Ahead of The Longevity Show, Steve Horvath explains why precision measurement is the first step in a preventative health revolution.

The Longevity Show returns with a program that reflects a field in transition – no longer content with abstract promises of lifespan extension, but increasingly focused on the practicalities of delivery, measurement and clinical integration. Day two of the Business Conference, framed around Engaging With the Future of Longevity, leans into this shift, bringing together clinicians, scientists and operators to explore how emerging tools and technologies are beginning to translate into real-world health optimization. It is a subtle but important recalibration; away from theory and toward implementation, where questions of evidence, scalability and standardization begin to carry more weight than ambition alone.

Among the sessions, The Science of Assessment places measurement firmly at the center of the longevity conversation – a theme that has gained traction as the field matures. Featuring Principal Investigator at Altos Labs, Dr Steve Horvath, alongside Phil Newman, Dr Raghib Ali and Dr Samantha Decombel, the discussion focuses on biomarkers, multi-omics and evidence-based testing as the foundation for personalized, longitudinal care. Horvath’s presence is particularly notable; as the architect of the epigenetic clock, his work has done more than perhaps any other to shift biological age from abstraction to quantifiable metric, bringing with it both opportunity and a degree of necessary scrutiny.

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Longevity.Technology: If longevity medicine is to move beyond well-intentioned optimization into something resembling a clinical discipline, it will need to answer a deceptively simple question: how do we measure it? Sessions such as this suggest the field is beginning to take that challenge seriously – not through any single biomarker or platform, but through a layered approach that combines molecular data, longitudinal tracking and increasingly sophisticated interpretation. Horvath’s contribution sits at the heart of that evolution; his epigenetic clocks have become both a tool and a loaded gauntlet, forcing the sector to confront what biological age actually represents and how confidently it can be acted upon. Around this, a broader ecosystem is emerging – multi-omics panels, AI-driven analytics, clinical protocols – each promising clarity, each introducing its own complexity. The risk, perhaps, is that measurement outpaces meaning, that data accumulates faster than consensus. Yet without such efforts, longevity remains descriptive rather than actionable. In that sense, the real significance of sessions like this lies not in any single insight, but in the attempt to build a coherent diagnostic framework – one capable of translating biological signals into decisions, interventions and, ultimately, outcomes that can be tracked over time. Leading up to The Longevity Show, we sat down with Dr Steve Horvath to discuss the biological reality of epigenetic timing and the necessity of clinical unity.

Riding more than the first wave

For all the proliferation of biological age clocks – and the inevitable confusion that has followed – Horvath is clear that the field is not as fragmented as it might appear. “We are not at consensus but we are at convergence,” he tells us, pointing to a gradual alignment around a smaller number of validated tools.

The early generation of clocks, trained against chronological age, served a purpose but were never designed with clinical translation in mind. “The first wave of clocks was trained against chronological age which is useful for certain applications but limited when it comes to human clinical trials,” he explains. More recent iterations – including PhenoAge and GrimAge – have shifted toward phenotypic and mortality-linked outcomes, while DunedinPACE attempts to quantify the rate at which an individual is aging.

This evolution is beginning to crystallise into something more structured. Horvath describes an emerging set of criteria that any clinically meaningful biomarker must meet: “it has to predict hard outcomes such as time to death or specific diseases, it has to move in response to interventions, and it has to replicate across populations.” The direction of travel is encouraging, even if the destination remains just out of reach. “We are much closer to that bar than we were five years ago but harmonization of assays and prospective interventional data are still works in progress. Almost there.”

The Longevity Show Business Conference is set to draw a global crowd, including researchers, clinicians, scientists, founders and investors A moment of alignment

If the science is converging, so too is the broader ecosystem around it – which, in Horvath’s view, helps explain why events like The Longevity Show are emerging with a more practical, translational focus.

“Several things have aligned,” he says. “The geroscience hypothesis, i.e. that targeting aging biology itself is a tractable strategy, is no longer fringe.” That shift has been accompanied by more tangible progress: surrogate endpoints that avoid the need for decades-long mortality studies, early human trials beginning to report results, and a growing influx of capital from both established players and newer longevity-focused ventures.

Then there is the demographic backdrop – impossible to ignore and increasingly difficult to defer. “Aging populations across most of the developed world,” Horvath notes, have turned longevity from an intellectual curiosity into something closer to a policy and economic imperative. “Slowing or reversing aging has arguably become an economic and medical priority not a niche curiosity.”

Still, he offers a note of restraint – or perhaps realism. “The honest counterweight is that there is a lot of wishful thinking as opposed to hard data,” he says, expressing a hope that forums like this can “help to separate signal from hype.”

The limits of precision

If measurement is becoming more sophisticated, it is also becoming more nuanced – and, in some respects, more complicated. The idea of a single, definitive biological age readout remains appealing, but Horvath is quick to challenge the premise.

“I think the premise needs a correction first: we cannot yet measure biological age with total precision,” he says. Nor, he suggests, is that ever likely to be possible through a single metric. “Biological age is multi-dimensional. The full picture comes from a basket of measurements.”

That basket is expansive; biochemical blood panels, methylation data, proteomics and metabolomics sit alongside imaging, wearable-derived data and functional assessments such as VO2 max, muscle strength and cognitive performance. Each captures a different facet of aging biology, and none can stand entirely alone.

The question of how individuals engage with this data is equally complex. For some, the act of measurement is inherently motivating. “Some people genuinely enjoy measurement. I am one of them,” Horvath admits. “I treat it as a hobby and it motivates me to maintain a healthy lifestyle.” Others, however, may find the same information overwhelming or anxiety-inducing. “Too much testing makes them anxious. I respect that.”

His advice, characteristically, lands somewhere in the middle. “There is a sensible middle ground. Get your blood pressure and standard vitals checked roughly once a year. Pay attention to the basics. But do not obsess unless you are a longevity athlete.” The deeper point, though, is less technical and more human. “Your happiness and purpose are not built out of test results. It’s built out of friendships, purpose, making time for fun, good sleep, and movement. Tests are a useful nudge at least to me but they are not the destination.”

Beyond the clock

For someone whose work helped define the field, Horvath is notably forward-looking about what comes next. The concept of a single, whole-body clock may ultimately give way to something far more granular.

“The most important [frontier] is moving from whole-body, blood-based clocks to clocks that accurately measure the biological age of individual organs and organ systems,” he says, pointing to the brain, kidney, lung, liver and heart as obvious candidates. Such resolution would allow clinicians to identify which systems are aging fastest within a given individual – and intervene before dysfunction becomes clinically apparent.

This, in turn, opens up a more fundamental question. “Can we find targeted interventions… that reverse damage or rejuvenate an organ before it fails?” If the answer is yes, the implications extend well beyond individual health. “We change the entire economics of medicine, because prevention is dramatically cheaper than treatment. A stitch in time saves nine.”

For researchers, the horizon stretches further still, toward increasingly fine-grained models of aging. Horvath points to “single cell aging clocks in different species” as another emerging area – a reminder that, even as the field edges closer to clinical application, its scientific foundations continue to evolve.

The Longevity Show – a festival of science, wellness & human potential
26 – 27 June 2026 | Tobacco Dock, London