Ingredient review
Stearamidoethyl Diethanolamine
INCI: STEARAMIDOETHYL DIETHANOLAMINE
A synthetic foam booster that can improve lather and thickness but may be drying or irritating for sensitive skin.
In plain English
Stearamidoethyl diethanolamine is a man-made ingredient added to cleansers and shampoos to make them foam more richly and feel thicker. It helps create a creamy, luxurious lather, but because it is a type of amine-based surfactant, it can strip natural oils and cause dryness or irritation for some people, especially those with sensitive or dry 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.
Main practical flags: irritation is moderate; clogging risk is moderate.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- moderate
- Clogging risk
- moderate
Quick decision guide
Useful, but context matters
Stearamidoethyl Diethanolamine can be useful, but watch for some irritation potential and possible clogging concerns.
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 Stearamidoethyl Diethanolamine.
- 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
moderateCan bother some users, especially with frequent use, damaged skin, or strong companion ingredients.
Clogging risk
moderateMay be fine for many users but deserves caution if you are breakout-prone.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A synthetic fatty acid amide derived from stearic acid (a saturated fat) and diethanolamine (DEA). It functions as a surfactant and foam booster in rinse-off products.
How it works
It lowers the surface tension between water and oil, helping to lift dirt and oil from the skin or hair. It also increases the viscosity (thickness) of the product and stabilizes foam, giving a richer lather.
Pros
Rich foam
Creates a dense, creamy lather that many people find satisfying in shampoos and body washes.
Thickens formulas
Helps achieve a luxurious, gel-like consistency without needing additional thickeners.
Cons and cautions
Can be drying
May strip natural oils from the skin and hair, leading to tightness or dryness after washing.
Potential irritant
Some individuals, especially those with sensitive skin, may experience redness or stinging with regular use.
Best for
- People with normal to oily skin who enjoy a rich lather
- Those using rinse-off products and not prone to irritation
Use caution if
- Individuals with dry, sensitive, or eczema-prone skin
- Anyone looking to minimize synthetic surfactants in their routine
Usage tips
Safety summary
Generally safe for most people in rinse-off products at low concentrations, but can cause dryness or irritation in sensitive individuals. Avoid if you have a known sensitivity to DEA derivatives.
Research notes
Limited direct studies on this specific ingredient, but the broader DEA surfactant class has been evaluated by the CIR and EU SCCS, concluding safety in rinse-off products at low levels. No strong evidence of significant health risks when used as intended.
Common label clues
- Typical concentration
- 0.5% to 3% of the formula
- Regulatory status
- Approved for use in cosmetics in the US and EU, with concentration limits in some regions. The CIR has reviewed it and found it safe in rinse-off products at up to 5%.
- Common uses
- Shampoos, Body washes, Facial cleansers, Liquid soaps
- Environmental note
- As a synthetic surfactant, it may have moderate persistence in water systems; however, it is generally biodegradable under standard wastewater treatment conditions.
Good to know
- This ingredient is a DEA derivative; regulatory bodies like the Cosmetic Ingredient Review (CIR) have deemed it safe in rinse-off products at typical concentrations.
- It is not commonly found in 'clean' or natural beauty lines due to its synthetic origin and potential for irritation.
Common questions
What is Stearamidoethyl Diethanolamine in beauty products?
Stearamidoethyl diethanolamine is a man-made ingredient added to cleansers and shampoos to make them foam more richly and feel thicker. It helps create a creamy, luxurious lather, but because it is a type of amine-based surfactant, it can strip natural oils and cause dryness or irritation for some people, especially those with sensitive or dry skin.
What does Stearamidoethyl Diethanolamine do in a beauty product?
It lowers the surface tension between water and oil, helping to lift dirt and oil from the skin or hair. It also increases the viscosity (thickness) of the product and stabilizes foam, giving a richer lather.
Is Stearamidoethyl Diethanolamine safe for most people?
Generally safe for most people in rinse-off products at low concentrations, but can cause dryness or irritation in sensitive individuals. Avoid if you have a known sensitivity to DEA derivatives.
Who should be careful with Stearamidoethyl Diethanolamine?
Individuals with dry, sensitive, or eczema-prone skin Anyone looking to minimize synthetic surfactants in their routine
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.