Ingredient review
PEG-40 Glyceryl Triisostearate
INCI: PEG-40 Glyceryl Triisostearate
A reliable synthetic emulsifier that helps create stable, creamy formulas, but may not suit those avoiding PEGs.
In plain English
PEG-40 Glyceryl Triisostearate is a man-made ingredient that acts like a bridge between oil and water. In your skincare, it helps keep the formula from separating, so your lotion or cream stays smooth and consistent. It also has mild cleansing properties, which is why you'll find it in some makeup removers and gentle cleansers.
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
PEG-40 Glyceryl Triisostearate 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 PEG-40 Glyceryl Triisostearate.
- 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
A synthetic compound made by reacting polyethylene glycol (PEG) with glyceryl triisostearate, a fat derived from stearic acid. It belongs to a class of ingredients called emulsifiers, which are essential for mixing oil and water phases in cosmetic products.
How it works
It reduces the surface tension between oil and water, allowing them to blend into a stable emulsion. This prevents the product from separating into layers and gives it a smooth, uniform texture. It also helps other ingredients spread evenly on the skin.
Pros
Excellent emulsifier
Creates stable, long-lasting blends of oil and water, so your products stay smooth and don't separate.
Gentle on skin
Low irritation and comedogenic risk, making it suitable for most skin types, including sensitive skin.
Cons and cautions
Synthetic origin
Made from petrochemicals, which may not align with a natural or minimalist skincare philosophy.
Potential processing impurities
PEGs can contain trace amounts of ethylene oxide or 1,4-dioxane if not properly purified, though reputable manufacturers use high-purity grades.
Best for
- People who use lotions, creams, or makeup removers and want a stable, non-greasy texture
- Those with normal to combination skin looking for a gentle emulsifier
Use caution if
- Individuals who strictly avoid PEG-based ingredients due to personal preference or ethical sourcing concerns
Usage tips
Safety summary
PEG-40 Glyceryl Triisostearate is considered safe for use in cosmetics at typical concentrations. The main concern is potential contamination with ethylene oxide during manufacturing, but high-purity grades minimize this risk. It has low irritation and comedogenic potential.
Research notes
The Cosmetic Ingredient Review (CIR) panel has reviewed PEG compounds and concluded they are safe for use in cosmetics. No significant human or animal studies specifically on this ingredient are available, but its safety profile is inferred from the broader PEG family.
Common label clues
- Typical concentration
- 1% to 5%
- Regulatory status
- Approved for use in cosmetics by the FDA and the European Commission. The Cosmetic Ingredient Review (CIR) panel has evaluated PEG compounds and found them safe as used.
- Common uses
- Moisturizers, Cleansers, Makeup removers, Sunscreens
- Environmental note
- As a synthetic compound, it is not biodegradable in the same way as natural ingredients, but it is not known to be bioaccumulative.
Good to know
- PEG-40 Glyceryl Triisostearate is often used in conjunction with other emulsifiers to achieve the desired texture.
- It is considered safe by major regulatory bodies when used in cosmetic concentrations.
Common questions
What is PEG-40 Glyceryl Triisostearate in beauty products?
PEG-40 Glyceryl Triisostearate is a man-made ingredient that acts like a bridge between oil and water. In your skincare, it helps keep the formula from separating, so your lotion or cream stays smooth and consistent. It also has mild cleansing properties, which is why you'll find it in some makeup removers and gentle cleansers.
What does PEG-40 Glyceryl Triisostearate do in a beauty product?
It reduces the surface tension between oil and water, allowing them to blend into a stable emulsion. This prevents the product from separating into layers and gives it a smooth, uniform texture. It also helps other ingredients spread evenly on the skin.
Is PEG-40 Glyceryl Triisostearate safe for most people?
PEG-40 Glyceryl Triisostearate is considered safe for use in cosmetics at typical concentrations. The main concern is potential contamination with ethylene oxide during manufacturing, but high-purity grades minimize this risk. It has low irritation and comedogenic potential.
Who should be careful with PEG-40 Glyceryl Triisostearate?
Individuals who strictly avoid PEG-based ingredients due to personal preference or ethical sourcing concerns
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.