191 citations,
November 1959 in “Annals of the New York Academy of Sciences” Hair and wool have complex microscopic structures with microfibrils and varying cystine content.
January 2013 in “Sen'i Gakkaishi” Microfibrils are key for permanent waves, and hydrolyzed keratin improves wave formation and hair condition.
19 citations,
January 2009 in “International review of cell and molecular biology” Hair's strength and flexibility come from its protein structure and molecular interactions.
November 2024 in “Biophysical Chemistry” Hair structure changes immediately during perm treatment, with initial damage partially restored later.
Oxidized hair can naturally regain strength and stability over six months.