In this study, a polyphenol and biotin supplement improved skin roughness and significantly reduced hair shedding, but did not demonstrate clear superiority over placebo in overall skin outcomes.
September 2017 in “Journal of Investigative Dermatology” This study found that after four weeks of daily use, the roughness of the hair surface significantly decreased, as shown through quantitative image analysis using HIROX.
19 citations
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July 2018 in “ACS biomaterials science & engineering” This study showed that chemical and mechanical treatments significantly alter the nanoscale surface properties of hair, affecting its roughness, mechanical stiffness, adhesion, and surface potential.
10 citations
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January 2020 in “Royal Society Open Science” This study developed a quantitative measure for scoring hair surface damage from SEM images and found it accurately classified hair damage caused by explosive blasts, similar to an existing classification system.
161 citations
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July 2003 in “ACM Transactions on Graphics” In this study, a new shading model for hair was developed that better matches real-life light scattering, thanks to detailed new measurements of hair fiber scattering not predicted by existing models.
This study introduced a new hair shading model that more accurately simulates light scattering on hair fibers, capturing effects not predicted by previous models.
52 citations
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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.
20 citations
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July 2010 in “Skin Research and Technology” This study found that aging in Korean individuals is associated with changes in hair diameter and surface structure, as observed through atomic force microscopy.
7 citations
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July 2004 in “International Journal of Cosmetic Science” Different hair types from various ethnic groups affect hair shine due to characteristics like thickness and shape.
1 citations
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September 2017 in “Journal of Investigative Dermatology” This study reported that introducing the TERT and Bmi1 genes into mouse dermal papilla cells resulted in immortal cells capable of inducing new hair follicles in vivo, and human immortal DPCs were also developed.
April 2023 in “Journal of Investigative Dermatology” In this study, the researchers found that a combination of honeys from four islands significantly repaired hair integrity, porosity, and surface roughness caused by UV-A and urban pollution, resulting in strengthened, soft, and shiny hair in Asian hair shafts.
September 2017 in “Journal of Investigative Dermatology” Certain products and treatments can improve hair health and growth.
This review highlights that surface mechanical regulation can program macrophage behavior through specific mechanical cues on material surfaces, potentially advancing immunotherapies and regenerative medicine by enabling precise control over macrophage functions.
January 2008 in “대한미용학회지” This study reports that prolonged UV irradiation causes progressive damage to the hair's keratin structure, leading to increased surface roughness, cuticle destruction, and decreased tensile strength in young women’s hair.
September 2024 in “Journal of Cosmetic Dermatology” This study found that quercetin-loaded solid lipid nanoparticles demonstrated positive protective effects on human hair against UV-B light, as they controlled microscopic surface roughness, reduced chemical changes, and minimized protein loss in vitro compared to other treatments.
May 2026 in “The Scientific Issues of Ternopil Volodymyr Hnatiuk National Pedagogical University Series pedagogy” This study conducted a comprehensive analysis of methods for assessing surface roughness, highlighting that contact methods using profilometers provide accurate results for machine parts, while non-contact optical and laser methods offer high precision and efficiency without damaging surfaces.
99 citations
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July 2005 in “Ultramicroscopy” This study analyzed the nanotribological properties of various hair types and human skin, revealing differences in friction and adhesion based on ethnicity and hair condition.
51 citations
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March 2001 in “Clinics in dermatology” This study found that bleach treatments significantly increased hair surface roughness and decreased Young's modulus, indicating marked changes in hair's molecular structure which may affect future hair-care product formulation.
13 citations
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March 2006 in “International Journal of Cosmetic Science” The study found that a polymer treatment changes the charge on hair surfaces, making bleached hair smoother and less porous.
July 2024 in “Experimental Dermatology” This study suggests that APC collagen peptides may accelerate hair growth and promote overall hair health by enhancing cellular proliferation and activating specific signaling pathways in human and mouse models.
4 citations
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July 2020 in “International Journal of Cosmetic Science” This study found that while all hair removal techniques increased axillary erythema and skin dryness, shaving caused less erythema but more dryness than plucking or waxing, without affecting post-inflammatory hyperpigmentation or other skin properties.
September 2024 in “Heliyon” In this study, researchers observed that even a single session of hair dyeing can damage hair fibers, with significant worsening of mechanical properties and protein composition after three or more consecutive treatments, emphasizing the need to consider the cumulative impacts of dyeing on hair health.
3 citations
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July 2025 in “Acta Biomaterialia” In this study, AFM-based indentation was used to assess mechanical properties of murine skin wounds at two healing stages, revealing that early wounds exhibit stiffer hyperproliferative epithelium compared to granulation tissue, and highlighting significant influences of surface roughness on tissue stiffness measurements.
In this 24-week study, oral supplementation with hydrolyzed low-molecular-weight porcine placental peptides significantly improved scalp elasticity, hair diameter, tensile strength, surface roughness, and luster compared to placebo, suggesting its potential as a nutritional intervention for age-related scalp and hair changes.
April 2023 in “Journal of Investigative Dermatology” This study demonstrated that a combination of four types of honey significantly improved hair integrity, porosity, and surface roughness after exposure to UV-A and pollution stress.
November 2025 in “Advanced Healthcare Materials” This study found that incorporating CTA2-BADG, a modified hair-rebonding compound, into damaged hair significantly improved surface morphology and tensile strength by using charge-conversion chemistry to enhance penetration into the hair shaft.
24 citations
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January 2009 in “International Journal of Trichology” This review discusses the mechanisms by which sunlight exposure aggravates hair aging and highlights the role of hair pigments in providing photochemical protection, reporting no new results.
8 citations
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December 2003 in “Materials Research-ibero-american Journal of Materials” Polyquaternium 7® builds up on hair, improving its look and feel, and AFM is good for measuring these changes.
1 citations
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June 2023 in “Skin Research and Technology” This study found that two shampoos with different dyeing methods had varying abilities to dye hair and impact hair health, suggesting that individuals should select hair color shampoos based on their personal needs.
July 2024 in “International journal of agriculture and food sciences research.” This study found that a hair conditioner using peptides from Pneumatophorus japonicus heads improved damaged hair's structure, gloss, and smoothness more effectively than a commercial wheat protein conditioner by increasing amino acid content and interacting with hair keratin.