Ingredient review
SH-Polypeptide-39
INCI: SH-Polypeptide-39
A lab-made peptide that signals skin to produce more collagen, potentially reducing fine lines over time.
In plain English
SH-Polypeptide-39 is a short chain of amino acids (the building blocks of protein) made in a lab. When applied to skin, it acts like a messenger, telling skin cells to make more collagen and elastin. This can help plump up the skin and soften the appearance of wrinkles. Because it's synthetic, it's very stable and unlikely to cause irritation.
Review score
Safety, usefulness, and evidence
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
Quick decision guide
Useful, but context matters
SH-Polypeptide-39 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-39.
- 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
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
emergingThe ingredient may be promising, but claims should be treated more cautiously.
What it is
SH-Polypeptide-39 is a synthetic peptide, meaning it's a man-made chain of amino acids designed to mimic natural signaling molecules in the skin.
How it works
It works by binding to receptors on skin cells and stimulating them to produce more collagen and other structural proteins. This helps reinforce the skin's support network, leading to firmer, smoother-looking skin over weeks of consistent use.
Pros
Gentle on skin
Unlike some anti-aging ingredients, SH-Polypeptide-39 has a very low irritation risk, making it suitable for sensitive skin types.
Supports collagen naturally
It works by encouraging your skin's own collagen production, which can lead to more natural-looking firmness over time.
Cons and cautions
Slow results
Peptides work gradually. You may need to use a product consistently for several weeks before noticing visible changes in fine lines.
Limited independent research
Most evidence for SH-Polypeptide-39 comes from manufacturer studies. More peer-reviewed research would strengthen confidence in its efficacy.
Best for
- People looking for a gentle anti-aging ingredient
- Those with sensitive skin who cannot tolerate stronger actives like retinol
Use caution if
- Anyone expecting instant results
- Those with known allergies to synthetic peptides (rare)
Usage tips
Safety summary
SH-Polypeptide-39 is considered safe for topical use with a low risk of irritation or allergic reaction. It is not known to be comedogenic (pore-clogging).
Research notes
Evidence for SH-Polypeptide-39 is primarily from manufacturer-sponsored studies showing collagen stimulation in lab models. Human clinical data is limited but promising for mild anti-aging effects.
Common label clues
- Typical concentration
- Typically used at 0.5% to 2% in leave-on products
- Regulatory status
- Generally recognized as safe for cosmetic use in the US and EU when used within recommended concentrations.
- Common uses
- Anti-aging serums, Firming creams, Eye treatments
- Environmental note
- As a synthetic peptide, it is produced in controlled lab conditions, which reduces environmental impact compared to some natural extracts that require harvesting.
Good to know
- Peptides are often listed as 'palmitoyl' something on labels — SH-Polypeptide-39 is a specific sequence.
- It is water-soluble and works best in leave-on formulas like serums, not rinse-off cleansers.
Common questions
What is SH-Polypeptide-39 in beauty products?
SH-Polypeptide-39 is a short chain of amino acids (the building blocks of protein) made in a lab. When applied to skin, it acts like a messenger, telling skin cells to make more collagen and elastin. This can help plump up the skin and soften the appearance of wrinkles. Because it's synthetic, it's very stable and unlikely to cause irritation.
What does SH-Polypeptide-39 do in a beauty product?
It works by binding to receptors on skin cells and stimulating them to produce more collagen and other structural proteins. This helps reinforce the skin's support network, leading to firmer, smoother-looking skin over weeks of consistent use.
Is SH-Polypeptide-39 safe for most people?
SH-Polypeptide-39 is considered safe for topical use with a low risk of irritation or allergic reaction. It is not known to be comedogenic (pore-clogging).
Who should be careful with SH-Polypeptide-39?
Anyone expecting instant results Those with known allergies to synthetic peptides (rare)
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.