TLDR Frequent blow-drying causes cracks and breakage in hair cuticles.
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.
27 citations,
January 1995 Melanin in black hair protects it from sun damage better than light-brown hair.
12 citations,
July 2015 in “British journal of dermatology/British journal of dermatology, Supplement” Curly hair breaks due to mechanical damage and environmental factors, not chemical makeup, and needs ongoing care to prevent breakage.
20 citations,
January 2015 in “Journal of cosmetic dermatology” Older people's hair cuticles get more easily damaged and lose protective oils, especially in their 40s and 50s.
85 citations,
October 2007 in “International Journal of Dermatology” Curly hair shape is due to uneven growth patterns in the hair follicle.
March 2007 in “International Journal of Cosmetic Science” Hair with more melanin resists weather damage better.
7 citations,
November 2004 in “International Journal of Cosmetic Science” Hair breaks differently when wet or dry and is affected by its condition and treatments like perms and bleaching.
27 citations,
February 1991 Cuticle damage doesn't affect hair's tensile strength; the cortex is responsible for it.