Intestinal aging and dietary nutrition strategies: focusing on autophagy

Intestinal aging is a progressive physiological process that accompanies organismal aging, characterized by a gradual decline in digestive, immune, and metabolic functions, thereby increasing the risk of age-related diseases. Despite advances in understanding, the underlying mechanisms of intestinal aging remain incompletely elucidated, with a major challenge being the lack of recognized biomarkers for accurately assessing its progression. Autophagy, a critical intracellular degradation and recycling pathway for maintaining intestinal homeostasis, declines with age. Restoring or enhancing autophagic activity may help delay aging; however, conflicting findings have emerged regarding its exact role in intestinal aging, underscoring the need for further mechanistic investigations. This review systematically summarizes the characteristic alterations and potential biomarkers associated with intestinal aging and proposes new insights into its relationship with autophagy. Moreover, aging-targeted interventions centered on the intestine hold promise for mitigating metabolic dysregulation and pathological changes during aging, thus contributing to healthy lifespan extension. Particular emphasis is placed on therapeutic strategies that modulate autophagy as a means to delay intestinal aging.