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The behavior of hair from different countries
Crystal E Porter1, Felicia Dixon, Cho-Cho Khine
1L'Oréal USA- L'Oréal Institute for Ethnic Hair and Skin Research, Chicago, IL, USA.
Journal of Cosmetic Science
|May 20, 2009
Summary
Curly hair properties vary significantly by country of origin, with curlier hair often being more fragile. These differences in hair characteristics, including protein markers and thermal behavior, may impact treatment responses.
Area of Science:
- Cosmetic Science
- Materials Science
- Human Biology
Background:
- Curly hair exhibits diverse properties influenced by genetics and environment.
- Understanding these variations is crucial for developing effective hair care products and treatments.
- Previous research has not fully explored the geographical impact on curly hair characteristics.
Purpose of the Study:
- To investigate the relationship between the degree of curl and physical properties of hair from different countries.
- To identify variations in hair protein markers and thermal behavior based on geographical origin.
- To explore potential links between hair characteristics, geographical origin, and response to treatments.
Main Methods:
- Geometrical measurements using a laser scanning micrometer and a novel hair shape classification.
- Mechanical analysis through tensile testing.
- Biochemical and thermal analysis using 2-D gel electrophoresis and differential scanning calorimetry (DSC).
Main Results:
- Hair characteristics are significantly influenced by the degree of curl; curlier hair demonstrated increased fragility.
- A distinct correlation was observed between the degree of hair curl and country of origin.
- Differential scanning calorimetry (DSC) and 2-D gel electrophoresis revealed differences in thermal behavior and protein markers.
- Variability in hair properties was linked to regional and cultural diversities.
Conclusions:
- The degree of curl is a key determinant of hair properties, including fragility.
- Geographical origin is a significant factor influencing curly hair characteristics, including protein composition and thermal properties.
- Observed hair variations may impact treatment efficacy and highlight the role of population diversity.
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