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Denham Harman
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Denham Harman

American gerontologist
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Denham Harman was an American gerontologist who proposed the free radical theory of aging in the 1950s. This theory suggests that aging is caused by the accumulation of damage from reactive molecules, known as free radicals, produced during normal cellular activities like cellular respiration. These free radicals, particularly reactive oxygen species (ROS), can damage cellular components such as membranes. Harman's work indicated that antioxidant proteins, which neutralize free radicals, become more abundant in aging cells, suggesting a response to this oxidative stress. His theory was later expanded to include the role of mitochondria in producing ROS and contributing to cellular dysfunction and degeneration over time.1

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3 Britannica Sources
  1. aging - Oxidative damage theory
  2. gerontology and geriatrics
  3. harman

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