Hair curl type, hair habits and scalp heath, part 1: Clinical studies.
- 1TRI Princeton, Princeton, New Jersey, USA.
- 2Newtone Inc, Princeton, New Jersey, USA.
Abstract
Background
Very curly, textured hair is often associated with specific scalp conditions, such as traction alopecia and seborrheic dermatitis. However, to date, very few detailed clinical studies have been performed to correlate scalp conditions to curl type and hair habits.Methods
Healthy female panelists, with hair not damaged by chemical treatment, were recruited in both the US and South Africa (SA) based on their natural curl type: wavy (Walker Type 2), curly (Walker Type 3) or kinky (Walker Type 4). Both scalp and hair assessments were performed at visit 1 (baseline) and at visit 2, 1 week afterwards. Between the visits, panelists were asked to wash their hair four times with a standard shampoo and conditioner selected and provided by the authors.Results
A significant proportion of panelists with Type 4 hair washed their hair less frequently than panelists with the other hair types and were more inclined to use hair styling techniques (braiding, extension, knots, etc.), which induce tension on the scalp. They also self-perceived having drier and less oily scalps than panelists with the other hair types. Dermatologists' assessments showed the incidence of seborrheic dermatitis was higher in Hair Type 4 in the US. Dermatologists observed the highest levels of traction alopecia in Hair Type 4 in both countries. Scalp image analysis showed that visible scalp scaling was more common in Type 4 hair versus other hair types in both the US and SA. Washing the hair every 2 days between the two visits improved self-perceived scalp cleanliness and scalp condition across all curl types in both countries.Conclusions
Our results confirm that more frequent use of specific styling practices in Type 4 hair is linked to higher levels of traction alopecia. Results also suggest that lower wash frequencies observed mainly with Type 4 hair were associated with a higher degree of scalp irritation and scaling and that washing hair more frequently has the potential to improve scalp health. Our data also suggest that scalp image analysis is a more consistent way of measuring scalp colour and scaling.
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BibTeX
@article{gourionarsiquaud2026hair,
title = {{Hair curl type, hair habits and scalp heath, part 1: Clinical studies.}},
author = {Samuel Gourion-Arsiquaud and Rezma Shrestha and Matthieu Jomier and Paul Cornwell},
journal = {International journal of cosmetic science},
year = {2026},
month = nov,
doi = {10.1111/ics.70114},
url = {https://europepmc.org/article/MED/42971785},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Hair curl type, hair habits and scalp heath, part 1: Clinical studies.
AU - Samuel Gourion-Arsiquaud
AU - Rezma Shrestha
AU - Matthieu Jomier
AU - Paul Cornwell
PY - 2026
DA - 2026/11/01
JO - International journal of cosmetic science
DO - 10.1111/ics.70114
UR - https://europepmc.org/article/MED/42971785
AB - Background Very curly, textured hair is often associated with specific scalp conditions, such as traction alopecia and seborrheic dermatitis. However, to date, very few detailed clinical studies have been performed to correlate scalp conditions to curl type and hair habits.Methods Healthy female panelists, with hair not damaged by chemical treatment, were recruited in both the US and South Africa (SA) based on their natural curl type: wavy (Walker Type 2), curly (Walker Type 3) or kinky (Walker Type 4). Both scalp and hair assessments were performed at visit 1 (baseline) and at visit 2, 1 week afterwards. Between the visits, panelists were asked to wash their hair four times with a standard shampoo and conditioner selected and provided by the authors.Results A significant proportion of panelists with Type 4 hair washed their hair less frequently than panelists with the other hair types and were more inclined to use hair styling techniques (braiding, extension, knots, etc.), which induce tension on the scalp. They also self-perceived having drier and less oily scalps than panelists with the other hair types. Dermatologists' assessments showed the incidence of seborrheic dermatitis was higher in Hair Type 4 in the US. Dermatologists observed the highest levels of traction alopecia in Hair Type 4 in both countries. Scalp image analysis showed that visible scalp scaling was more common in Type 4 hair versus other hair types in both the US and SA. Washing the hair every 2 days between the two visits improved self-perceived scalp cleanliness and scalp condition across all curl types in both countries.Conclusions Our results confirm that more frequent use of specific styling practices in Type 4 hair is linked to higher levels of traction alopecia. Results also suggest that lower wash frequencies observed mainly with Type 4 hair were associated with a higher degree of scalp irritation and scaling and that washing hair more frequently has the potential to improve scalp health. Our data also suggest that scalp image analysis is a more consistent way of measuring scalp colour and scaling.
SN - 0142-5463
SN - 1468-2494
ER -