Abstract
Hair may vary considerably in length, width, quantity, and distribution of follicles depending on its type and location on the human body. The two main types of hair are terminal hair and vellus hair. Terminal hairs are normally thicker and longer, with hair shaft diameters greater than 0.06 mm and hair bulbs rooted deeply in the subcutaneous tissue. On the other hand, vellus hairs are usually only 1–2 mm in length and have thinner shafts measuring less than 0.03 mm in diameter. Their bulbs are located in the upper portion of the dermis, and they are characteristically more hypopigmented than the baseline hair color. Vellus hair is typically more noticeable on women and children because men tend to have more terminal body hair [1].
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Tung, J.K., Yasuda, M.R. (2020). Anatomy and Physiology of the Hair Cycle. In: Lee, L.N. (eds) Hair Transplant Surgery and Platelet Rich Plasma. Springer, Cham. https://doi.org/10.1007/978-3-030-54648-9_1
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