Why we age
The dream of cheating death has evolved into a scientific quest to extend healthy life span. Scientists and doctors are looking for ways to maximize the number of years that we live free of chronic diseases, cancer, and cognitive decline. But before we can intervene, we have to understand the cellular and molecular mechanisms that drive aging and senescence. Some clues reside in our telomeres, the tips of our chromosomes that shrink with age. Others lie in our stem cells, which can only go on for so long repairing our tissues. Our mitochondria, too, the so-called powerhouses of the cell, may hold some answers to prolonging youthfulness. Other research points to changes in the gut microbiota associated with frailty in the aged. At a mechanistic level, the modulation of coenzyme NAD+ usage or production can prolong both health span and life span. Current geroscience initiatives aim to harness basic insights in aging research to promote general advances in healthy aging.