Ingredient review

SH-Polypeptide-56 / RH-Polypeptide-65

INCI: SH-Polypeptide-56, RH-Polypeptide-65

A synthetic peptide duo that may help signal skin to look firmer and smoother, but research is still early and results vary.

beautyskincareanti-aging

In plain English

These are man-made chains of amino acids (peptides) that act like tiny messengers for your skin. They're added to products to encourage skin cells to behave as if they're younger—potentially boosting collagen and reducing the look of wrinkles. Think of them as a gentle nudge to your skin's natural repair system, not a magic eraser.

Review score

Safety, usefulness, and evidence

3.8Good
3.8/ 5

Potentially useful with some tradeoffs

The evidence base is still emerging, so marketing claims deserve extra caution.

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

Source
synthetic
Evidence
emerging
Irritation
low
Clogging risk
low
How reviews are scored

Quick decision guide

Useful, but context matters

SH-Polypeptide-56 / RH-Polypeptide-65 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.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging SH-Polypeptide-56 / RH-Polypeptide-65.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. 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

emerging

The ingredient may be promising, but claims should be treated more cautiously.

What it is

SH-Polypeptide-56 and RH-Polypeptide-65 are synthetic peptides, meaning they are short chains of amino acids created in a lab. They belong to a class of ingredients called signal peptides, which are designed to mimic natural peptide fragments that trigger skin repair processes.

How it works

When applied topically, these peptides are thought to bind to receptors on skin cells and send signals that encourage the production of collagen and other structural proteins. Over time, this may help improve skin firmness and reduce the depth of fine lines. However, because peptides are large molecules, their ability to penetrate deeply into the skin is limited, and their effects are generally mild and gradual.

Pros

Gentle signaling

Unlike stronger actives like retinoids, these peptides rarely cause irritation, making them suitable for sensitive skin or as a daily maintenance ingredient.

Compatible with other actives

They can be layered with vitamin C, niacinamide, or hyaluronic acid without causing negative reactions, so they fit easily into most routines.

Cons and cautions

Subtle effects

Don't expect overnight changes. These peptides work slowly, and visible improvements in firmness or lines may take several months of consistent use.

Limited specific data

Most peptide research is on related sequences, not SH-Polypeptide-56 or RH-Polypeptide-65 specifically, so the evidence for these exact ingredients is still emerging.

Best for

  • Anyone looking for a gentle, non-irritating anti-aging ingredient
  • People with early signs of aging who want a supportive addition to their routine

Use caution if

  • Those expecting dramatic, fast results—peptides work slowly and subtly

Usage tips

Apply after cleansing and before heavier creams to allow better absorption.
Use consistently twice daily for at least 8–12 weeks to see potential benefits.
Store products containing peptides in a cool, dark place to help maintain stability.

Safety summary

SH-Polypeptide-56 and RH-Polypeptide-65 are considered safe for topical cosmetic use at typical concentrations. They have low irritation and allergy potential, though any new ingredient should be patch-tested if you have very sensitive skin.

Research notes

While signal peptides as a class have some clinical support for anti-aging benefits, specific published studies on SH-Polypeptide-56 and RH-Polypeptide-65 are scarce. Most evidence comes from manufacturer data and broader peptide research. More independent studies are needed to confirm their efficacy.

Common label clues

Typical concentration
0.1% to 1% of the formula
Regulatory status
Generally recognized as safe for cosmetic use in the EU, US, and other major markets. Not classified as a drug ingredient.
Common uses
Anti-aging serums, Eye creams, Firming lotions
Environmental note
Synthetic peptides are produced through chemical synthesis, which has a lower environmental footprint than harvesting from animal or plant sources.

Good to know

  • Peptides are fragile—avoid formulas with very low pH (below 4) or high concentrations of alcohol, which can break them down.
  • These peptides are often listed near the end of an ingredient list, meaning they are present in low concentrations, which is typical for active peptides.

Common questions

What is SH-Polypeptide-56 / RH-Polypeptide-65 in beauty products?

These are man-made chains of amino acids (peptides) that act like tiny messengers for your skin. They're added to products to encourage skin cells to behave as if they're younger—potentially boosting collagen and reducing the look of wrinkles. Think of them as a gentle nudge to your skin's natural repair system, not a magic eraser.

What does SH-Polypeptide-56 / RH-Polypeptide-65 do in a beauty product?

When applied topically, these peptides are thought to bind to receptors on skin cells and send signals that encourage the production of collagen and other structural proteins. Over time, this may help improve skin firmness and reduce the depth of fine lines. However, because peptides are large molecules, their ability to penetrate deeply into the skin is limited, and their effects are generally mild and gradual.

Is SH-Polypeptide-56 / RH-Polypeptide-65 safe for most people?

SH-Polypeptide-56 and RH-Polypeptide-65 are considered safe for topical cosmetic use at typical concentrations. They have low irritation and allergy potential, though any new ingredient should be patch-tested if you have very sensitive skin.

Who should be careful with SH-Polypeptide-56 / RH-Polypeptide-65?

Those expecting dramatic, fast results—peptides work slowly and subtly

Research sources

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.