The Cracking of Human Hair Cuticles by Cyclical Thermal Stresses
January 1998
New to Hair Fibers? There is a guide in the encyclopedia. Read the guide → Studysummary This study found that repeated cycles of wetting and blow-drying hair fibers can cause cracks in the hair cuticles, particularly among individuals who frequently blow-dry their hair. Our plain-language summary of this paper — not a Tressless recommendation.
The study investigated the effects of cyclical wetting and blow-drying on hair fibers, revealing that these processes caused multiple cracks in the hair cuticles, aligned parallel to the hair fiber's longitudinal axis. These cracks initiated at the cuticle ends near the cortex and propagated outward, limited to the size of one cuticle. Cracks also appeared in hidden cuticle layers due to reduced hydration, making the outer cuticles rigid and brittle. Analysis of hair from 100 individuals showed that cracks were prevalent in those who frequently blow-dried their hair, leading to significant cuticle breakage during combing. The study also discussed the impact of certain cosmetic products on crack formation.
