BPC 157 Benefits: What It Does for Gut, Joints, Muscle, and Recovery BPC 157 is one of the peptides that has been getting a lot of attention recently. It is a synthetic peptide derived from a protein found in human gastric juice. In experimental research, Musculoskeletal and Tissue Healing with BPC 157: Weight Loss and Vitality: Medical Weight Loss Peptide Series #2 BPC 157 Your body already makes this peptide. BPC 157 is naturally found in your gastric juice it's part of how your gut protects itself. Scientists isolated it,