Segmental Hair Analysis as a Retrospective Testosterone Diary: Possibilities and Pitfalls

September 2023 in “ Scientific reports ”

Julia K. Preinbergs, Jakob O. Ström, Elvar Theodorsson, Edvin Ingberg

testosterone segmental hair analysis hair growth rates biological sex natural hair color

TLDR Segmental hair analysis can track testosterone over time but needs adjustments for sex, hair color, and washing frequency.

This study investigated the stability of testosterone concentrations in hair over time to determine if segmental hair analysis can serve as a retrospective testosterone diary. Involving 30 men and 40 women, the study found a degree of segmental hormone conservation (rho = 0.405-0.461, p < 0.001, n = 66-67) but identified three confounders: higher testosterone in distal hair segments, the impact of frequent hair washing, and variability in hair growth rates. Biological sex, natural hair color, and relationship status significantly influenced hair testosterone levels. The findings suggest that repeated sampling near hair roots is preferable and adjustments for sex and hair color are necessary for accurate analysis.

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