Emulsifier

Polyglyceryl-3 Diisostearate

Reviewed by Rosie · Last updated 18 Aug 2026

Also known as: Isostearic Acid, Stearic Acid

Blend of isostearic acid and glycerin derivative | Primarily used as an emulsifier

At a glance

May feed Fungal Acne

Things to be aware of

May cause Acne Can worsen Oily Skin

Addresses

Dehydration

What Is Polyglyceryl-3 Diisostearate?

Polyglyceryl-3 diisostearate is primarily used as an emulsifier in cosmetics. Its lightweight feel and soft emolliency make it a desirable option to pair with or use in place of heavier emulsifiers. This ingredient also has cleansing properties but isn’t typically used for that purpose. It may be synthetic or plant-derived (the type uses) or, to a lesser extent, animal-derived.

Polyglyceryl-3 diisostearate is considered a diester (a chemical formed by reacting an acid with two alcohols) of the fatty acid isostearic acid and humectant polyglycerin-3.

Use levels of polyglyceryl-3 diisostearate in cosmetics range from 2–5%, depending on formulary needs. It’s insoluble in water but mixes readily with oils.

Clinical Evidence & References

Published Research

  • Colloids and Surfaces, June 2017, pages 279–286 [https://www.sciencedirect.com/science/article/abs/pii/S0927775717302340]
  • International Journal of Toxicology, August 2023, pages 5S–101S [https://journals.sagepub.com/doi/10.1177/10915818231174440]
  • Scientific Reports, March 2023, pages 1–14 [https://www.nature.com/articles/s41598-023-31379-0]

How widely it's used

1.8%
of skincare products contain this ingredient — placing it in the top 50% of most-used ingredients.
Most common in: Sunscreens

Regulatory information

Standardised cosmetic-ingredient identifiers used by regulators.

Show identifiers
INCI Name
POLYGLYCERYL-3 DIISOSTEARATE
EC Number
- / -
Function
Emulsifying

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