Claim · 1925 · Voronoff testicular xenograft (chimpanzee-to-human)
Recipients of Voronoff's testicular xenograft experience meaningful extension of lifespan as a consequence of restored hormonal and cellular function.
The lifespan-extension claim follows from Voronoff’s underlying theoretical position that endocrine senescence is the primary driver of biological aging, and that restoring endocrine function via xenograft therefore restores lifespan. The empirical record disconfirms the claim: treated patients died at ages consistent with the contemporaneous life expectancy of their demographic stratum; no controlled comparison or longitudinal mortality assessment was ever conducted. The endocrine premise underlying the claim was itself displaced as endocrinology developed during the 1920s and 1930s.
Appears in
Sources
- Étude sur la vieillesse et le rajeunissement par la greffe — Voronoff, Serge. *Étude sur la vieillesse et le rajeunissement par la greffe*. Paris: Octave Doin & Gaston Doin, 1926. (Slug 'voronoff-life-and-work-of-monkeys-1928' preserved as the assigned identifier; the canonical Voronoff monograph during the practice's peak is the 1926 French *Étude* and the 1925 English *Rejuvenation by Grafting*. Voronoff's earlier 1920 *Life: A Study of the Means of Restoring Vital Energy and Prolonging Life* (Allen & Unwin) provides additional context.)