Hair Lipid Structure: Effect of Surfactants

Human hair is primarily composed of proteins and lipids, which are crucial for protecting hair against damage and maintaining its health. The document discusses the role of these lipids in hair properties and the effects of surfactants, found in shampoos and conditioners, on hair lipid depletion. Surfactants remove lipids during routine hair cleansing, but they do not completely eliminate all free lipids. The impact of surfactants on hair lipids is complex and not well understood. Hair lipid content varies by ethnicity and is affected by aging, chemical and environmental damage, and treatments like bleaching and dyeing. Studies have shown that one-time shampooing can remove approximately 50% of total extractable lipids from hair, and 70-90% can be removed with repeated shampooing. Lipid-based hair care products can restore hair lipids lost by damaging processes and improve hair surface texture and shine. Further research is needed to improve the effectiveness of surfactants and limit potential damage.