Challenging some widely accepted views: [phys.org]

[en.wikipedia.org]

"Damage occurs when the free radical encounters another molecule and seeks to find another electron to pair its unpaired electron. The free radical often pulls an electron off a neighboring molecule, causing the affected molecule to become a free radical itself. The new free radical can then pull an electron off the next molecule, and a chemical chain reaction of radical production occurs.[21] The free radicals produced in such reactions often terminate by removing an electron from a molecule which becomes changed or cannot function without it, especially in biology. Such an event causes damage to the molecule, and thus to the cell that contains it (since the molecule often becomes dysfunctional).

The chain reaction caused by free radicals can lead to cross-linking of atomic structures. In cases where the free radical-induced chain reaction involves base pair molecules in a strand of DNA, the DNA can become cross-linked.[22]

DNA cross-linking can in turn lead to various effects of aging, especially cancer.[23] Other cross-linking can occur between fat and protein molecules, which leads to wrinkles.[24] Free radicals can oxidize LDL, and this is a key event in the formation of plaque in arteries, leading to heart disease and stroke.[25] These are examples of how the free-radical theory of aging has been used to neatly "explain" the origin of many chronic diseases.[26]"