What do free radicals have to do with aging?

When we're young, our cells have a defense system called superoxide dismutase (SOD) that reins in unstable molecules called free radicals, which wind through the body looking for electrons to snatch. The theory of aging is that as we get older, SOD doesn't work as well, reducing the body's defenses against free radicals. When they cause too much cellular damage, cells die. These molecules have been implicated in conditions that become more common with aging, including cancer, dementia and heart disease.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.