Integral Hair Lipid in Human Hair Follicle
August 2011
in “
Journal of dermatological science
”
Integral hair lipid IHL lipid envelope hair cuticle inner root sheath epidermal lipid layer fatty acids phytosphingosine ceramides 18-methyl-eicosanoic acid oxidative stress hair treatments bleaching perming photochemical changes lipid metabolism hair lipid lipid layer hair damage hair growth hair function
TLDR Human hair has a protective lipid layer that can be damaged by moisture and treatments, affecting hair growth and health.
The document from December 2011 discusses Integral hair lipid (IHL), which is a component of the human hair follicle that creates a lipid envelope, contributing to the hair's resistance to environmental factors. IHL is primarily found on the hair cuticle and inner root sheath and functions similarly to the epidermal lipid layer that acts as a skin barrier. The major constituents of IHL are fatty acids, phytosphingosine, and ceramides, with fatty acids being the most abundant, particularly 18-methyl-eicosanoic acid, which is bound to proteins. IHL is susceptible to damage from moisture, solvents, oxidative stress from hair treatments like bleaching or perming, and photochemical changes. The metabolism of lipids is crucial not only for the maintenance of the hair's lipid envelope but also for hair growth and function.
