Mineral Oil is a highly refined mixture of saturated hydrocarbons (primarily alkanes and cycloalkanes) derived from petroleum and extensively purified for cosmetic and pharmaceutical use. In skincare, cosmetic-grade Mineral Oil functions primarily as a powerful occlusive agent, forming an inert, semi-permeable film on the skin surface that significantly reduces transepidermal water loss (TEWL). This mechanism makes it particularly effective in restoring barrier integrity in compromised or severely dry skin. Due to its chemical stability, non-reactivity, and resistance to oxidation, Mineral Oil does not degrade or generate reactive byproducts, contributing to excellent shelf stability and predictable performance across a wide range of formulations, including those designed for sensitive or post-procedure skin.

In haircare applications, Mineral Oil is valued for its lubricating and protective properties, especially in products formulated to reduce friction, improve combability, and enhance surface smoothness of the hair fiber. By coating the cuticle, it helps minimize moisture loss and mechanical damage, leading to reduced breakage and frizz. Although it does not penetrate the hair shaft or deliver biological nutrients, its uniform film-forming behavior improves hair manageability and shine. These characteristics make Mineral Oil a frequent component in conditioners, hair oils, scalp protectants, and styling products where long-lasting softness and barrier protection are desired.