Chronic inflammation and the biological aging clock are more intertwined than we thought
Two of the most discussed phenomena in aging research — chronic low-grade inflammation and the biological clock of cells — are more tightly linked than previously understood.
Biological age is not the same as chronological age. Cells and tissues can look molecularly older than your birth year would suggest — or younger. Biological age is measured using so-called epigenetic clocks: methods that look at chemical tags on DNA that shift as a person grows older. Alongside this sits inflammaging — the gradual accumulation of chronic, low-grade inflammation that characterises the aging body and is linked to dementia, cardiovascular disease, diabetes, and cancer.
What the new study, published in Cell Genomics, adds is a mechanistic insight: inflammaging doesn’t merely accompany epigenetic aging — it appears to actively drive it. Researchers analysed the relationship between inflammatory markers in the blood and the readouts of four different epigenetic clocks in a large population. The correlations were robust: higher inflammation levels were associated with accelerated biological age, independently of other factors.
What’s the mechanism?
The causal relationship has not yet been definitively proven — correlation in population studies is not proof of cause and effect. But the biological plausibility is strong. Inflammatory signals can directly influence epigenetic marks: they activate enzymes that add or remove methyl groups from DNA, precisely the changes that clocks like GrimAge and PhenoAge register. At the same time, epigenetically aged cells may themselves secrete more inflammatory molecules, creating a self-reinforcing cycle.
That mechanism matters because it suggests where interventions might have traction. If you can dampen inflammaging — through diet, exercise, or targeted drugs like NLRP3 inhibitors currently in clinical trials — that could theoretically slow the biological clock as well. The reverse is also conceivable: interventions that roll back epigenetic age, such as reprogramming protocols tested in animal models, might reduce inflammaging as a side effect.
Measuring is not the same as understanding
A caveat: epigenetic clocks measure something real, but exactly what remains debated. They are calibrated on population data and predict statistical risk, but they are not a perfect mirror of how old an individual cell is functionally. The same uncertainty applies to inflammaging: chronic inflammation is not a single phenomenon but a complex of overlapping immune processes. That the two systems are linked is a valuable finding — but translating that into concrete, measurable interventions requires considerably more work.