Diversity of hair growth profiles

  title={Diversity of hair growth profiles},
  author={Genevi{\`e}ve Loussouarn and Charles el Rawadi and Gilles Yves Genain},
  journal={International Journal of Dermatology},
The appearance of hair differs among the different populations of the world. Do these differences in appearance reflect physiological differences in the growth of the hair? Hair growth parameters have been studied most often in Caucasian hair. 1–9 Very few studies comparing African or Asian and Caucasian hair are available. 10–13 Accordingly, the present work aimed to evaluate and compare the hair growth characteristics of young adult African, Asian and Caucasian volunteers. Although we realize… 
Asian Hair: A Review of Structures, Properties, and Distinctive Disorders
The characteristics and properties of Asian hair are reviewed and hair disorders including linear lupus panniculitis and pseudocyst of the scalp that occur distinctively in Asian populations are discussed.
Age‐dependent changes in eumelanin composition in hairs of various ethnic origins
The age‐dependent modification of the PDCA/PTCA ratio, a marker for 5,6‐dihydroxyindole units in eumelanin, suggests a chronological evolution of hair follicle melanocyte phenotype (e.g. decrease in dopachrome tautomerase expression).
Histopathology of aging of the hair follicle
Graying happens in most individuals, although in different grades and starting at different ages, it is related to a decrease in the number and activity of the melanocytes of the hair bulb, which eventually completely disappear from the bulb of the white hair.
Hair care practices and structural evaluation of scalp and hair shaft parameters in African American and Caucasian women
The differences in hair care practices and hair fiber morphology among African American women may contribute to clinically observed variation in hair fragility and growth.
Ethnic Differences in Skin Physiology, Hair Follicle Morphology and Follicular Penetration
Investigation of skin physiological parameters, follicle morphology and the penetration process in different ethnic groups revealed that Caucasians had significantly larger terminal hair follicles than Asians and Africans, which may be explained by cultural habits.
Ageing-Related Features of Hair and Scalp in Chinese Women by Clinical Evaluation Study
Most aging features (hair diameter, scalpsebum contents, dandruff and erythema) were noticeable in their 40s, but hair density began to decline in their 30s, which would be helpful for understanding the ageing phenomenon and development of hair and scalp care products.
Relationships between hair growth rate and morphological parameters of human straight hair: a same law above ethnical origins?
Measurements of diameter, medulla and interscale distance show these parameters strongly correlated with hair growth rate, suggesting a common characteristic of human hair, at least for the straight or semi‐straight hair studied.
Development and Biology of East Asian Skin, Hair, and Nails
People of skin of color comprise the majority of the world’s population and Asian people comprise more than half of the total population of the world. East Asia encompasses a subregion of Asia that


Hair counts from scalp biopsy specimens in Asians.
Hair density is significantly lower in Koreans than in whites or blacks, and alight sexual difference exists in follicular counts in Koreans.
Periodicity in the growth and shedding of hair
Overall annual periodicity was demonstrated, manifested by a maximal proportion of telogen hairs at the end of summer and the beginning of autumn in men with or without alopecia.
Hair density in African Americans.
Hair density in African Americans is significantly lower than that in whites, which must be taken into consideration when evaluating a biopsy specimen from an African American patient.
Quantitative Analysis on the Scalp Hair Characteristics in Koreans using Phototrichogram
This study was performed to quantify Koreans' hair characteristics at each site (eg, vertex, occipital, temporal) of the scalp according to the age and sex using the phototrichogram and to compare the differences of hair characteristics between Caucasian and Korean population.
Phototrichogram analysis of Japanese female subjects with chronic diffuse hair loss.
Hair growth patterns of 101 Japanese female subjects with diffuse, chronic hair loss and 58 healthy Japanese female volunteers were categorized into subgroups using noninvasive quantitative methods
Observations on female scalp hair population, distribution, and diameter
The influence of the fiber number and diameter on the bulky appearance of the hair is often masked by other characteristics such as waviness and hair care practices.
  • J. Hamilton
  • Medicine
    Annals of the New York Academy of Sciences
  • 1951
Type or categories of scalp hairiness which can be used as standards for classitication and grading of the extent of common baldness are established and the relationship of scdp types to factors which influence the development of baldness is studied.
The unit area trichogram in the assessment of androgen‐dependent alopecia
The unit area trichogram was defined in the frontal and occipital areas often normal men and ten normal women and the results compared with the findings in ten male and fifteen female patients with
Male Pattern Baldness: classification and Incidence
A complete understanding of male pattern baldness is essential for consistently good results with hair transplantation, and its use in determining the incidence in 1,000 white adult male subjects is reported.
African hair growth parameters
Background Hair growth parameters have been studied mostly in caucasian hair, whereas few data on African hair have been reported in the literature.