by Claire Richardson, November 2025
If you are somewhere between 40 and 65, you are part of the first generation in history to have hard numbers on how fast you are ageing, not just how old you are.
For most of human history, age has been a simple count of birthdays. The new science of epigenetic and “multi-system” ageing changes that. It suggests that your body carries a detailed record of the wear and tear of your life so far: in your DNA methylation patterns, in the way different organ systems drift out of sync, and in the number of years you are likely to spend in what geriatricians call ‘late-life morbidity’, the years when health problems crowd out the freedom to live as you wish.
Put differently, roughly one in every four to five years of life is now lived with significant health limitations. The question is whether emerging ageing science can help us compress that period and move disability and dependency later, into a shorter final chapter, while keeping the middle decades as vital as possible.
As the health scientist behind Second Prime® at GHS Clinics, I want to unpack what this science actually means for an individual in midlife trying to stay well, and where the line currently lies between robust evidence and speculative promise.
From birthdays to biological age
The starting point is epigenetics. Epigenetic marks are tiny chemical tags attached to DNA that help control which genes are switched on or off. They change in response to development, environment and lifestyle. In 2013, Steve Horvath published the first widely used “epigenetic clock”, a mathematical model that uses DNA methylation patterns at a set of sites across the genome to estimate biological age across multiple tissues with striking accuracy.
Subsequent work has refined this idea. Newer clocks do not just estimate age; they track the pace at which someone is ageing. The DunedinPACE algorithm, for example, uses repeated measures from a New Zealand birth cohort to create a blood-based measure of how fast multiple organ systems are deteriorating over time, and links this to later morbidity, disability and mortality.
These tools are not yet ready to drive individual clinical decision-making, and a recent major review in Cell emphasised that biomarkers of ageing, including epigenetic clocks, still lack agreed standards for clinical use. But the direction of travel is clear. Biological age is no longer a metaphor. It is something we can measure, imperfectly but meaningfully, and, crucially, something that appears to move in response to what we do.
Biological age is best thought of as a risk signal, not a verdict.
For a 52-year-old business owner in Cheltenham or Charlton Kings, the message is not that a test will “tell your future”, but that we can increasingly quantify whether your current lifestyle and physiology are likely to give you more healthy years, or fewer.
Multi-system ageing: when the orchestra drifts out of tune
Chronological age rises at the same speed for everyone. Biological ageing does not.
One of the most important insights of the last decade is that ageing is best understood as multi-system dysregulation where several physiological systems slowly drift out of their optimal range together.
Alan Cohen and colleagues showed this elegantly by developing a statistical index that combines multiple blood biomarkers into a single measure of physiological dysregulation. As people age, this index rises, reflecting the fact that small deviations across many systems, such as; inflammation, lipids, glucose control, kidney function and so on, collectively predict frailty and mortality better than any single marker. Thomas Kraft extended this approach in a Tsimane population, showing that multi-system dysregulation increased with age even in a subsistence setting, demonstrating that this is a general property of human ageing, not just a Western lifestyle phenomenon.
Think of your body as an orchestra rather than a single instrument. Ageing is what happens when more and more sections slip slightly out of tune, and the overall sound deteriorates long before any one instrument breaks.
In practice, this means that an individual might have near-ideal cholesterol but rising inflammatory markers and a subtle decline in kidney function; or excellent cardiorespiratory fitness but early signs of sarcopenia and disturbed sleep. Looking at one system in isolation misses the pattern.
At GHS Clinics, this multi-system view is built into the Second Prime® model. We are less interested in whether any one number is marginally “out of range” and more interested in how clusters of biomarkers, symptoms and lived experience line up across key ageing domains; metabolic and movement, cognitive load, immune and gut-brain signalling, neuroendocrine balance.
The real signal in midlife is not a single bad test, but the quiet accumulation of small drifts across systems.
What the intervention science is starting to show
The next question is whether this multi-system and epigenetic picture is merely descriptive, or whether we can meaningfully influence it.
On the experimental side, Richard Miller’s laboratory at the University of Michigan has been central in demonstrating that ageing can be delayed in mammals. Through the NIA Interventions Testing Program, Miller and colleagues have shown that the drug rapamycin, started in middle-aged, genetically diverse mice, can extend median lifespan by around 10% in males and 18% in females, and increase maximum lifespan as well. These effects are accompanied by delays in multiple age-related diseases and functional decline, suggesting a deceleration of ageing itself rather than simply preventing one cause of death.
Miller has long argued that the goal of such interventions is not to produce a world of very old, very frail people, but to extend healthy life and compress morbidity so serious disease and disability are moved closer to the end of life, into a shorter final period.
In humans, we cannot yet give you a rapamycin-like drug in clinic specifically “to slow ageing”. The safety and ethics are still being worked through, and no regulator has approved such an indication. But the animal data matter because they show, beyond reasonable doubt, that ageing biology is modifiable.
Closer to home, Janet Lord’s group at the University of Birmingham has been instrumental in characterising inflammageing, which is the chronic, low-grade inflammation that accompanies ageing, and exploring how lifestyle and targeted interventions can influence immune ageing. In 2024, Lord and colleagues reported the results of a randomised trial in older adults where a multi-component nutritional supplement led to a modest but statistically significant reduction in epigenetic age in participants whose epigenetic clocks were initially “older” than their chronological age.
This is not a miracle pill. The changes in DNA methylation age were measured in months, not decades, and only in a subgroup with raised baseline epigenetic age. But it is an important proof-of-concept: in real people, not mice, we can influence biological ageing markers in a direction that plausibly aligns with better long-term health.
Taken together with trials of structured exercise, sleep interventions and cardiometabolic risk reduction that show slower accumulation of multi-system dysregulation and lower future disease burden, the message is clear.
Ageing is not a fixed trajectory; it is a process that can be sped up or slowed down, system by system.
Compression of morbidity: why “the last 20%” matters
The phrase “compression of morbidity” was coined by James Fries in 1980. He argued that if we can delay the onset of chronic disease and disability more than we extend overall lifespan, the period of life spent in poor health will shrink so it is compressed into a shorter interval at the very end. Later work, including actuarial analyses by Eric Stallard, has refined this idea, exploring how trends in disability, disease and mortality interact to produce real-world patterns of morbidity.
In contemporary England, we are not yet where Fries hoped we would be. Data compiled by the King’s Fund, drawing on the Office for National Statistics, show that for 2020–2022, men could expect to live 78.8 years on average, of which 62.4 years would be in good health, leaving 16.4 years (21%) in poor health. Women could expect to live 82.8 years, with 20.1 of those years (24%) in poor health.
For a reader in midlife, this is the uncomfortable baseline:
if you follow the average path, something like the last fifth of your life will be spent managing significant health problems.
Our aim with longevity-focused care is not to deny death or chase extreme lifespan, but to bend that curve so that more of your seventies and early eighties feel like an extension of midlife, and serious morbidity is delayed and shortened.
This is where the concept of multi-system ageing becomes practical. If we can identify and reduce dysregulation across systems in midlife, through strength and balance training, metabolic stabilisation, sleep and stress modulation, immune and inflammatory control, and targeted pharmacology where appropriate, we increase the odds that your personal morbidity curve is compressed, even if your total lifespan does not change dramatically.
What this means if you are trying to stay well in the Cotswolds
All of this can sound abstract until you bring it down to the level of a real life.
Imagine a 55-year-old client, living in Cheltenham, running a growing business, commuting, supporting teenage children and ageing parents. On paper, they are “fine”: no diagnosed disease, moderately active, a bit more tired than ten years ago. From a traditional healthcare standpoint, this is not someone who would trigger urgent concern.
From a multi-system ageing standpoint, the picture might look different. Blood panels reveal early insulin resistance, low-grade systemic inflammation and borderline low muscle mass. Epigenetic age, measured in a research context, is a few years older than chronological age. Sleep tracking shows fragmented sleep and short recovery windows. Our Second Prime® System reveals high cognitive and psychological load and low perceived recovery.
None of these signals alone constitutes a diagnosis. Together, they describe an accelerated pace of ageing, with multiple systems slightly off course. Left alone, this trajectory is exactly the sort that tends to convert into late-life morbidity in the statistics.
This is where Second Prime® is designed to operate. We start from the science, Horvath’s clocks, Cohen’s dysregulation indices, Miller’s work on decelerated ageing, Lord’s trials on ‘inflammageing’ and epigenetic modification, and translate it into an integrated, personalised strategy.
In practical terms, that might mean:
- Strength and balance work prescribed as if it were a drug, because we know it is one of the most potent levers for reducing future frailty and compression of morbidity.
- Metabolic and nutritional interventions aimed not just at weight, but at improving the underlying multi-system dysregulation score including stabilising glucose, lipids and inflammatory markers.
- Sleep and cognitive-load interventions targeted at the specific patterns revealed in the Second Prime® system, to protect cognitive resilience and neuroendocrine balance.
- Selective use of advanced biomarkers, including research-level ageing clocks where appropriate and clearly framed, to track whether the interventions are genuinely slowing the pace of biological ageing rather than just improving how someone feels this month.
The goal is not to chase a lower “biological age” score for its own sake. It is to stack the odds in favour of you spending more of the next 25 to 30 years in robust health, and less of them in that final fifth of life where morbidity tends to cluster.
What the science of epigenetic and multi-system ageing really offers is not a prediction of your fate, but a more precise map of where to intervene while there is still time.