Ingredient review

SH-Polypeptide-25

INCI: SH-Polypeptide-25

A synthetic peptide that may help reduce fine lines by signaling skin to produce more collagen, but results vary and long-term data is still emerging.

beautyskincareanti-aging

In plain English

SH-Polypeptide-25 is a lab-made protein fragment that tells your skin cells to make more collagen. Collagen is the scaffolding that keeps skin plump and firm. As we age, collagen production slows down, leading to wrinkles. This peptide is like a messenger that encourages your skin to rebuild that support structure. It's often found in anti-aging serums and creams, but it's not a quick fix—consistent use over weeks to months is needed to see subtle improvements.

Review score

Safety, usefulness, and evidence

4.0Good

4.0/ 5

Potentially useful with some tradeoffs

The evidence base is useful, but some claims depend heavily on the formula.

Risk flags are low for most users, though the finished product can still irritate.

Source: synthetic
Evidence: moderate
Irritation: low
Clogging risk: low

How reviews are scored

Quick decision guide

Useful, but context matters

SH-Polypeptide-25 is generally a lower-concern ingredient when the full formula suits your skin.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

Step 1Start with the score, then check the irritation and clogging risk before judging SH-Polypeptide-25.
Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

SH-Polypeptide-25 is a synthetic peptide, meaning it's a short chain of amino acids made in a lab. It belongs to a class of ingredients called signal peptides, which are designed to mimic natural peptides that trigger collagen synthesis in the skin.

How it works

When applied topically, SH-Polypeptide-25 penetrates the outer layer of skin and binds to receptors on fibroblasts (the cells that produce collagen). This binding sends a signal to ramp up collagen production, which can help improve skin firmness and reduce the appearance of fine lines over time.

Pros

Gentle anti-aging

SH-Polypeptide-25 is non-irritating for most skin types, making it a good option for sensitive skin or those new to anti-aging ingredients.

Targets collagen production

Unlike surface-level moisturizers, this peptide works at a cellular level to support the skin's structure, potentially improving firmness over time.

Cons and cautions

Slow results

You won't see changes overnight. It typically takes 8–12 weeks of consistent use to notice any difference in fine lines, and the effect is modest.

Limited evidence

While signal peptides in general have some research backing, specific studies on SH-Polypeptide-25 are scarce, so the evidence is mostly based on the class rather than this exact ingredient.

Best for

Adults looking for gentle anti-aging support
Those with sensitive skin who cannot tolerate stronger actives like retinol

Use caution if

Anyone allergic to synthetic peptides (rare)
Those expecting immediate or dramatic wrinkle reversal

Usage tips

Apply after cleansing and before heavier creams to allow better absorption.

Use consistently twice daily for at least 8 weeks to evaluate effectiveness.

Pair with a moisturizer containing ceramides or hyaluronic acid to support skin barrier function.

Safety summary

SH-Polypeptide-25 has a low irritation and comedogenic risk, making it suitable for most skin types. No significant safety concerns have been reported in cosmetic use, but individual sensitivity is always possible.

Research notes

Signal peptides like SH-Polypeptide-25 are supported by in vitro and some clinical studies showing they can stimulate collagen production. However, specific peer-reviewed human trials for this exact peptide are limited, so the evidence is considered moderate.

Common label clues

Typical concentration: Typically used at 0.5% to 5% in leave-on products
Regulatory status: In the US, SH-Polypeptide-25 is regulated as a cosmetic ingredient and is not subject to FDA pre-market approval. It is generally considered safe for topical use when formulated properly.
Common uses: Anti-aging serums, Eye creams, Firming moisturizers
Environmental note: As a synthetic peptide, it is produced in a lab, which reduces the need for animal-derived or plant-based raw materials. However, the manufacturing process may involve chemical solvents and energy use.

Good to know

Peptides are fragile—avoid using them with very low pH products (like strong AHAs) at the same time, as acidity can break them down.
SH-Polypeptide-25 is often listed near the middle or end of an ingredient list, as it's effective at low concentrations.

Common questions

What is SH-Polypeptide-25 in beauty products?

What does SH-Polypeptide-25 do in a beauty product?

Is SH-Polypeptide-25 safe for most people?

Who should be careful with SH-Polypeptide-25?

Anyone allergic to synthetic peptides (rare) Those expecting immediate or dramatic wrinkle reversal

Research sources

PubMed - Signal peptides in cosmeticsOpen Cosmetic Ingredient Review - Safety of peptidesOpen FDA - Cosmetics overviewOpen

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.