52 citations,
February 2005 in “Biopolymers” Chemical hair straightening changes hair proteins and mostly fixes broken bonds.
52 citations,
August 1978 in “Journal of Applied Polymer Science” Human hair's ability to get wet is complex and can change with treatments, damage, and environment.
45 citations,
December 2006 in “Biopolymers” Permanent waving weakens hair by altering its protein structure.
42 citations,
January 2011 in “Journal of Biomedical Optics” Infrared and Raman imaging can non-destructively analyze hair structure and help diagnose hair conditions.
34 citations,
October 1982 in “Journal of applied polymer science” Moisture content significantly affects how human hair breaks.
31 citations,
December 2002 in “Biochimica et biophysica acta. G, General subjects/Biochimica et biophysica acta. General subjects (Online)” The research found two types of calcium in human hair, one that varies among individuals and another that is consistent across people.
30 citations,
September 2018 in “International Journal of Cosmetic Science” Bleaching hair causes severe structural and chemical damage, including protein loss and oxidation.
27 citations,
January 1995 Melanin in black hair protects it from sun damage better than light-brown hair.
27 citations,
June 2017 in “Expert opinion on investigational drugs” New anti-acne medications are being tested to offer alternatives to current treatments.
24 citations,
November 2015 in “Scientific reports” Human hair has a new region with ordered filaments and the cuticle contains β-keratin sheets.
22 citations,
March 2018 in “American Journal of Clinical Dermatology” New acne treatments show promise as alternatives to traditional therapies.
20 citations,
January 2003 in “Journal of oleo science” Chemical treatments and daily stresses damage hair, especially the cuticle layer.
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.
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.
18 citations,
August 2014 in “Lipids” Human hair has more unsaturated fats inside than on the surface, and certain lipids may help bind the outer and inner layers together.
18 citations,
November 2010 in “Journal of morphology” Antler velvet hair and body hair of red deer have different structures that help with protection and insulation.
18 citations,
January 1994 in “Skin pharmacology and physiology” Sunlight damages hair, causing cuticle loss, protein changes, and discoloration.
17 citations,
June 2012 in “Journal of experimental zoology. Part B, Molecular and developmental evolution” Hair in mammals likely evolved from glandular structures, not scales.
15 citations,
August 2020 in “Analytical chemistry” Hair lipids do not protect against humidity.
15 citations,
May 2010 in “International Journal of Cosmetic Science” The cell membrane complex in mammalian hair has three distinct types with different structures and chemical properties.
15 citations,
February 1999 in “The anatomical record” Some mutant mice have hair with abnormal cross-linking, mainly in the cuticle, not affecting other hair parts.
14 citations,
December 2016 in “PloS one” Keratin 26 affects cashmere goat hair growth and is influenced by various treatments.
13 citations,
March 2019 in “Journal of cosmetic dermatology” Heat damages hair, with Asian hair losing more protein than Caucasian hair.
12 citations,
February 2019 in “Skin research and technology” White hair has less lipid content and absorbs water differently than brown hair.
12 citations,
July 2016 in “Forensic science international” The research found that postmortem root bands in hair are likely caused by the breakdown of a specific part of the hair's inner structure after death.
11 citations,
January 2000 in “Journal of cosmetic science” Hydrolyzed wheat proteins penetrate all hair types effectively.
10 citations,
January 2012 in “Journal of biomedical optics” Melanin density affects hair color, and this method can help in cosmetic assessments and diagnosing hair diseases.
10 citations,
January 2002 in “Nihon Keshouhin Gijutsushakaishi/Journal of S C C./Nihon Keshouhin Gijutsushakai kaishi” The cuticle significantly contributes to hair stiffness, making up about 60% of the total bending stress.
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.
9 citations,
April 2019 in “Journal of structural biology” Hair's internal fibers are arranged in a pattern that doesn't let much water in, and treatments like oils and heat change how much water hair can absorb.