatto R (2012) Plasma thiol status is altered in children with mitochondrial diseases
Each peptide in the Repair & Glow protocol targets a different part of the healing and regeneration process