5 citations
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October 2007 in “PubMed” Amino acids in conditioners improve hair strength, hydration, and color retention.
2 citations
,
January 1981 High temperatures and certain chemicals can significantly change the amino acid content in human hair.
24 citations
,
April 2016 in “Experimental Dermatology” Chemical treatments like dyeing, perming, and bleaching damage hair by altering amino acids and lipids.
4 citations
,
August 2014 in “Journal of molecular structure” Chemical treatments on bleached black hair change its internal structure by breaking and reforming bonds, and treatments with hydrolyzed eggwhite protein help repair it.
52 citations
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February 2005 in “Biopolymers” Chemical hair straightening changes hair proteins and mostly fixes broken bonds.