52 citations
,
February 2005 in “Biopolymers” Chemical hair straightening changes hair proteins and mostly fixes broken bonds.
45 citations
,
December 2006 in “Biopolymers” Permanent waving weakens hair by altering its protein structure.
25 citations
,
May 2019 in “Heliyon” Hair treatments cause significant structural changes, especially with excessive heat, regardless of ethnicity.
20 citations
,
December 2012 in “Journal of molecular structure” The study found that thioglycolic acid breaks down hair bonds more consistently than l-cysteine, which is less damaging to hair.
3 citations
,
April 2011 in “Microscopy research and technique” Teratoma hair is similar to scalp hair but has a rougher surface and lower adhesive force.