7. Lifespan Interventions Can Differ in Effect between Males and Females

Many longevity interventions act by rebalancing organism-wide allocation (growth/reproduction versus maintenance/repair) and by reshaping endocrine, immune, and metabolic setpoints, which may be different in males and females. In the deleteriome framework, this means the starting composition of burden, the dominant weak links, and the architecture that maps burden to mortality risk can differ by sex; therefore, the same perturbation can lower risk in one sex (e.g., by relieving its limiting bottleneck) yet yield smaller benefit, or introduce offsetting tradeoffs, in the other. Sex also modulates exposure and response: pharmacokinetics, tissue distribution, and target engagement can differ, and so can the downstream adaptive programs (stress responses, autophagy, inflammation, remodeling). Practically, sex offers a systems-level context: an intervention’s effect size reflects i) which deleteriome components it shifts, ii) which organs are limiting in that sex, and iii) whether the net change reduces long-term burden rather than merely exchanging one burden for another.