The word “peptide” appears often on creams aimed at the look of firmness and fine lines, but on its own it does not tell you which molecule targets what. The types, how two well-known examples work and the limits of the evidence give you enough of a framework to read the label correctly.
In short: Peptides are molecules formed when a few amino acids are linked together in a short chain. One cosmetic review groups them into four categories: signal peptides, carrier peptides, neurotransmitter-affecting peptides and enzyme-inhibiting peptides. Argireline™ (acetyl hexapeptide-8) is aimed at the look of expression lines. Firm Baby Firm contains 4% Argireline™ and 3% Matrixyl™ 3000. The limit of the evidence is skin penetration: a laboratory finding is not the same as the result of a finished cream.
| What it does | Aims to help with the look of fine lines and to support the look of firmness; the evidence varies by peptide |
|---|---|
| When | Firm Baby Firm in the evening, as the last layer after serums |
| Sun protection | Peptides do not replace sunscreen |
| At s'hevec | Firm Baby Firm: 4% Argireline™ + 3% Matrixyl™ 3000; Love In Blue This Time: copper tripeptide-1, a supporting ingredient with no stated concentration |
What is a peptide?
A peptide is a molecule formed when amino acids are linked in a short chain; it is much shorter than a protein. Peptides that occur naturally in the skin act as signalling molecules in processes such as growth, defence and balance (homeostasis); those used in cosmetics are short, stable, synthetic sequences inspired by this mechanism.
What types of peptides are used in cosmetics?
Cosmetic peptides are generally grouped into four categories: signal peptides, carrier peptides, neurotransmitter-affecting peptides and enzyme-inhibiting peptides. This classification comes from the 2021 review by Skibska and Perlikowska; the 2017 review by Pai and colleagues lists structural peptides instead of the enzyme-inhibiting group.
| Type | How it is thought to work | At s'hevec |
|---|---|---|
| Signal peptides | Start a signalling cascade; according to reviews, in laboratory studies they stimulate the cells that produce the skin's supporting tissue (fibroblasts) | 3% Matrixyl™ 3000 in Firm Baby Firm, for the look of firmness |
| Neurotransmitter-affecting peptides | Target the signal sent from nerve to muscle | 4% Argireline™ in Firm Baby Firm |
| Carrier peptides | Used to carry another molecule | No dedicated product |
| Enzyme-inhibiting peptides | Target the activity of certain enzymes in the skin | No dedicated product |
We have not included the copper tripeptide-1 in Love In Blue This Time in the table: the source abstracts we rely on do not state which group it belongs to. We cover it separately in our article what is copper peptide.
How do Argireline and Matrixyl 3000 work?
Argireline™ targets the signal sent from nerve to muscle; Matrixyl™ 3000 is a peptide raw material aimed at the look of firmness. Argireline is the trade name of a synthetic peptide made up of six amino acids (INCI: Acetyl Hexapeptide-8). In the 2002 study that introduced it, laboratory analyses showed that the peptide interferes with the formation or stability of a protein complex (the SNARE complex) needed to release the substances that carry signals from nerve endings.
Among the sources we rely on, there is no independent study specific to Matrixyl™ 3000, so we do not describe how it works beyond the general framework given for signal peptides.
Do peptides really work?
There are positive findings for some peptides; however, the evidence varies by peptide, and the main limit is skin penetration. The review by Pai and colleagues sums up the picture from two angles:
- Strengths: they are involved in many skin functions, act selectively on their target and have a low tendency to trigger an immune response.
- Weaknesses: evidence from human studies is often weak, and absorption can be limited because of low lipid solubility, high molecular weight and binding to other ingredients.
Argireline is a clear example of this limit. According to a 2025 review, its water-loving structure and relatively large molecule limit its passage through the skin's oily outer layer, and it is unclear whether it reaches the point where nerve and muscle meet. The same review reports positive findings on the look of wrinkles, elasticity and hydration, but the mechanism is not fully understood: the mechanism shown in the laboratory and the result of a cream applied to the skin are separate questions. Reviews also note that penetration can be increased through the type of emulsion, auxiliary ingredients that make penetration easier, chemical modification or encapsulation.
What does “peptide” on a label tell you, and what doesn't it?
The word “peptide” only tells you that the formula contains a peptide; it does not tell you which peptide it is, which group it belongs to or its concentration. The ingredient list shows INCI names, not trade names: the Firm Baby Firm list includes Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7 and Tripeptide-2 alongside Acetyl Hexapeptide-8, and the Love In Blue This Time list includes Copper Tripeptide-1. Concentrations are not shown in the ingredient list; you learn them from the brand's own statement: Firm Baby Firm Firming Peptide Cream contains its peptides as key actives with stated concentrations, whereas in Love In Blue This Time Ceramide and Copper Peptide Serum, copper tripeptide-1 is a supporting ingredient with no stated concentration, and the key actives are 2% ceramide complex and 2% Ethyl Ascorbic Acid. The cream's place in the routine, how often to use it and the eye-area rule are in the guide how to use a peptide cream.
Do peptides have side effects, and who should take care?
There is no common list of side effects for peptides; safety data vary by peptide. The 2002 study that introduced Argireline reports that no primary irritation was seen at high doses; this is the finding of a single study, not an assurance about a cream as a whole. Our sources contain no safety data for Matrixyl 3000.
- Before first use, do a patch test on the inner forearm. If redness, itching or burning occurs, do not use the product, and if the reaction does not go away, see your doctor.
- Do not apply to irritated skin.
- Avoid getting Firm Baby Firm in your eyes.
- Our sources contain no peptide safety data specific to pregnancy and breastfeeding. If you are pregnant or breastfeeding, or have a skin condition, consult your doctor before use.
Frequently asked questions
Are peptides obtained from animal sources?
It depends on the peptide. According to the review by Skibska and Perlikowska, most cosmetic peptides are obtained by chemical synthesis or by the partial breakdown of animal proteins. Argireline is a synthetically designed peptide. The s'hevec range is 100% vegan; the peptides in Firm Baby Firm and Love In Blue This Time are not of animal origin either.
Can a peptide cream correct deep wrinkles?
No. Firm Baby Firm does not smooth away deep wrinkles that remain visible at rest, and it does not correct volume loss or sagging.
At what age should you start using a peptide cream?
There is no set age to start; the decision depends more on your needs than on your age. We also cover the question of when to start in our care routine for the look of fine lines.
Which skin type is a peptide cream suitable for?
Suitability is determined not by the peptide alone but by the cream's full formula. Firm Baby Firm is formulated for dry and normal skin; alongside its peptides, it contains baobab extract, 8D hyaluronic acid and panthenol as supporting ingredients. You will find it among our products for the look of fine lines, together with the barrier serum and the eye serum.
Retinol or peptides?
This does not have to be a choice: the two are different ingredients, and our source list includes no study showing that peptides do the same job as retinol, so we do not say that one replaces the other. The s'hevec range does not include retinol; the peptide step is Firm Baby Firm. How retinol is used and which ingredients it should not share an evening with are covered in the retinol guide.
Can peptides and niacinamide be used together?
Yes. Love In Blue This Time contains copper tripeptide-1 and niacinamide in the same formula. If you use a serum containing niacinamide, the order is the same: serum first, then, once it has absorbed, Firm Baby Firm as the last layer that finishes the routine.
Sources
- Pai VV et al. Topical peptides as cosmeceuticals. Indian J Dermatol Venereol Leprol. 2017.
- Skibska A et al. Signal Peptides - Promising Ingredients in Cosmetics. Curr Protein Pept Sci. 2021.
- Zdrada-Nowak J et al. Acetyl Hexapeptide-8 in Cosmeceuticals-A Review of Skin Permeability and Efficacy. Int J Mol Sci. 2025.
- Blanes-Mira C et al. A synthetic hexapeptide (Argireline) with antiwrinkle activity. Int J Cosmet Sci. 2002.
This content is for information only and does not replace medical advice. s'hevec products are cosmetic products and are not intended for medical treatment. It was prepared by the s'hevec Team on the basis of the s'hevec product data library and the sources listed above.
