Ingredient review
Sodium/TEA-Undecylenoyl Alginate
INCI: SODIUM/TEA-UNDECYLENOYL ALGINATE
A mild, algae-derived cleansing agent that effectively removes dirt and oil while leaving a soft, non-stripped feel on skin.
In plain English
This ingredient is a gentle cleanser made by combining a natural substance from brown algae (alginate) with a fatty acid (undecylenic acid). It helps wash away dirt, oil, and makeup without making your skin feel tight or dry. It also leaves a light, invisible film that can help protect the skin's surface.
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
Sodium/TEA-Undecylenoyl Alginate 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 Sodium/TEA-Undecylenoyl Alginate.
- 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 and film-forming agent created by chemically linking alginate (a polysaccharide from brown seaweed) with undecylenic acid (a fatty acid derived from castor oil). It is designed to be a milder alternative to traditional sulfates.
How it works
In a cleanser, it lowers the surface tension of water, allowing oil and dirt to be lifted away and rinsed off. After rinsing, a small amount remains on the skin, forming a thin, flexible film that helps retain moisture and reduce irritation.
Pros
Very gentle on skin
Unlike harsher sulfates, this ingredient cleans without disrupting the skin's moisture barrier, making it ideal for daily use on sensitive or dry skin.
Helps maintain hydration
The film-forming property leaves a light layer that reduces water loss after washing, so your skin feels softer and less tight.
Cons and cautions
Low foam
It produces minimal lather compared to traditional cleansers, which may feel less satisfying if you associate foam with cleanliness.
Possible residue
On oily or acne-prone skin, the leftover film might feel slightly heavy or contribute to congestion in rare cases.
Best for
- People with dry or sensitive skin looking for a non-stripping cleanser
- Those who prefer sulfate-free, mild cleansing options
Use caution if
- Individuals who prefer high-foam, squeaky-clean cleansers
Usage tips
Safety summary
Sodium/TEA-Undecylenoyl Alginate is considered safe for cosmetic use with a low irritation and comedogenic risk. It is well-tolerated by most skin types, including sensitive skin.
Research notes
Studies on similar alginate derivatives show good skin compatibility and mildness. While direct clinical data on this specific compound is limited, its chemical structure supports a favorable safety profile.
Common label clues
- Typical concentration
- 0.5–5% in rinse-off products
- Regulatory status
- Approved for use in cosmetics in the EU, US, and other major markets. No known restrictions at typical concentrations.
- Common uses
- Cleansers, Facial washes, Shampoos, Body washes
- Environmental note
- Alginate is sourced from sustainably harvested brown seaweed, and undecylenic acid is derived from castor oil, a renewable crop. The ingredient is biodegradable.
Good to know
- This ingredient is often listed near the middle or end of an ingredient list, indicating a moderate concentration.
- It is compatible with other mild surfactants and can be used in sulfate-free formulations.
Common questions
What is Sodium/TEA-Undecylenoyl Alginate in beauty products?
This ingredient is a gentle cleanser made by combining a natural substance from brown algae (alginate) with a fatty acid (undecylenic acid). It helps wash away dirt, oil, and makeup without making your skin feel tight or dry. It also leaves a light, invisible film that can help protect the skin's surface.
What does Sodium/TEA-Undecylenoyl Alginate do in a beauty product?
In a cleanser, it lowers the surface tension of water, allowing oil and dirt to be lifted away and rinsed off. After rinsing, a small amount remains on the skin, forming a thin, flexible film that helps retain moisture and reduce irritation.
Is Sodium/TEA-Undecylenoyl Alginate safe for most people?
Sodium/TEA-Undecylenoyl Alginate is considered safe for cosmetic use with a low irritation and comedogenic risk. It is well-tolerated by most skin types, including sensitive skin.
Who should be careful with Sodium/TEA-Undecylenoyl Alginate?
Individuals who prefer high-foam, squeaky-clean cleansers
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.