Aging is not fixed—it is dynamic, and perhaps even reversible. A groundbreaking 2025 study in primates has shown that cells engineered to resist senescence can slow, and possibly reverse, biological aging. In this essay, Dr. Don Howard explores how these modified progenitor cells may restore the body’s own repair capacity through biochemical communication rather than replacement. The findings, while early, challenge long-held assumptions about what it means to grow old—and invite a deeper reflection on the future of medicine as the stewardship of vitality.