Human Growth and Development / Unit 15 HGD 2105 short lesson, about 20 seconds
Free Radical Theory
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The idea
Free radical theory holds that unstable oxygen molecules, by-products of metabolism, take electrons from nearby molecules and damage cells cumulatively, a chain reaction across the cell.
In practice
Free radicals linked to disorders of advanced age, including cancer, atherosclerosis, cataracts and neurodegeneration.
Where people slip
Evidence for the theory is mixed, and research on antioxidant supplements remains inconclusive.
Your place on the trail
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