Editor’s note:Cosmetics & Toiletries is pleased to welcome Robert J. Dorin, DO, to its lineup of contributors. His articles will provide insights on hair biology in relation to cosmetics and personal care product development.
Hair is a biological fiber composed primarily of dead keratinocytes that fulfill a variety of important roles for mammals—including, but not limited to, insulation, tactile and sensory functions. Of particular interest to humans are the profound effects it has on the perception and portrayal of a persona. Hair, to a large extent, is an extension of identity. It provides vitality and confidence to portray one’s “style” to others. With such far-reaching dynamic psychosocial implications, it is no wonder why such importance is placed on understanding and promoting intrinsic and extrinsic factors that support the health of hair, as well as preventing harm to this coveted biological fiber.
Research traditionally has focused on the inanimate portion of hair, i.e., beyond the follicle, in order to elucidate the physical and chemical properties and characteristics of hair fibers—all with the intent to produce effective shampoos, conditioners, dyes, bleaching agents, perming agents and the like to help enhance hair’s appearance and combat the perception of aging hair. While decades of this research have proven invaluable to the scientific community, and will continue to do so, a paradigm shift has occurred toward understanding the living component within the hair follicle. A molecular biology revolution has emerged, and promises new strategies in understanding and potentially combating the aging process of hair cells.
This article will consider effects and possible mechanisms of aging in the hair follicle as they relate to the senescence of hair characteristics, hair stem cells and canities. It also will look at a recent study elucidating the effects of bleaching, specifically on inanimate black human hair fibers. Finally, it will cover anti-aging and the concept of antioxidants in human hair.