A Hypothetical Pathogenesis Model for Androgenic Alopecia: Clarifying the Dihydrotestosterone Paradox and Rate-Limiting Recovery Factors

December 2017 in “ Medical Hypotheses ”

Robert S. English

androgenic alopecia dihydrotestosterone DHT hair follicle miniaturization tissue remodeling capillary network calcification sebaceous gland enlargement microvascular deficiency scalp tension androgens arterial calcification fibrosis transforming growth factor beta-1 TGF-ß1 AGA

Studysummary This review evaluates dihydrotestosterone's role in androgenic alopecia and proposes a model suggesting that chronic scalp tension and inflammation contribute to hair follicle miniaturization, identifying fibrosis, calcification, and tension as treatment targets.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

The 2018 document proposed a hypothetical model for the development of androgenic alopecia (AGA), a condition affecting a significant portion of men and women. The model suggested that chronic scalp tension could induce an inflammatory response, leading to an increase in dihydrotestosterone (DHT) levels in AGA-prone tissues. However, DHT was not directly linked to hair follicle miniaturization, but rather to tissue remodeling conditions that restrict follicle growth. The document also suggested a link between AGA progression and factors such as capillary network calcification, sebaceous gland enlargement, and microvascular deficiency. It highlighted a potential relationship between skull shape and baldness patterning and suggested that scalp tension could contribute to AGA hair thinning. The document also discussed the role of androgens in arterial calcification and fibrosis, and the potential role of transforming growth factor beta-1 (TGF-ß1) in AGA. Further research was needed to confirm these hypotheses.

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