Who proposed the free-radical theory of aging?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

primates — aging Primates are among the longest-lived groups of mammals.

The free-radical theory of aging was first proposed in the 1950s by American gerontologist Denham Harman.1

This theory suggests that free radicals—atoms or molecules containing a single unpaired electron—cause oxidative damage to cellular components, such as membranes, as they accumulate over time. The theory specifically highlights the role of reactive oxygen species in this process. It has since been expanded to include the role of mitochondria, which are the primary sites of energy production in eukaryotic cells, where oxidative stress can lead to mitochondrial DNA mutations and impaired cellular function.1