• Intestinal immunosenescence involves immune cell dysfunction, disrupted immune-microbiota interactions, and impaired barrier function, contributing to age-related diseases.
• Aging-induced gut microbiota alterations compromise mucosal integrity and immune regulation, creating a vicious cycle of declining immunity.
• Dietary interventions, microecological therapy, and fecal microbiota transplantation show promise in restoring immune function and reducing inflammation in the elderly.
• Precision interventions targeting intestinal immunosenescence could improve healthspan and quality of life in the aging population.