Skin ages and changes due to sun, wind, and aging, causing dryness, thinning, and hair loss.
15 citations
,
August 2015 in “Scanning” Corkscrew and cigarette-ash-shaped hairs in tinea capitis are caused by internal hair degradation and external resistance.
3 citations
,
January 2015 in “Mathematical problems in engineering” Hair damage increases significantly with higher temperatures and longer heating times.
11 citations
,
January 2016 in “Biointerphases” The hair's outermost surface has multiple layers of lipids and proteins.
February 1999 in “The anatomical record” Two mouse mutants have defective hair cuticle cross-linking.
19 citations
,
July 2004 in “Australasian Journal of Dermatology” Her hair grew back normally after she stopped rubbing it.
59 citations
,
August 1981 in “PubMed” Trichilemmal keratinization is a unique process in hair follicles where the outer root sheath turns into keratin without a specific layer.
December 2025 in “Biopolymers” Heat worsens damage in chemically treated hair, especially bleached and straightened hair.
24 citations
,
January 2009 in “International Journal of Trichology” Sunlight exposure ages hair, making it brittle, stiff, and dry.
Cornification is the process where living skin cells die to create a protective barrier, and problems with it can cause skin diseases.
34 citations
,
September 2007 in “Experimental Dermatology” The outer layer of Merino wool is rich in sulfur proteins, making it resistant to damage.
17 citations
,
February 2015 in “Cell Death and Disease” Inhibiting AP1 in mice skin causes structural changes and weakens the skin barrier.
16 citations
,
April 2012 in “Journal of mammalogy” Young female Australian fur seals are losing hair due to low tyrosine and zinc levels and high pollution exposure.
27 citations
,
May 2019 in “Cosmetics” The hair cuticle is made of tough proteins that protect the hair, but more research is needed to fully understand its structure.
June 2026 in “Communications Biology” Hoxc13 and hair keratin are needed for forming rough skin on frog mating pads.
2 citations
,
January 1987 in “PubMed” Woolly hair syndrome is a genetic condition causing frizzy, fragile hair.
9 citations
,
May 2005 in “Annales de dermatologie et de vénéréologie” Oral zinc and topical steroids can effectively treat chronic scalp pustules and hair loss in elderly patients.
January 2008 in “대한미용학회지” UV exposure severely damages hair, making it rough and weak.
7 citations
,
November 2004 in “International Journal of Cosmetic Science” Hair breaks differently when wet or dry and is affected by its condition and treatments like perms and bleaching.
5 citations
,
November 2021 in “The journal of investigative dermatology/Journal of investigative dermatology” Wnt/β-catenin signaling is important for keeping skin cell attachment structures stable.
January 2005 in “Seibutsu Butsuri/Seibutsu butsuri” Chemical treatments damage hair more than UV exposure, making it thinner and less flexible.
May 2026 in “Applied Spectroscopy” Humidity affects hair structure changes during stretching.
4 citations
,
November 2016 in “The Journal of Dermatology” Pili torti hair is fragile due to loose keratin filaments and weak disulfide bonds.
3 citations
,
January 2021 in “Wear” Hair's resistance to wear varies by ethnicity and treatment, with less wear indicating stronger hair.
10 citations
,
November 2016 in “International Journal of Cosmetic Science” A tough membrane between the outer and inner layers of human hair protects it from damage.
1 citations
,
May 1983 in “Acta dermato-venereologica” The hairpiece matted due to weathered hair after shampooing.
August 2024 in “Microscopy Research and Technique” The study identifies the pheromone gland's location and structure in Endoclita vietnamensis, aiding future pest control methods.
February 2019 in “PubMed” The research found that twisting hair fibers can show changes in stiffness and damage, and help tell apart different hair treatments.
May 2022 in “Experimental dermatology” Trichothiodystrophy hair is structurally abnormal with protein and organization issues.
November 2025 in “Open Repository of the University of Porto (University of Porto)” Continuous use of finasteride and minoxidil is effective for treating androgenetic alopecia.