The surprising new finding was that castration at 240 days of age (roughly equivalent to 30 years in humans), rather than just before or after puberty, extended median lifespan even further. Contrary to expectations, this suggests that testicular factors are beneficial early in life, with survival benefits persisting long after puberty, but become detrimental later in life. Of course the goal is not to castrate humans, the goal is to figure out what factor is causal, e.g. testosterone, which would have major implications and through what mechanisms so we can figure out the mystery behind the male longevity disadvantage and potentially remove it without having to castrate anyone. Very solid study! https://www.biorxiv.org/content/10.64898/2026.10.19.760267v1