28 citations
,
November 2009 in “Journal of Structural Biology” High flux X-ray beams quickly damage the structure of human hair.
53 citations
,
September 1999 in “Journal of Synchrotron Radiation” Keratinous tissues have multiple structural layers, including ordered keratin and lipid granules.
28 citations
,
July 2000 in “PubMed” Hair structure forms the same way inside and outside the body.
22 citations
,
January 2006 in “Journal of Structural Biology” Hair follicles form hard α-keratin filaments in four steps, showing structural differences.
24 citations
,
November 2015 in “Scientific reports” Human hair has a new region with ordered filaments and the cuticle contains β-keratin sheets.
37 citations
,
October 2015 in “PeerJ” Perming significantly changes hair's molecular structure, while shampoo and conditioner do not.
8 citations
,
January 2020 in “PeerJ” Alopecia Areata causes significant structural and compositional changes in hair.
65 citations
,
May 2006 in “Journal of Structural Biology” Hair curliness is due to uneven distribution of different cortices within the hair fiber.
29 citations
,
April 2003 in “Experimental dermatology” Human hair follicles grown in vitro maintain normal keratin patterns and structure.
40 citations
,
May 2016 in “Proceedings of the National Academy of Sciences of the United States of America” Changes in keratin make hair follicles stiffer.
2 citations
,
February 2016 in “Journal of sol-gel science and technology” A small molecule can strengthen fine hair, making it more resistant and natural-feeling.
1 citations
,
January 2023 in “International journal of all research education and scientific methods” Hair analysis is better than urine and blood for detecting past drug use.
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.
Understanding hair surface properties is key for effective hair care products.
30 citations
,
July 2000 in “PubMed” Hair has unevenly distributed proteins and lipids, with lipids mainly in the cuticle and proteins in the cortex and medulla.
March 2025 in “The Open Dermatology Journal” Trichorrhexis nodosa is common hair breakage, often due to styling, and new treatments are being explored.
12 citations
,
December 2011 March 2026 in “Journal of the mechanical behavior of biomedical materials/Journal of mechanical behavior of biomedical materials” Hair cuticles remain stable and resilient under stress due to strong protein content and crosslinking.
April 2025 in “Pharmaceuticals” APA is a promising new compound for repairing damaged hair, outperforming Olaplex® in strength and elasticity.
66 citations
,
June 2004 in “Biophysical Journal” Hard α-keratin in hair has a unique, nonordered structure, different from other fibers.
63 citations
,
December 1998 in “Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology” The study improved understanding of keratin fiber structure by showing consistent microfibril diameter but varying distances and electron density profiles.
52 citations
,
January 2005 in “International journal of experimental pathology” Melatonin may reduce skin damage caused by X-rays in rats.
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.
23 citations
,
October 2007 in “International journal of cancer” X-ray diffraction of hair might help detect breast cancer non-invasively.
11 citations
,
March 2023 in “Frontiers in Nutrition” Hair analysis can detect small changes in dietary zinc intake.
10 citations
,
January 1985 in “PubMed” Trace elements like calcium, iron, and zinc are unevenly distributed in hair, while sulfur is even, and increased phosphorus and potassium levels are linked to skin reactions.
9 citations
,
June 2020 in “European Radiology Experimental” 15-Gy x-ray irradiation temporarily alters rat calvaria skin without causing significant inflammation or fibrosis.
9 citations
,
January 2011 in “Journal of X-ray science and technology” Perming and bleaching damage hair differently, with bleached hair having more cysteic acid in the cuticle.
8 citations
,
September 2014 in “Journal of X-Ray Science and Technology” High calcium levels in hair may indicate early breast cancer.
8 citations
,
July 2002 in “X-Ray Spectrometry” Elemental composition of hair affects its x-ray diffraction patterns.