What are peptides in skincare?
Peptides are short chains of amino acids — the building blocks of proteins. In skincare, peptides can be categorised into signal peptides, carrier peptides and neurotransmitter-inhibiting peptides. Different peptides play different roles, from stimulating collagen and elastin production, to facilitating biological processes and reducing facial contractions. Peptides are commonly used in anti-ageing skincare and are known for their diverse modes of action.
Different peptides also have different structures and functions. Their ability to influence cellular activity is why they are often described as cell-communicating ingredients.
Traditionally, peptides in skincare have focused on collagen support and visible signs of ageing. But research increasingly recognises that healthy skin depends on more than collagen alone. The skin barrier, immune response and microbiome all contribute to a balanced skin ecosystem. This is where a new generation of peptides is beginning to stand out.
Why the skin microbiome matters
While peptides have traditionally focused on collagen support, skin health also depends on a balanced skin microbiome.
The skin microbiome is the community of microorganisms naturally living on the skin. A healthy microbiome helps support the skin barrier, regulate inflammation and defend against environmental stressors. However, modern lifestyle factors, including pollution, over-cleansing and harsh active ingredients, may affect the skin microbiome.
An imbalanced skin microbiome is associated with skin sensitivity, irritation and compromised barrier function. In other words, even if collagen production is stimulated, the skin may still struggle if its overall ecosystem is disrupted.
The different types of peptides
Peptides are generally classified according to their primary biological function.
| Peptide category | Primary function | Examples |
|---|---|---|
| Signal peptides | Support cellular communication and skin signalling | Palmitoyl Pentapeptide-4, Acetyl Tetrapeptide-2, Acetyl Heptapeptide-4 |
| Neurotransmitter-inhibiting peptides | Influence neuromuscular signalling related to expression lines | Acetyl Hexapeptide-8 |
| Carrier peptides | Deliver trace elements that support skin processes | GHK-Cu |
| Enzyme-inhibiting peptides | Help reduce the breakdown of structural skin components | Certain rice- and soy-derived peptides |
Table 1. Common categories of cosmetic peptides, their primary functions and examples. Source: Bioli, based on scientific literature.
The shift toward next-generation bioactive peptides
Advances in skin biology and biotechnology are expanding the potential role of peptides beyond collagen support. New approaches explore how peptides can be designed to target specific aspects of skin health, including:
- Skin resilience
- Microbiome balance
- Skin barrier integrity
- Inflammatory responses
This reflects a broader shift in skincare: from addressing visible signs of ageing towards supporting long-term skin health. Biotechnology helps researchers develop and investigate peptides with more targeted functions, although their benefits depend on the specific peptide and supporting scientific evidence.
Look for Acetyl Heptapeptide-4
One example of this evolving approach is Acetyl Heptapeptide-4, a signal peptide designed to support:
- Microbiome balance
- Skin barrier integrity
- Skin resilience in urban environments
Rather than focusing solely on visible signs of ageing, this supports the skin ecosystem more holistically. You can learn more about Acetyl Heptapeptide-4 and explore products such as Bioli's Strengthening Serum with the ingredient in here or through INCI Decoder, and get tips on how to read skincare ingredient lists in our article: Unfolding the Ingredients Label: A Guide to Decoding the INCI.
As the need for skincare that supports sensitive skin and long-term skin health grows, microbiome-friendly ingredients are becoming increasingly relevant. Peptides are, as highlighted, evolving beyond their traditional role as “anti-ageing ingredients” towards broader skin health applications, and as research advances, the focus is shifting towards skincare that support the skin ecosystem as a whole. Because healthy skin is not only about collagen. It is also about resilience, diversity and balance.
