Vellus Hairs on the Scalp

Does One Find Vellus Hairs Normally?

Vellus hairs are tiny, short non-pigmented hairs. They are fine hairs with a caliber less than 30 micrometers by definition. It is not common to find vellus hairs on the scalp in an individual without hair loss. On a normal scalp only about 1 of every 25 hairs are vellus hairs. Most hairs on the scalp are large pigmented terminal hairs. During the course of male and female androgenetic alopecia, vellus hairs become more prevalent and may even become the dominant hair type (outnumbering terminal hairs) in advanced balding cases.

Reference

Ko JH et al. Hair counts from normal scalp biopsy in Taiwan. Dermatol Surg. 2012