Ingredient review
Potassium Stearoyl Glutamate
INCI: Potassium Stearoyl Glutamate
A mild, amino-acid-based surfactant that cleanses without stripping the skin, making it ideal for sensitive and dry skin types.
In plain English
Potassium Stearoyl Glutamate is a gentle cleansing ingredient made from a fatty acid (stearic acid) and an amino acid (glutamic acid). It works like a soap but is much milder, creating a soft, creamy foam that lifts away dirt and oil without leaving your skin feeling tight or dry. Because it's derived from natural building blocks your skin recognizes, it's less likely to cause irritation than traditional sulfates or soaps.
Review score
Safety, usefulness, and evidence
Strong fit for many routines
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
Easy yes for most routines
Potassium Stearoyl Glutamate 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 Potassium Stearoyl Glutamate.
- 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 emulsifier formed by combining stearic acid (a fatty acid found in many plant and animal fats) with glutamic acid (an amino acid naturally present in the skin). The result is a mild, biodegradable cleansing agent that is often used in sulfate-free and gentle skincare formulations.
How it works
It reduces the surface tension between water and oil, allowing impurities to be rinsed away. Unlike harsher surfactants, it has a larger molecular structure that doesn't penetrate the skin barrier deeply, so it cleanses effectively while preserving the skin's natural moisture and lipid balance. It also helps stabilize emulsions, keeping oil and water blended in creams and lotions.
Pros
Extremely gentle on skin
Its large molecular size means it cleanses without penetrating or disrupting the skin barrier, making it one of the mildest surfactants available.
Supports a healthy moisture balance
Unlike sulfates that can strip natural oils, this ingredient helps maintain the skin's hydration, leaving it soft and comfortable after washing.
Cons and cautions
Lower foam volume
It produces a creamy, low-foam lather rather than big, bubbly suds. Some users accustomed to high-foam cleansers may feel it doesn't clean as thoroughly, even though it does.
Higher cost
Amino-acid-based surfactants are more expensive to produce than traditional sulfates, so products containing them often come with a higher price tag.
Best for
- People with dry or sensitive skin looking for a non-stripping cleanser
- Those who prefer sulfate-free or amino-acid-based cleansing products
Use caution if
- Individuals with a known allergy to stearic acid or glutamic acid (rare)
- Those who prefer high-foaming, bubbly cleansers may find it too mild
Usage tips
Safety summary
Potassium Stearoyl Glutamate is considered very safe for cosmetic use. It has a low irritation and sensitization potential, making it suitable for sensitive skin. No significant safety concerns have been reported in the scientific literature at typical use concentrations.
Research notes
Amino-acid-based surfactants like Potassium Stearoyl Glutamate have been studied for their mildness and skin compatibility. Research indicates they cause less disruption to the skin barrier and less protein denaturation than sodium lauryl sulfate. However, direct clinical studies on this specific ingredient are limited, with most evidence coming from broader surfactant safety evaluations.
Common label clues
- Typical concentration
- 1–15% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics by the FDA (as part of generally recognized safe ingredients) and listed in the EU CosIng database. No known restrictions at typical use levels.
- Common uses
- Facial cleansers, Body washes, Shampoos, Bar soaps, Makeup removers
- Environmental note
- Derived from renewable plant sources (stearic acid from palm or coconut oil) and amino acids. It is biodegradable and has a lower aquatic toxicity compared to many conventional surfactants.
Good to know
- Potassium Stearoyl Glutamate is often found in 'amino acid' cleansers, which are popular in Korean and Japanese skincare routines.
- It is biodegradable and considered more eco-friendly than many petroleum-based surfactants.
Common questions
What is Potassium Stearoyl Glutamate in beauty products?
Potassium Stearoyl Glutamate is a gentle cleansing ingredient made from a fatty acid (stearic acid) and an amino acid (glutamic acid). It works like a soap but is much milder, creating a soft, creamy foam that lifts away dirt and oil without leaving your skin feeling tight or dry. Because it's derived from natural building blocks your skin recognizes, it's less likely to cause irritation than traditional sulfates or soaps.
What does Potassium Stearoyl Glutamate do in a beauty product?
It reduces the surface tension between water and oil, allowing impurities to be rinsed away. Unlike harsher surfactants, it has a larger molecular structure that doesn't penetrate the skin barrier deeply, so it cleanses effectively while preserving the skin's natural moisture and lipid balance. It also helps stabilize emulsions, keeping oil and water blended in creams and lotions.
Is Potassium Stearoyl Glutamate safe for most people?
Potassium Stearoyl Glutamate is considered very safe for cosmetic use. It has a low irritation and sensitization potential, making it suitable for sensitive skin. No significant safety concerns have been reported in the scientific literature at typical use concentrations.
Who should be careful with Potassium Stearoyl Glutamate?
Individuals with a known allergy to stearic acid or glutamic acid (rare) Those who prefer high-foaming, bubbly cleansers may find it too mild
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.