What do free radicals have to do with aging?

Dr. Andrea Pennington, MD
Integrative Medicine
Normal cellular function results in the formation of highly reactive, terribly destructive particles known as free radicals. Free radicals are unstable molecules that have lost an electron in the process of metabolism. Free radicals cause damage by stealing electrons from cells in nearly every tissue in the body. This damage can speed up the aging process, make it more difficult to fight off infection, lower defenses against heart disease, and damage DNA, which can lead to cancer. The environmental factors that stimulate free radical production in our bodies include: UV rays, chemical radiation, cigarette smoke, automobile exhaust and pesticides, to name a few. We also cause free radical damage by not getting enough rest or sleep, not managing our stress responses, being inactive, and not eating healthfully.

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.