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SourcesThe studies behind what we say about hair breakage

Where this comes from.

4 claims · 7 studies.

C17-1
Curl arises from asymmetric cell differentiation in the hair root, producing an elliptical cortex; mechanism structurally the same across ethnic origin, more pronounced in coily hair.
VerifiedOne source behind this claim
The record
Human hair keratin network and curvature.
Thibaut S, Barbarat P, Leroy F, Bernard BA · 2007 · International journal of dermatology 46 Suppl 1:7-10
PMID 17919197DOI
C17-2
African/African-diaspora scalp hair is significantly more curled on average than European or East Asian hair.
VerifiedOne source behind this claim
The record
Quantifying variation in human scalp hair fiber shape and pigmentation.
Lasisi T, Ito S, Wakamatsu K, Shaw CN · 2016 · American journal of physical anthropology 160:341-52
PMID 26955790DOI
C17-4
Coily/African-type hair shows lower water sorption and distinct cuticle lipid structure vs straighter hair; fragility best attributed to knotting/crack formation rather than cross-sectional shape alone.
VerifiedOne of 3 sources behind this claim · see the others
The record
How different is human hair? A critical appraisal of the reported differences in global hair fibre characteristics and properties towards defining a more relevant framework for hair type classification.
Daniels G, Fraser A, Westgate GE · 2023 · International journal of cosmetic science 45:50-61
PMID 36374002DOI
VerifiedOne of 3 sources behind this claim · see the others
The record
Ethnic hair: Thermoanalytical and spectroscopic differences.
Oliver MA, Coderch L, Carrer V, Barba C, Marti M · 2020 · Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging (ISSI) 26:617-626
PMID 32162430DOI
VerifiedOne of 3 sources behind this claim · see the others
The record
External lipid function in ethnic hairs.
Coderch L, Oliver MA, Carrer V, Manich AM, Martí M · 2019 · Journal of cosmetic dermatology 18:1912-1920
PMID 30866162DOI
C17-5
Coconut oil (unlike mineral or sunflower oil) penetrates the hair shaft, measurably reduces protein loss from grooming, correlates with lower Hair Breakage Index.
VerifiedOne of 2 sources behind this claim · see the other
The record
Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage.
Rele AS, Mohile RB · 2003 · Journal of cosmetic science 54:175-92
PMID 12715094
VerifiedOne of 2 sources behind this claim · see the other
The record
Hair breakage index: an alternative tool for damage assessment of human hair.
Mhaskar S, Kalghatgi B, Chavan M, Rout S, Gode V · 2011 · Journal of cosmetic science 62:203-7
PMID 21635848
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