Ingredient review
PEG-150 Stearate
INCI: PEG-150 Stearate
A gentle, widely used emulsifier that stabilizes formulas and gives a smooth feel, with a strong safety record in cosmetics.
In plain English
PEG-150 Stearate is a synthetic ingredient made from stearic acid (a fatty acid found in plants and animals) and polyethylene glycol (PEG). It acts like a bridge between oil and water, allowing them to mix into a stable cream or lotion. It also thickens the product slightly, making it feel richer and more luxurious on the skin. PEG-150 Stearate is considered very safe and non-irritating at the low levels used in cosmetics.
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-150 Stearate 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-150 Stearate.
- 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
PEG-150 Stearate is a polyethylene glycol derivative of stearic acid. It belongs to a class of ingredients called emulsifiers, which are essential for creating smooth, uniform mixtures of oil and water in skincare and haircare products.
How it works
In a cosmetic formula, PEG-150 Stearate positions itself at the boundary between oil and water droplets. Its water-loving (hydrophilic) PEG chain extends into the water phase, while its oil-loving (lipophilic) stearate tail embeds in the oil phase. This reduces surface tension and prevents the two phases from separating, creating a stable emulsion. It also increases the viscosity of the water phase, giving the product a thicker, more spreadable consistency.
Pros
Gentle and non-irritating
PEG-150 Stearate has a very low irritation and sensitization profile, making it suitable for sensitive skin and daily-use products.
Improves product stability
It prevents oil and water from separating, so your lotion or cream stays consistent and effective from first use to last.
Cons and cautions
Synthetic origin
As a PEG compound, it is manufactured through chemical processes, which may be a drawback for consumers seeking natural or minimal-ingredient formulations.
Potential tackiness at high levels
In formulas with very high concentrations, it can leave a slightly sticky or heavy feel on the skin, though this is rare in well-balanced products.
Best for
- Anyone using creams, lotions, or cleansers who wants a stable, smooth formula
- People with normal to dry skin who appreciate a richer texture
Use caution if
- Those strictly avoiding all synthetic or PEG-based ingredients
Usage tips
Safety summary
PEG-150 Stearate is considered safe for use in cosmetics at typical concentrations. It has low acute toxicity, is not a skin sensitizer, and is not known to be carcinogenic or mutagenic. The CIR panel has reviewed it and found no significant safety concerns.
Research notes
Safety assessments by the Cosmetic Ingredient Review (CIR) and European Chemicals Agency (ECHA) support its safe use. No recent peer-reviewed studies highlight specific risks at cosmetic levels. Its function as an emulsifier is well-documented in formulation science.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US (FDA) and EU (CosIng). The Cosmetic Ingredient Review (CIR) panel has deemed it safe as used.
- Common uses
- Creams, Lotions, Cleansers, Conditioners
- Environmental note
- PEG compounds are generally biodegradable, but their production involves ethylene oxide, which is derived from fossil fuels. Some PEGs may contain trace impurities like 1,4-dioxane, though levels are tightly regulated and typically below harmful thresholds.
Good to know
- PEG-150 Stearate is approved by the FDA for use in cosmetics and is listed in the EU CosIng database.
- The '150' refers to the average number of ethylene oxide units in the PEG chain, which influences its water solubility and thickening ability.
Common questions
What is PEG-150 Stearate in beauty products?
PEG-150 Stearate is a synthetic ingredient made from stearic acid (a fatty acid found in plants and animals) and polyethylene glycol (PEG). It acts like a bridge between oil and water, allowing them to mix into a stable cream or lotion. It also thickens the product slightly, making it feel richer and more luxurious on the skin. PEG-150 Stearate is considered very safe and non-irritating at the low levels used in cosmetics.
What does PEG-150 Stearate do in a beauty product?
In a cosmetic formula, PEG-150 Stearate positions itself at the boundary between oil and water droplets. Its water-loving (hydrophilic) PEG chain extends into the water phase, while its oil-loving (lipophilic) stearate tail embeds in the oil phase. This reduces surface tension and prevents the two phases from separating, creating a stable emulsion. It also increases the viscosity of the water phase, giving the product a thicker, more spreadable consistency.
Is PEG-150 Stearate safe for most people?
PEG-150 Stearate is considered safe for use in cosmetics at typical concentrations. It has low acute toxicity, is not a skin sensitizer, and is not known to be carcinogenic or mutagenic. The CIR panel has reviewed it and found no significant safety concerns.
Who should be careful with PEG-150 Stearate?
Those strictly avoiding all synthetic or PEG-based ingredients
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.