What Is Potassium Stearoyl Glutamate?
Potassium stearoyl glutamate is the potassium salt of stearoyl glutamic acid, a compound that joins a fatty acid called stearic acid with the amino acid glutamic acid. The resulting ingredient looks like a fine, off-white powder that dissolves easily in water and oil blends. Because it carries both water-loving and oil-loving parts, it works as a gentle surfactant and helper that brings formulas together.
The ingredient was first explored in the 1990s when formulators searched for milder, plant-based options to replace harsher detergents. Stearic acid can be sourced from vegetable fats such as coconut or palm while glutamic acid comes from fermented plant sugars. The two are combined, then neutralized with potassium hydroxide to create the final salt. This process is done under controlled heat and pH to keep the compound stable and skin friendly.
You will spot potassium stearoyl glutamate in everyday products like facial cleansers, light moisturizers, sheet masks, creamy body lotions, leave-in hair conditioners and anti-aging serums. Its ability to stabilize emulsions makes textures feel smooth and silky without a heavy or greasy after-feel, so it suits both rinse-off and leave-on formulas.
Potassium Stearoyl Glutamate’s Cosmetic Benefits/Uses
Below are the key ways this ingredient supports skin and hair care formulas.
- Hair conditioning: Helps smooth the hair shaft, improve slip and reduce static so strands feel softer and easier to comb
- Skin conditioning: Forms a light, breathable film that keeps moisture in and leaves skin feeling supple and comfortable without clogging pores
Who Can Use Potassium Stearoyl Glutamate
This ingredient is generally well tolerated by all skin types, including dry, normal, combination and oily skin. Its lightweight finish makes it a good option for acne-prone complexions since it does not leave a heavy, pore-clogging residue. Sensitive skin usually gets on well with it thanks to its mild nature, though anyone with a history of fatty acid or coconut allergies should scan the full ingredient list to be safe.
Potassium stearoyl glutamate is typically sourced from vegetable fats and fermented plant sugars, so products that use plant-based grades are suitable for vegans and vegetarians. If you follow a strict animal-free routine, look for brands that confirm a plant origin or carry a vegan certification.
No research points to problems for women who are pregnant or breastfeeding when this ingredient is applied topically in cosmetic amounts. That said, this information is not medical advice. Expectant and nursing mothers should share any skincare product with their doctor before adding it to a routine, just to stay on the safe side.
The compound does not increase photosensitivity, so it will not make skin more prone to sunburn. Standard sun protection habits remain important, but no extra precautions are needed specifically because of this ingredient.
Potential Side Effects/Adverse Reactions
Reactions to topical potassium stearoyl glutamate vary from person to person. The points below outline potential side effects, although most users will not experience them when the ingredient is properly formulated in a cosmetic product.
- Mild skin irritation such as redness or stinging in very sensitive individuals
- Allergic contact dermatitis in those allergic to coconut, palm or other source materials used to make the fatty acid portion
- Eye irritation if a cleanser or lotion containing the ingredient gets into the eyes
- Temporary scalp sensitivity when used in leave-in hair products on an already compromised scalp
If you notice any discomfort, stop using the product and seek guidance from a qualified healthcare professional.
Comedogenic Rating
Rating: 1 / 5
Potassium stearoyl glutamate sits very low on the comedogenic scale because it is used in small percentages, dissolves well in both water and oil phases and leaves a light non-occlusive film on skin. Unlike pure fatty acids or heavy plant butters it does not build up inside pores, and its amino acid component helps the salt rinse away cleanly. People prone to acne or breakouts can generally use products containing this ingredient without worrying about clogged pores. Formulation matters though, so pairing it with highly comedogenic oils could still pose a risk.
Summary
Potassium stearoyl glutamate mainly acts as a skin and hair conditioner while doubling as a mild surfactant and emulsifier that keeps oil and water beautifully blended. By combining a fatty acid with an amino acid it offers the softening benefits of lipids alongside the water binding talent of proteins, which translates to smoother hair, supple skin and stable creamy textures.
The ingredient is not as mainstream as glycerin or shea butter but its plant origin, gentle profile and multitasking ability have made it increasingly popular in modern clean beauty launches and lightweight K-beauty formulas.
Current data shows it is safe for virtually all skin types with a very low risk of irritation. As with any new cosmetic ingredient it is smart to do a quick patch test when trying a fresh product to make sure your individual skin agrees.