Variations of Hair Follicle Size and Distribution in Different Body Sites

The study examined hair follicle size and distribution in seven body sites of six healthy volunteers, revealing significant variations. The forehead had the highest follicle density (292 follicles/cm²) and smallest orifice diameters (66 μm), while the calf had the largest orifice diameters but lowest density (14 follicles/cm²). The forehead and calf also had the highest follicular infundibula volumes, indicating potential as reservoirs for topical substances. These findings underscored the importance of considering regional differences in hair follicle characteristics for optimizing drug and cosmetic formulations.