18 citations,
January 1994 in “Skin pharmacology and physiology” Sunlight damages hair, causing cuticle loss, protein changes, and discoloration.
4 citations,
January 2017 in “Annals of Dermatology” Frequent hairdryer use may worsen hair fragility in people with Pili Annulati.
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.
9 citations,
April 2019 in “Journal of structural biology” Hair's internal fibers are arranged in a pattern that doesn't let much water in, and treatments like oils and heat change how much water hair can absorb.
68 citations,
August 2014 in “PeerJ” Human hair proteins vary by individual, body site, and ethnicity, useful for forensics.