A high-fiber diet mimics aging-related signatures of caloric restriction in mammals

Caloric restriction (CR) delays aging-related hallmarks in various organisms by slowing growth and development while enhancing metabolic homeostasis. However, desirable diets that harness the metabolic benefits of CR without imposing food intake restrictions remain elusive. Here we evaluated the effects of a high-fiber diet we developed, in which 30% of the macronutrients in a standard diet are replaced with indigestible cellulose, compared to a CR control consisting of a nighttime-2h-restricted feeding regimen. Our findings show that the 2h-restricted feeding triggered a robust systemic response associated with the anti-aging benefits typically observed with CR. Intriguingly, the high-fiber diet did not reduce food intake but mimicked the aging-related signatures of CR in male mice from young to old age. These results indicate that the high-fiber diet confers promising benefits for metabolic homeostasis and represents a valuable candidate for further health and aging studies. Caloric restriction promotes healthy aging, but dietary alternatives are needed. Here, the authors show that a high-fiber diet mimics caloric restriction’s benefits in mice, improving metabolism, cognition, and aging markers without reducing food intake.