5 citations,
October 2003 in “PubMed” Chemical treatments and light exposure damage hair proteins.
12 citations,
December 2017 in “Food and chemical toxicology” Permanent hair dye mixtures can irritate and damage the skin.
84 citations,
April 2015 in “Cosmetics” Hair dyes vary in how long they last and how deeply they penetrate hair.
July 2020 in “International Journal of Cosmetic Science” The study found that minor protein differences between curved and straight Japanese hair are unlikely to significantly affect hair structure.
11 citations,
January 1987 in “Electrophoresis” Keratin proteins are consistent across different hair types from the same person.