3 citations
,
January 2018 in “International Journal of Cosmetic Science” Hair stiffness increased by 13.2% after caffeine treatment, validating the Stiffness-Angle Law as an effective measurement method.
31 citations
,
February 2019 in “International Journal of Cosmetic Science” Caffeine applied to the scalp can protect hair follicles from UV damage.
6 citations
,
May 2020 in “Molecules/Molecules online/Molecules annual” Yak belly hair has higher porosity and is less stiff than human hair, making it absorb dye better but less suitable as a direct substitute for hair dyeing.
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.
August 2025 in “bioRxiv (Cold Spring Harbor Laboratory)” Root hair stiffness is mainly influenced by tip compression and turgor pressure.