What it is
Hydrogenated castor oil is made by adding hydrogen to castor oil, converting its unsaturated fatty acids into a hard, waxy, more stable material. In formulas it functions as a thickening and structuring agent, an emollient, and a stabilizer for emulsions and suspensions. It is widely used in sticks, balms, and creams, including sunscreen formats, to build body and a smooth texture.
Safety & warnings
Hydrogenated castor oil has a long record of safe cosmetic use and is generally well tolerated. As a castor-derived wax it is sometimes noted as having low-to-moderate comedogenic potential for very acne-prone skin, though it is widely used without issue. It is not a fragrance allergen.
Origin & sourcing
Derived from castor oil, which is pressed from the seeds of the castor plant (Ricinus communis), then chemically hydrogenated into a saturated wax.
Questions everyone asks
Why is hydrogenated castor oil added to sunscreen?
It thickens and structures the formula and adds emollience, helping create stable creams, balms, and sticks with a smooth, even texture.
Is hydrogenated castor oil the same as regular castor oil?
No. It is castor oil that has been hydrogenated into a hard, waxy solid, which changes it from a liquid oil into a structuring and stabilizing ingredient.