An emulsifier is used to hold oil- and water-based ingredients together, keeping them from separating. As such, emulsifiers are commonly used in cosmetic preparations.
Humectant’s are used to increase skin’s moisture content. These ingredients attract water to the skin because they have an affinity for it. Common humectants include: glycerin, sorbitol, and hyaluronic acid.
Antioxidant refers to the ability of an ingredient to slow down, prevent, or block oxidation caused by the damaging effects of free radical activity. The skin has its own antioxidant defense systems, but when the concentration of free radicals is greater than the capacity of the skin’s natural defense system, cellular damage occurs. Antioxidants are added to cosmetics to increase the skin’s ability to protect against oxidation.
Collagen is the most abundant protein in the human body, making up about 25-35% of the entire body’s protein content. At this time, researchers have identified 28 types of collagen. Types I and V are those found in skin. Collagen is a structural protein found in the extracellular space. In the skin, collagen imparts strength and elasticity. As we age, our body’s collagen production begins to slow, causing wrinkles, sagging skin, etc.
Comedogenic means tending to cause blackheads, whiteheads, etc. by blocking the pores.
Desquamation, as it applies to skin health, is the shedding of the outermost layer of the skin’s surface. This is a natural and healthy process of the skin. When functioning normally, shells are shed individually and unnoticeably. Disturbances of this process can cause peeling and flakiness.
Corneocytes are differentiated keratinocytes which compose most of the stratum corneum, the outer part of the epidermis. Below you see a rendering of the stratum corneum.
Corneocytes are replaced through the process of desquamation and renewed from the lower epidermal layers. Corneocytes are essential to the skin’s barrier function.