What Is Polyglyceryl-5 Triisostearate?
Polyglyceryl-5 Triisostearate is a plant-derived ingredient made by joining three units of isostearic acid, a fatty acid usually sourced from coconut or rapeseed oil, to a short chain of five glycerin molecules. Chemists first explored this type of “polyglyceryl ester” in the 1990s while looking for gentler alternatives to traditional surfactants, and it soon found a home in skin care because it is mild, biodegradable and works in both water and oil phases.
The production process is straightforward: glycerin is heated to link the molecules into a small “poly” chain, then that chain is reacted with purified isostearic acid in the presence of food-grade catalysts. The result is a glossy, almost wax-like liquid that dissolves in oils yet disperses in water, making it versatile for modern formulations.
You will most often see Polyglyceryl-5 Triisostearate in cleansing balms, oil cleansers, makeup removers, cream foundations, sunscreen lotions, lipsticks and rich moisturizers where it helps marry oil and water while giving a smooth feel on the skin.
Polyglyceryl-5 Triisostearate’s Cosmetic Benefits/Uses
This ingredient pulls double duty in many formulas thanks to the roles below
- Cleansing: Its affinity for both oil and water allows it to lift makeup, sunscreen and daily grime without stripping the skin so products rinse away clean while leaving a soft after-feel
- Emulsifying: It helps keep oil and water mixed, creating stable creams, lotions and balms that do not separate and that glide on smoothly
Who Can Use Polyglyceryl-5 Triisostearate
Because it is gentle and lightweight most skin types can use this ingredient. Dry and mature skin benefit from its silky emollience while combination and oily skin appreciate that it cleanses without leaving a greasy film. Sensitive skin usually tolerates it well as it is free of common irritants. It is generally considered non comedogenic so acne-prone users often find it safe, though individual results can vary.
Polyglyceryl-5 Triisostearate is made from plant sources and contains no animal by-products, so it is suitable for vegans and vegetarians.
Current data show no specific risks for women who are pregnant or breastfeeding when the ingredient is applied topically in cosmetic amounts. This is not medical advice and anyone who is pregnant or nursing should run new products past a qualified health professional just to be safe.
The ingredient does not make skin more sensitive to sunlight and has no known interactions with common actives like retinoids or acids. It is also free of added fragrance and essential oils, making it a good option for those avoiding scent.
Potential Side Effects/Adverse Reactions
Side effects can vary from person to person. The points below list potential reactions only and most users will not experience them when the ingredient is used in a well-formulated product.
- Mild redness or irritation in very sensitive skin
- Temporary stinging if applied to broken or freshly exfoliated skin
- Rare allergic contact dermatitis for individuals with a specific sensitivity to fatty esters
- Occasional clogged pores for those extremely prone to acne
- Eye irritation if the product accidentally gets into the eyes
If any discomfort, persistent redness or swelling occurs stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1 out of 5. Polyglyceryl-5 Triisostearate has a low molecular weight yet it is highly branched and disperses well in water, factors that help it rinse away without lingering in pores. Unlike heavy straight-chain oils it does not form a dense occlusive film, so it is unlikely to trap dead skin cells or bacteria.
Most people who are prone to acne or breakouts can use products containing this ingredient without issue, although individual reactions can still differ.
Formulas that pair it with heavier plant butters or waxes may alter the overall pore-clogging potential so always look at the full ingredient list, not just one component.
Summary
Polyglyceryl-5 Triisostearate acts mainly as a gentle cleanser and an emulsifier. Its dual affinity for oil and water lets it grab onto sebum, makeup and sunscreen then rinse clean while also binding oil and water together so creams, balms and foundations stay silky and stable.
The ingredient is quietly popular in modern balm cleansers, stick foundations and hybrid sunscreens, particularly in Korean and Japanese formulas, though it has yet to reach the household-name status of classic surfactants.
Current research and decades of cosmetic use show it is safe for topical application with a very low risk of irritation or sensitization. As with any new skincare ingredient it is smart to perform a quick patch test when trying a product for the first time just to make sure your skin agrees with it.