What Is Glycereth-17 Polyhydroxystearate?
Glycereth-17 Polyhydroxystearate is a specialty ester created by joining a 17-mole ethoxylated form of glycerin with polyhydroxystearic acid. The glycerin used often comes from plant oils like soybean or palm, while the fatty acid part is usually derived from castor or similar sources. Chemists first explored this molecule in the late twentieth century when the cosmetics industry began looking for gentler yet more reliable ways to keep oil and water blends from separating. Production involves ethoxylating glycerin to add 17 units of ethylene oxide, then reacting that intermediate with polyhydroxystearic acid under controlled heat and vacuum until a smooth amber-colored liquid forms.
Thanks to its outstanding ability to hold emulsions together, manufacturers add Glycereth-17 Polyhydroxystearate to many water-in-oil and oil-in-water products. You will often spot it in sunscreens, tinted moisturizers, liquid foundations, cleansing balms, rich night creams, sheet masks and anti aging serums where a silky feel and long-term stability are must-haves.
Glycereth-17 Polyhydroxystearate’s Cosmetic Benefits/Uses
This ingredient serves one main purpose in skincare and makeup, yet that single role brings several practical rewards for both the formulator and the user.
As an emulsion stabilizer, Glycereth-17 Polyhydroxystearate locks together the oil and water phases so the formula stays uniform from the factory line to your bathroom shelf. A stable emulsion keeps active ingredients evenly distributed, delivers a smooth non-greasy texture, prevents unsightly separation rings and extends the product’s life span. The result is a lotion, cream or balm that feels better during application and works the same way every time you use it.
Who Can Use Glycereth-17 Polyhydroxystearate
This emulsifier is considered gentle enough for most skin types including dry, oily, combination and sensitive skin because it stays on the surface and does not change how your skin naturally works. People with very reactive or allergy-prone skin can still use it but should look at the whole ingredient list to make sure nothing else inside the product is a trigger.
The raw materials are typically plant sourced so finished products that rely on Glycereth-17 Polyhydroxystearate are usually suitable for vegans and vegetarians. Brands may still add animal-derived ingredients elsewhere in the formula so it is smart to check the full label if that is a concern.
No data link this ingredient to problems during pregnancy or while breastfeeding when used on the skin. Even so this is not medical advice and anyone who is pregnant or nursing should run any skincare choice past a trusted doctor to be safe.
Glycereth-17 Polyhydroxystearate is not known to cause photosensitivity, meaning it will not make skin more likely to burn in sunlight. Standard daytime protection such as sunscreen is still important because other actives in the product or in your routine may need it.
Potential Side Effects/Adverse Reactions
Responses to topical Glycereth-17 Polyhydroxystearate vary from person to person. The points below cover potential issues yet most users will not notice any of them when the product is well made and used as directed.
- Mild redness or stinging in very sensitive skin
- Rare allergic contact dermatitis if you are sensitive to polyethylene glycol type compounds
- Transient eye irritation if the formula accidentally gets into the eyes
- Clogged pores in a small number of users who are extremely acne prone
If you experience any of these reactions stop using the product and seek advice from a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 1 / 5
Glycereth-17 Polyhydroxystearate earns a low score because its bulky, water-friendly structure sits on the surface and rinses away without sinking deep into pores. It does not act like heavy plant oils or waxes that can trap dead cells and sebum. While a handful of very acne-prone users may still notice congestion, most people will not see breakouts directly linked to this molecule.
In formulas packed with rich butters or occlusive silicones the overall product could feel heavier, so the final texture matters more than this single ingredient.
Suitable for acne-prone skin: Yes, in most cases.
Summary
Glycereth-17 Polyhydroxystearate is mainly an emulsion stabilizer. Its glycerin end loves water while its fatty acid end loves oil, so it anchors itself at the boundary of the two phases and keeps creams, lotions and makeup from splitting. By holding everything together it lets actives spread evenly, gives products a silky touch and extends shelf life.
The ingredient shows up often in sunscreens, cleansing balms and foundations but it is not as famous as workhorses like polysorbate 20, making it more of a behind-the-scenes helper than a headline star.
Safety data label it as low risk with rare cases of mild irritation or allergy. Formulas that use it are generally well tolerated by all skin types. Still, skins differ so it is smart to do a quick patch test whenever you try a new product that contains this or any other unfamiliar compound.