June 19th, 2026
Producing new aging clocks is easier than overcoming the hurdles to the practical use of existing aging clocks, so the research community is generating new clocks at a fair pace while failing to make much concrete progress on the challenging problem of how to use clocks to assess novel potential rejuvenation therapies. An aging clock measures some combination of parameters that at least appears to reflect biological age. Given that clocks are reverse engineered from epidemiological data via machine learning techniques and the research community has not established clear links between biological age and any of the specific parameters used in a clock, it is entirely unclear as to whether any given clock will accurately reflect the outcome of an actual rejuvenation therapy. Will it understate or overstate the effects of repairing some form of cell and tissue damage? Will its predictions regarding mortality risk turn out to be correct? They only way to find out at present is qualify a specific clock for a specific intervention via the slow and expensive life span studies that everyone wants to avoid. Some way to fix this present situation is needed, and building more clocks seems unlikely to achieve that goal.
