The Science of Peptides: Why Are They So Common in Cosmetics?
Peptides are short protein fragments made of linked amino acids, and in skin they are studied as components that help transmit signals involved in collagen and elastin production. However, it's important to understand that much of this research is at the cellular or tissue experiment stage, and effects in human clinical trials may be limited or vary significantly between individuals. Whether to pursue procedures or specific home care should be discussed with a specialist.
What Are Peptides?
Peptides are short chain-structured substances formed by linking multiple amino acids, and they are used in various forms, from skincare cosmetics to oral supplements. They are broadly classified into signal peptides, carrier peptides, enzyme-inhibiting peptides, and neurotransmitter-inhibiting peptides, each explained as working through different mechanisms.
Signal peptides are known to transmit signals to fibroblasts in the skin, inducing extracellular matrix-related activity, while carrier peptides are described as delivering trace minerals such as copper into skin tissue. Enzyme-inhibiting peptides are reported to work by suppressing the activity of enzymes that break down collagen and elastin.
- 1신호 전달 활성화TGF-β, MAPK 등 세포 신호 경로 자극
- 2섬유아세포 증식진피 내 섬유아세포 활동 증가
- 3세포외기질 합성콜라겐·엘라스틴·히알루론산 관련 유전자 발현 변화
- 4조직 구조 변화 관찰세포·ex vivo 실험 단계에서 관찰된 변화
Mechanism of Action — Evidence from Cell and Tissue Experiments
The mechanism of action of peptides is mainly explained in relation to the activation of cell signaling pathways such as TGF-β and MAPK. When these pathways are activated, it is reported that fibroblast proliferation and the synthesis of extracellular matrix components such as collagen, elastin, and hyaluronic acid may be promoted.
In fact, in vitro studies have shown that collagen peptides increased the expression of COL1A1, ELN, and VCAN genes in human dermal fibroblasts, with increased collagen expression also confirmed through confocal microscopy observation. Ex vivo experiments using human skin tissue have also reported that collagen peptides induced the production of collagen and glycosaminoglycans.
However, these results were mostly observed at the cell and tissue experiment stage, and it is difficult to conclude that the same intensity of effect would appear when actually applied to or ingested by human skin. This is an important point to consider when understanding peptide ingredients.
Effects and Limitations Observed in Human Studies
In a randomized controlled trial (RCT) involving oral collagen peptide intake, skin moisture significantly increased after 8 weeks, and changes such as increased dermal collagen density and reduced fragmentation of the collagen network were observed starting from week 4, with this trend continuing through week 12.
In another 8-week RCT involving 70 participants, wrinkle depth, height, and visual severity scores improved across several facial areas, and skin elasticity as well as epidermal and dermal moisture and dermal density also improved together. In a 12-week double-blind, placebo-controlled trial using a representative topical peptide ingredient (Matrixyl), significant differences compared to the placebo group were also reported.
However, a systematic review and meta-analysis published in 2026 (19 RCTs, totaling 1,341 participants) found that the overall effect of peptides on wrinkle improvement was only 'modest.' Notably, this effect was mainly observed with oral supplement forms, and it was pointed out that no clear effect was confirmed with the widely used topical serum or cream forms. This suggests that the effectiveness of peptide ingredients can vary considerably depending on formulation, method of use, and individual skin condition.
What to Consider When Choosing Procedures or Products
In dermatology practice, peptides are often used as a supplementary component alongside skin boosters or lifting procedures, or approached as an ingredient in home care cosmetics. However, as discussed above, the level of research evidence varies depending on the ingredient and formulation, so it is advisable to approach any specific product or procedure with the understanding that individual results may vary, rather than expecting a definitive effect.
Since the appropriate approach may differ depending on skin condition, treatment history, and other ingredients used together, whether to undergo a procedure and the specific method should always be decided after consulting with a specialist.
Why Skin Barrier Care Matters During Post-Procedure Recovery
Immediately after receiving skin boosters or lifting procedures that include peptide ingredients, the skin barrier may become temporarily sensitive. During this period, it is generally recommended to avoid irritating ingredients and prioritize soothing and moisturizing care.
Immediately after a procedure, redness or sensitivity may remain, so low-irritation soothing care is known to help, while once recovery has progressed to some extent, intensive moisturizing care to replenish the damaged barrier can be helpful.
Home Care Determines Post-Procedure Recovery
Different stages of care may be needed immediately after a procedure and during the recovery period. The Abzu Cream features a 2-STEP system: STEP 1 Ultra Cera-Rich is designed to help soothe redness and support barrier care right after a procedure, while STEP 2 Hydro Re-Boosting can help with intensive moisturizing care as recovery progresses. However, this is not a substitute for the effects of the procedure itself, but rather a concept meant to support skin condition management during recovery, and results and experience may vary by individual.
Medically reviewed by 아비쥬의원 의료진. (September 10, 2026)