Chronic inflammation and biological aging are more deeply intertwined than we thought
Two of the most talked-about phenomena in aging research, chronic low-grade inflammation and the biological clock of cells, turn out to be far more entangled than previously assumed. A new study lays out for the first time in detail how they influence each other, and what that means for the search for interventions.
Biological aging is not the same as chronological age. At the molecular level, your cells and tissues can look older than your birth year would suggest, or younger. That biological age is measured using so-called epigenetic clocks: tools that look at chemical marks on DNA that shift as a person gets older. Alongside that sits the phenomenon of inflammaging, the gradual buildup of chronic, low-grade inflammation that characterizes the aging body and has been linked to dementia, cardiovascular disease, diabetes, and cancer.
What the new study, published in Cell Genomics, adds is a mechanistic insight: inflammaging does not simply walk in step with epigenetic aging, it appears to actively drive it. Researchers analyzed the relationship between inflammatory markers in the blood and the readouts of four different epigenetic clocks across a large population. The correlations were robust: higher levels of inflammation tracked with accelerated biological age, independent of other factors.
What is driving this?
A definitive causal link has not yet been established, as correlations in population studies do not prove cause and effect. But the biological plausibility is strong. Inflammatory signals can directly alter epigenetic marks: they switch on enzymes that add or remove methyl groups from DNA, precisely the changes that clocks such as GrimAge and PhenoAge detect. At the same time, epigenetically aged cells can themselves secrete more inflammatory molecules, creating a self-reinforcing cycle.
That mechanism matters because it points to where interventions might actually make a difference. If you can dial down inflammaging, through diet, exercise, or targeted drugs such as NLRP3 inhibitors currently being tested in clinical trials, you could in theory slow the biological clock as well. The reverse is equally plausible: interventions that wind back epigenetic age, like some reprogramming protocols in animal models, might reduce inflammaging as a side effect.
Measuring is not the same as understanding
One caveat is worth keeping in mind: epigenetic clocks measure something real, but exactly what remains a matter of debate. They are calibrated on population data and predict statistical risk, but they are not a perfect mirror of how old an individual cell is in functional terms. The same uncertainty applies to inflammaging: chronic inflammation is not a single phenomenon but a tangle of overlapping immune processes. The fact that the two systems are linked is a valuable finding, yet translating that into concrete, measurable interventions still requires a great deal of work.