You Cannot Go Bald Without First Losing Your Hair: Telogen Effluvium as a Precursor to Common Baldness in Men

The study investigates the relationship between telogen effluvium (TE) and androgenetic alopecia (AGA) in men, focusing on whether TE precedes or follows AGA. Conducted on healthy males aged 18-55 with varying stages of balding, the research used phototrichograms to track hair changes over time. Results show a linear correlation between fibre diameter and anagen duration, with thin fibres having a shorter anagen duration of 200 days. In balding scalps, even thick anagen fibres have a reduced duration of 580 days. The study concludes that anagen shortening, indicative of TE, occurs before fibre diameter reduction, which is associated with AGA. This suggests that TE is a precursor to AGA, and shedding may not always be observed, especially in men with short hair. A new model for understanding the pathogenesis of balding is proposed.