Ingredient review

SH-Polypeptide-99

INCI: SH-Polypeptide-99

SH-Polypeptide-99 is a synthetic peptide that may help support skin firmness and reduce fine lines, but research is still emerging.

beautyskincareanti-aging

In plain English

SH-Polypeptide-99 is a lab-made chain of amino acids (the building blocks of protein) designed to signal skin cells to behave more youthfully. Think of it as a tiny messenger that tells your skin to produce more collagen and elastin, which are the proteins that keep skin plump and bouncy. Because it's a synthetic ingredient, it's made in a lab to be very pure and stable in formulas.

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-99 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-99.
  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-99 is a synthetic peptide, meaning it's a short chain of amino acids created in a laboratory. Peptides like this are designed to mimic natural signaling molecules in the skin to encourage repair and renewal.

How it works

In a cosmetic product, SH-Polypeptide-99 is absorbed into the upper layers of the skin where it acts as a signaling molecule. It is believed to stimulate fibroblasts (the cells that make collagen and elastin) to increase production of these structural proteins. Over time, this can help improve skin firmness and reduce the depth of fine lines and wrinkles.

Pros

Gentle anti-aging support

SH-Polypeptide-99 is generally non-irritating and suitable for sensitive skin types, making it a good option for those who cannot tolerate stronger anti-aging ingredients like retinoids.

Targets skin firmness

By signaling collagen production, this peptide may help improve skin firmness and elasticity over consistent use, which is a key concern for aging skin.

Cons and cautions

Limited research

Compared to well-studied peptides like Matrixyl, SH-Polypeptide-99 has fewer published human studies, so its effectiveness is less certain.

Gradual results

Peptides work slowly and require consistent use over weeks to months to see visible improvements. Users looking for quick fixes may be disappointed.

Best for

  • People looking for anti-aging support with minimal irritation
  • Those with sensitive skin who want a gentle alternative to retinoids

Use caution if

  • Anyone with known allergies to synthetic peptides (rare)
  • Those expecting immediate or dramatic results (peptides work gradually)

Usage tips

Apply peptide serums to clean, damp skin to enhance absorption.
Use consistently twice daily for best results, and follow with a moisturizer to lock in the product.
Avoid using with very low pH products (like strong AHAs) at the same time, as peptides can be less stable in acidic environments.

Safety summary

SH-Polypeptide-99 is considered safe for topical use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, making it suitable for most skin types. As with any new ingredient, a patch test is recommended.

Research notes

Research on SH-Polypeptide-99 specifically is limited. General peptide research supports the concept that certain peptides can stimulate collagen production, but direct clinical evidence for this exact peptide is sparse. Most evidence comes from ingredient supplier studies rather than independent peer-reviewed trials.

Common label clues

Typical concentration
Typically used at 0.1% to 1% in leave-on formulations
Regulatory status
SH-Polypeptide-99 is a cosmetic ingredient regulated as a cosmetic product component by the FDA in the US and similar bodies globally. It is not a drug and cannot claim to treat or cure skin conditions.
Common uses
Anti-aging serums, Firming creams, Eye treatments
Environmental note
As a synthetic peptide, its production involves chemical synthesis, which has a moderate environmental footprint compared to plant-derived ingredients. However, it is used in very small amounts per product.

Good to know

  • Peptides are often listed as 'palmitoyl' something or 'acetyl' something on labels—SH-Polypeptide-99 is a less common variant.
  • Store peptide products in a cool, dark place to maintain stability.

Common questions

What is SH-Polypeptide-99 in beauty products?

SH-Polypeptide-99 is a lab-made chain of amino acids (the building blocks of protein) designed to signal skin cells to behave more youthfully. Think of it as a tiny messenger that tells your skin to produce more collagen and elastin, which are the proteins that keep skin plump and bouncy. Because it's a synthetic ingredient, it's made in a lab to be very pure and stable in formulas.

What does SH-Polypeptide-99 do in a beauty product?

In a cosmetic product, SH-Polypeptide-99 is absorbed into the upper layers of the skin where it acts as a signaling molecule. It is believed to stimulate fibroblasts (the cells that make collagen and elastin) to increase production of these structural proteins. Over time, this can help improve skin firmness and reduce the depth of fine lines and wrinkles.

Is SH-Polypeptide-99 safe for most people?

SH-Polypeptide-99 is considered safe for topical use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, making it suitable for most skin types. As with any new ingredient, a patch test is recommended.

Who should be careful with SH-Polypeptide-99?

Anyone with known allergies to synthetic peptides (rare) Those expecting immediate or dramatic results (peptides work gradually)

Research sources

Cosmetic Ingredient Review (CIR) - Safety of PeptidesOpenPubMed - Peptides in CosmeticsOpenFDA - Cosmetics GuidanceOpen

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.