Where Aging Begins: Inside the Mitochondria
The mitochondrial theory of aging suggests that mitochondria slowly accumulate damage—especially in their mitochondrial DNA (mtDNA)—because they produce both cellular energy and reactive oxygen species. As mtDNA mutations and deletions increase over time, some cells, particularly long‑lived ones like muscle and neurons, end up with dysfunctional mitochondria that weaken energy production and contribute to age‑related decline. Newer ideas, such as the “survival of the slowest” hypothesis, propose that damaged mitochondria persist not because they replicate faster, but because they are cleared more slowly. Although mtDNA mutations clearly rise with age and can harm cell function, the article notes that it’s still unclear how much they drive overall aging, highlighting the need for better tools and more research.
https://karger.com/nsg/article-abstract/10/3-4/162/334939/The-Mitochondrial-Theory-of-Aging
