New 2026 research shows human aging is asynchronous. Your organs don't age at the same rate. A single "biological age" number misses the point.
If you've had a biological age test in the last five years, you got a single number. Maybe your chronological age is 52 but your "biological age" came back as 46, and you felt good about it. Or it came back as 58 and you felt less good about it.
The good news: you paid attention to your health.
The bad news: that one number is a blunt instrument, and science has moved past it.
A 2026 review in Ageing Research Reviews from Li and colleagues makes the case plainly: human aging is asynchronous. Your cardiovascular system can be aging at one rate, your kidneys at another, your brain at a third. The pattern of aging across organs — not the whole-body average — is what actually predicts mortality and disease.
The authors call this "organ ageing asynchrony," and the implications for preventive medicine are significant.
"Population-scale studies demonstrate substantial within-individual variation in organ-ageing rates, showing that accelerated ageing in specific organs and increased numbers of aged organs markedly contribute to systemic dysregulation and elevated mortality risk."
Under the old model — one epigenetic clock, one number — a patient with mildly accelerated cardiovascular aging, moderately accelerated renal aging, and dramatically accelerated brain aging might appear "average" on a single test. Their individual organ risks would be masked in the average.
Under the new organ-specific model — multiple clocks, multi-organ clocks, multi-omics integration — that patient's brain aging would show up as the highest-priority intervention target. The other systems would still be monitored, but clinical attention would concentrate where it matters most.
This isn't science fiction. The second-generation epigenetic clocks (GrimAge, DunedinPACE, PhenoAge) already stratify aging by different health outcomes. Third-generation clocks — currently being deployed in research settings — measure organ-specific aging trajectories directly. Proteomic clocks, including those detecting brain aging via serum and CSF protein signatures, are entering clinical use now.
Three reasons:
1. Organ crosstalk matters more than any single organ. Li and colleagues highlight cardiovascular–pulmonary–cerebral interactions as a major determinant of healthspan. Aging isn't isolated system by system — the systems influence each other. A decline in one accelerates decline in others. Understanding these networks requires measurements in multiple organs, not one composite score.
2. The interventions are different by organ. A patient with accelerated cardiovascular aging benefits from very different strategies than a patient with accelerated neurological aging. Exercise, statins, and ApoB targeting for one. Sleep architecture, cognitive load management, and specific nutrient targeting for the other. The right intervention depends on where the aging is concentrated.
3. Risk is non-linear. The paper notes that mortality risk rises sharply with the number of aged organs, not just the overall average age. A person with three accelerated-aging organs is substantially more at risk than one with one — even if their "average" biological age is the same.
Durand's executive health assessment doesn't give you a single biological age number. It gives you:
This isn't about being fancier. It's about matching the measurement approach to the actual biology of aging — the biology that Li and colleagues, and dozens of other research groups, are now converging on.
If your current executive physical gives you one biological age number, you're not getting the picture. You're getting a snapshot averaged across systems that age differently, driven by different causes, requiring different interventions.
The science has moved on. The clinics should too.
Research references in this article are sourced via PubMed.