2 citations
,
July 2013 in “Fashion business” Keratin essence protects and improves damaged hair.
1 citations
,
April 2021 in “Han'gug miyong haghoeji/Journal of the Korean society of cosmetology” Aspartic acid at 0.75% makes perms more effective and less damaging to hair.
May 2009 in “International Journal of Cosmetic Science” Permanent waving damages hair protein and weakens hair, especially with repeated treatments using sodium thioglycolate.
3 citations
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August 2008 in “PubMed” Repeated digital perming with sodium thioglycolate lotion significantly damages hair protein and structure.
2 citations
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September 2010 in “Journal of the Korea Academia-Industrial cooperation Society” Using 2% collagen in perms reduces hair damage while keeping curls.