Though its name does not reveal it, Carnosine is a peptide, a small, two amino acid (β-Ala-His) one. It is naturally present in high concentrations in muscle and brain tissues, but the one used in cosmetic products is biomimetic, meaning that it is synthetically produced in a lab to copy the natural thing. 

A 2017 review paper on topical peptides writes about Carnosine that it is a "well-documented aqueous antioxidant with wound healing activity".  

Other than that we can write about manufacturer-done in-vitro (in the lab, not on real people) studies that show Carnosine to have anti-glycation properties. Glycation is the not-so-nice process that happens when we bombard our body with too much sugar that results in damaged body proteins and eventually in more wrinkles.  

Also, a manufacturer done in vitro study shows that carnosine might have collagen-boosing magic power. However, the 2017 research paper also mentions that even though Carnosine is a small molecule, it is water soluble and does not penetrate the skin past the top layers so we have some doubt if the collagen-boosting works in real life. We could find one anti-aging study made on real people that mentions Carnosine, but it was combined with a bunch of other anti-aging actives so it is pretty much impossible to know what Carnosine did or did not. 

One last thing to mention is that there is also a manufacturer done clinical study (done on real people) that shows carnosine being effective against the damages caused by infrared (IR) radiation. (source)

Show me some proof

  • Schagen, Silke Karin. "Topical peptide treatments with effective anti-aging results." Cosmetics 4.2 (2017): 16.
  • Kaczvinsky, Joseph R., et al. "Efficacy of anti‐aging products for periorbital wrinkles as measured by 3‐D imaging." Journal of cosmetic dermatology 8.3 (2009): 228-233.

Products with Carnosine

EO LABORATORIE` Natural & Organic Moisturizing Facial Tonic Paula's Choice Calm Redness Relief Toner For Normal To Dry Skin Lululun Face Mask Precious White Skin Actives Collagen Serum Skin Actives Antioxidant Serum Ringana Anti-Wrinkle Serum Olay Regenerist 3-Point Treatment Cream UFO Youth Junkie Mask Foreo Paula's Choice Resist Weightless Advanced Repairing Toner DR ROEBUCK’S Boost & Tighten Serum Olay Olay Pro-Retinol Eye Treatment Olay Regenerist 3-Point Super Serum La Roche-Posay Anthelios Spf 50 Mist Medik8 Advanced Day Total Protect La Roche-Posay La Roche-Posay Toleriane Ultra Overnight Moisturiser Olay Luminous Brightening & Protecting Lotion With Sunscreen Broad Spectrum Spf 30 Paula's Choice Resist 10% Niacinamide Booster Skin Actives Vitamin A Cream TRUE BOTANICALS Clear Cellular Repair Serum Kristina Holey + Marie Veronique Micronutrient + Hydro Mask Minon Amino Moist Mask Paula's Choice Resist Retinol Skin-Smoothing Body Treatment Perricone MD Re:Firm Surface Recovery Treatment Institut Esthederm Cellular Concentrate Serum Minon Amino Charge Milk SUNDANCE Anti Pollution Sonnenfluid Skin Actives Restoration Cream StriVectin Active Infusion Youth Serum La Roche-Posay Redermic R Uv Anti-Ageing Cream Spf 30 Skin Actives Anti-Aging Cream Beauty Pie Über Youth Super Serum Institut Esthederm Intensive Aha Peel Gentle Serum Venn Age-Reversing All-In-One Concentrate Paula's Choice Clinical Ceramide-Enriched Firming Moisturizer Hada Labo Premium Hydrating Cream Night Missha Time Revolution Immortal Youth Cream Esthederm Adaptasun Strong Sun