Peptides: What They Are and Why They Are Used in Cosmetics

Everything you need to know

There are 3 types of peptides:

1. SIGNALING PEPTIDES: These are typically peptides that can stimulate collagen synthesis and/or reduce its breakdown;
2. ANTI-WRINKLE NEUROTRANSMITTER-MODULATING PEPTIDES: They reduce or block the transmission of nerve impulses that allow muscles to contract, preventing or smoothing out wrinkles
3. METAL-CHELATING PEPTIDES: A certain beneficial effect is achieved through metal chelation.

Of peptides in cosmetics there are countless peptides, each with its own unique function and ability to target different skin concerns: wrinkles, dark circles, puffiness, skin discoloration, and facial redness.

It is up to the cosmetic formulator, after rigorous research, to choose which peptides to include in a formula and how to create a specific synergy with other peptides or functional ingredients.

Peptides for facial Skin

What peptides are used in SKIN FIRST® formulas?

1. PALMITOYL TRIPEPTIDE-5 (Syn®-Coll): A tripeptide that helps slow the cutaneous aging process. It is engineered to prevent the formation of wrinkles and reduce their appearance. It delivers its effects through a dual mechanism: first, it stimulates collagen synthesis by mimicking the action of the TGF-β growth factor, a core component of collagen production. Second, it protects existing collagen from breakdown by inhibiting matrix metalloproteinases (MMPs). Both functions work in tandem to maintain the structural integrity of the Skin. It also helps improve Skin texture and minimize the appearance of enlarged pores.
2. PALMITOYL TRIPEPTIDE-38 (Matrixyl Sinthe® '6): A tripeptide that stimulates the synthesis of the 6 main components of the skin matrix and dermo-epidermal junction (collagen I, III, IV, fibronectin, hyaluronic acid, and laminin 5), resulting in a significant three-dimensional reduction of wrinkles and a smoothing of skin texture.
3. ACETYL HEXAPEPTIDE-8 (Reproage®): It modulates levels of microRNA-145, which plays a role in regulating epidermal cell differentiation. Through this mechanism, Reproage® can trigger cellular reprogramming in the basal layer of the epidermis to extend its natural self-renewal capacity. This results in a reduction in visible signs of aging and a more luminous, glowing Skin.

Biomimetic peptides and natural peptides: what's the difference?

As we've seen, there are countless peptides used in the cosmetics industry. Specifically, the so-called biomimetic peptides, are peptides created synthetically in a lab to mimic the action of natural peptides. It is no coincidence that the name carries this exact meaning: "bio" means "life" and "mimetic" means "that imitates". So if the peptides used in Skin products are biomimetic, what are natural peptides? As outlined earlier, peptides are substances made up of amino acid sequences and act as chemical messengers—molecules that send our bodies very specific signals for actions to carry out; in particular, they drive the production of collagen, elastin, and keratin. They occur naturally in the human body, and also exist in all living organisms worldwide: for example, natural peptides can be extracted from certain types of plankton, or from moss. They can also be found in a wide range of foods, from meat to shellfish to soy. In cosmetics, biomimetic (laboratory-created synthetic) peptides are the most widely used, because they are easier to formulate into Skin care products.

Can peptides cause side effects?

One of the top concerns when discussing products to apply to the Skin is the risk of potential issues linked to their use: products that Peptide-based products can cause side effects? The answer is yes, though only very rarely. Specifically, potential side effects can include sensitivity, rashes, and itching. In extremely rare cases, peptides may trigger allergic reactions. To avoid unexpected issues, we always recommend consulting a dermatologist or another trusted medical source to confirm that any product you use is legitimate and safe, and to test any new product first on a small patch of Skin to ensure it does not cause an allergic reaction.

Peptides in the Eye Contour Gel: what is the specific benefit for this area?

If you've researched the benefits of peptides online, you likely already know that this is one of the most popular methods for treating under-eye puffiness and dark circles.


This effectiveness stems from the fact that one of the key causes of under-eye puffiness and dark circles is collagen loss in the area, which is often age-related. And the action of peptides—protein-like compounds made of amino acids—is precisely to stimulate the body to produce more collagen, smoothing and repairing the Skin. It is no coincidence that the Eye Contour Gel SKIN FIRST It contains peptides with vasoprotective, decongestant, anti-aging, and hydrating properties to help prevent and reduce the appearance of dark circles and under-eye puffiness.

Viper peptide in cosmetics: fact or fiction?

One fun fact about peptides relates to the so-calledviper serum peptide: is this a real ingredient or a fanciful invention to sell more products? The truth is that the so-called viper peptide is indeed an ingredient used in cosmetics thanks to its properties related to inhibiting muscle contractions — in practice, just like snake venom, this peptide immobilizes the area it acts on, limiting wrinkle formation. However, this is not a true viper venom extract, but rather a synthetic compound created in a lab to mimic the action of the natural peptide produced by the reptile: while the latter contains a complex toxin, the venom from the Wagler's pit viper or Temple viper — the so-called viper venom used in cosmetics — only uses the single peptide and its immobilizing action, without any of the other characteristics of full venom. This is therefore a synthetic version of just the natural peptide contained in the venom — not a substance extracted from viper serum — used to inhibit the facial muscle movements that cause wrinkle formation.