Berry et al. have recently published an article on Optogenetic rejuvenation of mitochondrial membrane potential extends C. elegans lifespan demonstrating mitochondrial control over the aging process in the nematode worm model. Their findings show that optogenetically increasing mitochondrial membrane potential during adulthood using a light-activated proton pump improves age-associated phenotypes and extends lifespan in Caenorhabditis elegans. The article also provides direct causal evidence that rescuing the age-related decline in mitochondrial membrane potential is sufficient to slow the rate of aging and extend healthspan and lifespan.