10 citations,
October 2001 in “PubMed” The conclusion is that substances can penetrate hair fibers through multiple pathways, including both the cell membrane complex and the non-keratinous parts.
January 2024 in “Uttar Pradesh journal of zoology” Chemical treatments severely damage hair cuticles, especially in previously treated hair.
10 citations,
June 2001 in “International Journal of Cosmetic Science” Natural shampoos made in the lab conditioned hair better than commercial ones with chemicals.
1 citations,
November 2023 in “Cosmetics” Surfactants damage hair, but sealing the cuticle can prevent this.
4 citations,
December 2018 in “Macedonian Journal of Chemistry and Chemical Engineering” A new method accurately measures amino acids in treated hair, showing bleaching reduces amino acids while protein treatments increase them.