Most of what we know about mitochondrial-targeted peptides comes from in vitro cell studies and in vivo animal experiments, not from real human beings. The few human trials that exist are short-term safety studies, often lasting only 7- 28 days, and they tell us nothing about what happens to mitochondrial membrane potential, redox signalling, fission–fusion dynamics, or mitophagy over months or years of use. There are no long-term human outcome trials, no multi-system follow-ups, and no data sho