UNIQUE BIOLOGIC FEATURES OF AFRO-TEXTURED HAIR
Curved/ Curly hair and follicle in the scalp | Elliptical (Caucasians- oval &Asians round)
A high degree of irregularity in the diameter along the hair shaft, with frequent twists and random reversals in direction with pronounced flattening.
African hair tends to form knots
Lower stress required to break the hair
Earlier breaking time under a given force
Microcracks and fractures in the hair fiber caused by natural constrictions along the twisted hair shaft leading to lower tensile strength and relative brittleness. This is made worse by everyday combing and grooming
Least amount of cuticle layers leading to a higher prevalence of hair breakage
Fewer elastic fibers anchoring the hair follicles to the dermis in the black subjects, leading to an increased susceptibility to traction alopecia
SEBACEOUS (OIL) GLANDS:
Uneven distribution of sebum from root to tip resulting in dryer hair
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