Reference definition
National Human Genome Research Institute. Peptide. Talking Glossary of Genomic and Genetic Terms. ↗A definition of peptides as short amino-acid chains.
Explore the sources
Sources & evidence
The sources behind our stories: definitions, guides, and studies. Each entry explains what kind of evidence you are reading.
7 explore the sources
Research guide
National Institutes of Health. Understanding Clinical Studies. Reviewed June 26, 2025. ↗Explains observational studies, randomized trials, and what different designs can answer.
Systematic review
Vasireddi N, et al. Emerging Use of BPC-157 in Orthopaedic Sports Medicine: A Systematic Review. HSS J. 2025;21(4):485–495. ↗A review of 36 studies, predominantly preclinical, identifying limited clinical and safety evidence.
Review
Anisimov VN, Khavinson VKh. Peptide bioregulation of aging: results and prospects. Biogerontology. 2010;11(2):139–149. ↗A historical review of peptide preparations in aging research, including rodent experiments and clinical observations.
Laboratory and animal research
Lee C, et al. The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance. Cell Metab. 2015;21(3):443–454. ↗Describes MOTS-c and experimental metabolic findings, including mouse studies. It does not establish a personal-use outcome.
Review
Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018;19(7):1987. ↗A review of GHK-Cu research, including tissue-remodelling and gene-expression findings. Not a test of a particular finished cosmetic.
Animal research and human trial
Gong J, et al. Walnut peptide and theanine combination ameliorates sleep disorders: a multi-species study including a human trial. Food Funct. 2026;17(3):1199–1213. ↗Studies a walnut-peptide/theanine combination, including an eight-week placebo-controlled human trial. It does not isolate the peptide's contribution.
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