A Systematic Review on the Lipid Composition of Human Hair

This systematic review examines the lipid composition of human hair, highlighting variations by ethnic hair type and hair layer. Lipids in the hair shaft's cuticle, cortex, and medulla protect against environmental and chemical damage, prevent breakage, and influence hair's elastic and tensile properties. The review includes 59 articles and finds that lipid loss, accelerated by treatments like bleaching, dyeing, perming, straightening, and exposure to surfactants, sun, and aging, leads to dehydrated, breakable, and dull hair. Elevated hair lipid levels are associated with diseases such as acne, alopecia, and various cancers. The study underscores the importance of lipids in maintaining healthy hair and calls for further research on the impact of lipids on ethnic hair and changes due to dermatologic and systemic diseases.