Lipid peroxidation is initiated by reactive molecules like hydroxyl radicals interacting with unsaturated lipids, forming damaging lipid peroxides.

“here's an unsaturated lipid right here that looks a lot like something that you could see on maybe a molecule like linoleic acid or icosapentanoic acid and it has a double bond and if the double bond comes into contact with a hydroxyl radical you get this lipid radical the lipid radical undergoes propagation and you get this lipid peroxyl radical and you get a lipid peroxide this is exactly what i showed you guys in the previous the previous uh slide you have an r group which is the whole molecule here and the ooh this is a hydroperoxide a lipid peroxide it is a very reactive molecule it can do this lipid peroxidation reaction this is what we don't want to happen”