Beta-Sitosterol
What is Beta-Sitosterol?
Beta-Sitosterol is a plant-derived phytosterol, a naturally occurring sterol found in many vegetables, nuts, seeds, and vegetable oils such as avocados, rice bran, and soybeans. In skincare, it is valued for its emollient properties, ability to strengthen the skin's barrier function, and anti-inflammatory effects that help soothe irritated skin. It also acts as an antioxidant, protecting skin cells from oxidative stress caused by environmental factors.
Roles in Formulation
This ingredient serves the following purposes in cosmetic formulations:
Emollient
Softens and smooths skin by filling in surface roughness and improving slip; can also help reduce moisture loss when paired with occlusives and film formers.
Skin conditioning agent
Maintains skin softness, smoothness, and flexibility.
Antioxidant
Slows oxidation of oils, fragrances, and sensitive actives to improve shelf life and reduce rancidity or color change; sometimes also supports skin protection from oxidative stress.