Ingredient review
PEG-2 Stearamide Carboxylic Acid
INCI: PEG-2 Stearamide Carboxylic Acid
A gentle, PEG-modified surfactant that helps create a rich foam while being less stripping than traditional sulfates.
In plain English
PEG-2 Stearamide Carboxylic Acid is a mild cleansing ingredient that helps water and oil mix so dirt and makeup can be rinsed away. It produces a creamy foam and is often used in products labeled as gentle or sulfate-free. The 'PEG' part means it has been processed to be water-friendly and less irritating to the skin.
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
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
PEG-2 Stearamide Carboxylic Acid 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-2 Stearamide Carboxylic Acid.
- 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 semi-synthetic surfactant derived from stearic acid (a fatty acid found in vegetable oils) and modified with polyethylene glycol (PEG) to improve its water solubility and mildness.
How it works
It works by reducing the surface tension between water and oil, allowing oils and dirt to be lifted from the skin and rinsed away. Its carboxylic acid group gives it a gentle, pH-responsive cleansing action that is less aggressive than many traditional surfactants.
Pros
Gentle on skin
This surfactant is much milder than sodium lauryl sulfate, making it a good choice for daily cleansing without stripping natural oils.
Creamy foam texture
It produces a rich, luxurious lather that feels pleasant on the skin, which can improve the user experience of sulfate-free cleansers.
Cons and cautions
Potential processing impurities
As a PEG compound, there is a small risk of contamination with 1,4-dioxane during manufacturing, though reputable suppliers purify their ingredients to safe levels.
Not fully natural
It is semi-synthetic, so it may not appeal to those seeking 100% natural or organic skincare products.
Best for
- People with normal to dry skin looking for a gentle cleanser
- Anyone who prefers sulfate-free or low-foam cleansing products
Use caution if
- Those with known allergies to PEG derivatives (rare)
- People who prefer completely natural or plant-only ingredient lists
Usage tips
Safety summary
PEG-2 Stearamide Carboxylic Acid is considered safe for use in cosmetics at typical concentrations. The main safety concern is potential contamination with 1,4-dioxane during manufacturing, but reputable brands ensure purification to meet safety standards. It is non-irritating and non-comedogenic for most skin types.
Research notes
Research on PEG-modified surfactants supports their mildness and low irritation potential compared to traditional anionic surfactants. Regulatory bodies like the Cosmetic Ingredient Review (CIR) have evaluated PEG compounds and found them safe for cosmetic use when properly formulated.
Common label clues
- Typical concentration
- 1–10% in rinse-off products
- Regulatory status
- Approved for use in cosmetics in the US (FDA), EU (CosIng), and other major markets. PEG compounds are generally recognized as safe when properly purified.
- Common uses
- Facial cleansers, Body washes, Shampoos, Foaming gels
- Environmental note
- PEG-based surfactants are generally biodegradable, but their production involves petrochemical processing. Some consumers prefer plant-derived alternatives for environmental reasons.
Good to know
- PEG-2 Stearamide Carboxylic Acid is often used in 'sulfate-free' shampoos to provide gentle cleansing.
- It is compatible with a wide pH range, making it versatile in formulation.
Common questions
What is PEG-2 Stearamide Carboxylic Acid in beauty products?
PEG-2 Stearamide Carboxylic Acid is a mild cleansing ingredient that helps water and oil mix so dirt and makeup can be rinsed away. It produces a creamy foam and is often used in products labeled as gentle or sulfate-free. The 'PEG' part means it has been processed to be water-friendly and less irritating to the skin.
What does PEG-2 Stearamide Carboxylic Acid do in a beauty product?
It works by reducing the surface tension between water and oil, allowing oils and dirt to be lifted from the skin and rinsed away. Its carboxylic acid group gives it a gentle, pH-responsive cleansing action that is less aggressive than many traditional surfactants.
Is PEG-2 Stearamide Carboxylic Acid safe for most people?
PEG-2 Stearamide Carboxylic Acid is considered safe for use in cosmetics at typical concentrations. The main safety concern is potential contamination with 1,4-dioxane during manufacturing, but reputable brands ensure purification to meet safety standards. It is non-irritating and non-comedogenic for most skin types.
Who should be careful with PEG-2 Stearamide Carboxylic Acid?
Those with known allergies to PEG derivatives (rare) People who prefer completely natural or plant-only ingredient lists
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.