Start with the ingredient list
The front of a serum bottle may give you a trade name or say “peptide complex.” The ingredient list gives you names you can look up. For example, The Ordinary lists Copper Tripeptide-1 in its US copper peptide serum. Check the packaging for your own product because labels can vary by region and formula revision.
Manufacturer ingredient listThe Ordinary · Multi-Peptide + Copper Peptides 1% Serum
Match the claim to the study
A 12-week study compared a moisturizer containing palmitoyl pentapeptide with the same base moisturizer in 93 white women ages 35–55. The authors reported an improvement in the appearance of fine lines and wrinkles for the studied formula. The study tested one peptide in one formula, and the authors were affiliated with a manufacturer. For a different serum, look for evidence on that formula.
Primary human study · manufacturer-affiliatedRobinson et al. · Palmitoyl pentapeptide in a facial moisturizer
Keep the cosmetic claim in view
This reference covers topical beauty products and claims about how skin or hair looks or feels. In the US, intended use helps determine whether a product is a cosmetic, a drug, or both. Claims to treat disease or change how the body works have a different regulatory standard.
US regulatorFDA · Cosmetic and drug claims