ABSTRACT
OBJECTIVE: A preliminary study was conducted in 17 female volunteers (mean age 29.8 years) to gain deeper insights into the characteristics of terminal Caucasian female body hair of different body parts. The focus on Caucasian women was driven by the high number of different scalp hair phenotypes in this ethnicity and intended to identify relevant differences between body areas to improve body hair removal approaches. METHODS: Multiple growth parameters and structural parameters were assessed for hair on the upper arm, forearm, upper leg, lower leg, axilla and intimate area and compared to scalp data. RESULTS: In particular, macroscopic and much less microscopic or hair surface properties differ strikingly in the investigated body areas. Hair density on the body is much lower than on scalp with the highest hair density in the axilla and intimate area. Multihair follicular units are described for scalp but were also found to a smaller proportion in the axilla and the intimate area. Substantial percentages of hair triplets are only found on the scalp and intimate area. Hair diameter is highest in the intimate area, followed by axillary and lower leg hair and correlates with a faster hair growth rate. The angle of emerging hair is smallest in the intimate area, axilla and on the lower leg. Hair shafts on the lower leg and in the axilla have most overlapping cuticle layers, but independent of body region, no significant differences in the mean thickness of cuticle layers were detectable. In addition, no differences were found in the mean distance between cuticle layer edges along the hair shaft and the hair surface roughness. Hair on the scalp, forearm, upper arm and upper leg had an almost round shape, whereas hair of the lower leg, intimate area and axilla had more elliptical shape. Hairs on the arm showed the highest luminance values and no visible medulla. The darkest hairs were in the axilla and intimate area containing the highest level of visible medulla in hair shafts. CONCLUSION: To our knowledge, this is the first systematic study comparing terminal hair properties in all cosmetically relevant body regions in Caucasian women.
