African hair growth parameters
Version of Record online: 23 DEC 2001
British Journal of Dermatology
Volume 145, Issue 2, pages 294–297, August 2001
How to Cite
Loussouarn, G. (2001), African hair growth parameters. British Journal of Dermatology, 145: 294–297. doi: 10.1046/j.1365-2133.2001.04350.x
- Issue online: 23 DEC 2001
- Version of Record online: 23 DEC 2001
- Accepted for publication 5 April 2001
- African hair;
- hair cycle;
- hair rate of growth;
- scalp hair density
Background Hair growth parameters have been studied mostly in caucasian hair, whereas few data on African hair have been reported in the literature.
Objectives To evaluate hair growth characteristics of African volunteers born in Africa.
Methods Thirty-eight young adults (19 women, 19 men, mean ± SD age 27 ± 10 years), native of central and western Africa, took part in the study. Phototrichograms were performed in order to record three parameters of hair growth: hair density, telogen percentage and rate of growth. For each volunteer, three regions of the scalp, namely vertex, temporal and occipital areas, were assessed.
Results Hair density varied from 90 to 290 hairs cm−2, with higher counts on the vertex. No significant difference between men and women was recorded. Telogen percentage showed wide variations, from 2 to 46%, with higher levels on the temporal area and in men. The rate of growth fluctuated from 150 to 363 µm day−1 with no difference related either to gender or to scalp region. These data were compared with those previously obtained in caucasian volunteers of comparable age, and showed significant differences between the two ethnic groups in all three parameters studied. Hair density in African volunteers was lower than that in caucasians (mean ± SD 190 ± 40 and 227 ± 55 hairs cm−2, respectively). African hair grew at a much slower rate than caucasian hair (mean ± SD 256 ± 44 vs. 396 ± 55 µm day−1), and telogen counts were frequently higher in African hair (mean ± SD 18 ± 9% vs. 14 ± 11%).
Conclusions This study demonstrated significant differences between African and caucasian hair growth parameters, which might suggest a trend towards increased hair loss in Africans, even though it contrasts with a lower and slower incidence of the development of alopecia in Africans.