The Biology of Hair Growth

January 2009 in “ Elsevier eBooks ”

Valerie A. Randall, Natalia V. Botchkareva

TLDR Hair growth is influenced by hormones and goes through different phases; androgens can both promote and inhibit hair growth depending on the body area.

The document from 2009 provides an extensive review of the biology of hair growth, detailing the hair growth cycle, the role of hormones in hair follicle function, and the paradoxical effects of androgens on hair growth. It explains that hair follicles are dynamic organs that go through phases of growth (anagen), regression (catagen), resting (telogen), and shedding (exogen). The document highlights the importance of the dermal papilla in hair growth and the influence of androgens, which can stimulate hair growth in some body areas while causing hair loss in others, such as in androgenetic alopecia. It also discusses the psychological impact of hair disorders and the significance of hair in human communication. The study of seasonal changes in hair growth involved 14 healthy Caucasian men aged 18-39 years over 18 months, showing significant seasonal behavior in hair growth patterns. The document emphasizes the need for further research into the factors altered by androgens to better understand follicular cell interactions and the pathogenesis of androgen-dependent hair disorders.

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7 / 7 results

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