The ionome is the elemental composition of a tissue, organ, or individual. This composition changes over the course of aging, and may do so in ways that allow the production of an aging clock, a measure of chronological or physiological age.
Image credit: Doalex via Wikimedia (CC BY-SA 4.0)
This line of development adds to work on the well-known epigenetic clocks, proteomic clocks, and other assessments of age constructed from algorithmic compositions of simple biomarkers.
At the end of the day, all of these approaches need a great deal more validation if they are to be used as originally intended, as a way to rapidly assess potential rejuvenation therapies and thus speed up the field. Since it remains quite unclear as to what exactly these clocks measure, meaning which processes of aging cause the clock numbers to change, the results are not yet actionable.
Link: https://doi.org/10.1111/acel.13119
Source: Fight Aging!