By 20 months of age in mice, significant irreversible age-related damage like collagen cross-linking, neuronal death, and arterial clogging has likely begun.

“by the time you're 20 months of age in a mouse which is sort of like 55 or 60 years old in a person something like that not yet at the median survival but getting pretty close that's damage will have occurred that's irreversible collagen cross-linking and death of some brain cells and uh clogging of the arteries or whatever is going to get you”