This study compared the effects of beta-hydroxybutyrate and NMN supplementation against caloric restriction in *Daphnia* (aquatic organisms), finding that beta-hydroxybutyrate supplementation replicated caloric restriction’s effect on reducing early mortality, while NMN supplementation did not produce similar benefits (animal model). The research suggests differential efficacy between these two proposed longevity interventions in this model organism, though findings in *Daphnia* may not directly translate to human physiology (animal model evidence level).