Ingredient review
PEI-1000
INCI: PEI-1000
PEI-1000 is a synthetic polymer that helps create a smooth, even film on skin, but it's not a star ingredient and is best understood as a texture enhancer.
In plain English
PEI-1000 is a man-made ingredient that helps other ingredients spread evenly on your skin and can make products feel smoother. Think of it like a helper that creates a thin, invisible layer on your skin's surface. It doesn't actively treat skin concerns but improves how a product feels and performs.
Review score
Safety, usefulness, and evidence
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
Quick decision guide
Useful, but context matters
PEI-1000 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 PEI-1000.
- 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
moderateThere is useful support, but formula details and claim strength still matter.
What it is
PEI-1000 is a type of polyethylenimine, a synthetic polymer with a specific molecular weight (around 1000 Daltons). In cosmetics, it's used to modify the texture and feel of products.
How it works
When applied, PEI-1000 forms a thin, flexible film on the skin. This film helps other ingredients stay in place and can give the skin a temporarily smoother appearance. It also helps control the thickness (viscosity) of a product, making it easier to apply.
Pros
Improves texture
PEI-1000 helps create a silky, smooth feel in creams and serums, making them more pleasant to apply.
Enhances spreadability
It helps other ingredients glide across the skin, ensuring even coverage without pilling or clumping.
Cons and cautions
No active skin benefit
PEI-1000 is a functional ingredient that improves product feel but doesn't directly hydrate, brighten, or protect the skin.
Synthetic origin
As a man-made polymer, it may not be preferred by those seeking natural or minimal-ingredient formulations.
Best for
- Anyone looking for a product with a smooth, elegant texture
- Those who want a product that spreads easily and evenly
Use caution if
- Those who strictly avoid synthetic ingredients
- Individuals with known sensitivities to film-forming polymers (rare)
Usage tips
Safety summary
PEI-1000 is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, but as with any ingredient, patch testing is recommended for sensitive individuals.
Research notes
Research on PEI-1000 in cosmetics is limited. Most safety data comes from general polymer studies and industry safety assessments, which indicate low toxicity and skin irritation at cosmetic use levels.
Common label clues
- Typical concentration
- Typically used at 0.1% to 2%
- Regulatory status
- PEI-1000 is not specifically restricted by major cosmetic regulators like the FDA or EU CosIng, but it must meet general safety requirements for cosmetic ingredients.
- Common uses
- Serums, Moisturizers, Sunscreens, Makeup
- Environmental note
- As a synthetic polymer, PEI-1000 may not be biodegradable. Its environmental impact is not well-studied in cosmetic contexts.
Good to know
- PEI-1000 is different from other polyethylenimines used in industrial applications; cosmetic-grade versions are purified and safe for topical use.
- It is not a common ingredient in 'clean beauty' formulations due to its synthetic nature.
Common questions
What is PEI-1000 in beauty products?
PEI-1000 is a man-made ingredient that helps other ingredients spread evenly on your skin and can make products feel smoother. Think of it like a helper that creates a thin, invisible layer on your skin's surface. It doesn't actively treat skin concerns but improves how a product feels and performs.
What does PEI-1000 do in a beauty product?
When applied, PEI-1000 forms a thin, flexible film on the skin. This film helps other ingredients stay in place and can give the skin a temporarily smoother appearance. It also helps control the thickness (viscosity) of a product, making it easier to apply.
Is PEI-1000 safe for most people?
PEI-1000 is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, but as with any ingredient, patch testing is recommended for sensitive individuals.
Who should be careful with PEI-1000?
Those who strictly avoid synthetic ingredients Individuals with known sensitivities to film-forming polymers (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.