7 OCTOBER 2026 · LEE C. STONEHOUSE
How to Read Your Biological Age Results: Turning Blood Markers Into a Healthspan Plan
7 October 2026 · Lee C. Stonehouse
If you have more wealth than health, chronological age is a poor progress report.
It tells you how many birthdays have passed. It does not tell you how well you move, recover, regulate blood sugar, maintain muscle or manage the physiological effects of stress.
That is where a biological age test can add useful context.
Biological age is an estimate based on measurable characteristics of the body. Depending on the model, those characteristics may include blood markers, body composition, cardiovascular fitness, vital signs, DNA methylation or other biological signals.
The result is not a prophecy. It is a measurement.
Used correctly, it can help an over-40 reader move from vague concern to a structured healthspan plan: measure, intervene, track and repeat.
BIOLOGICAL AGE 101
What does a biological age test actually measure?
A biological age test does not measure one single thing called "age".
It combines selected data points into a model. The model then compares the pattern in those data points with patterns associated with people of different chronological ages.
Some research models use DNA methylation. Others use routine blood markers, physiological measurements, physical performance or combinations of several data types.
The scientific literature does not recognise one universal biological age test as the definitive gold standard. Reviews such as "Biological Age Predictors" in EBioMedicine and "Functional, Molecular, and Digital Measurements of Biological Age" in the Journal of Clinical Investigation describe a field that includes several different approaches.
That distinction matters.
A biological age result is only meaningful when the reader understands:
- Which markers were measured.
- Which laboratory or assessment method was used.
- How the data were weighted.
- Whether the test can be repeated consistently.
- What the result is designed to track.
A number without that context is decoration.
A number connected to repeatable measurements can become a management tool for healthspan.
THE SIGNALS THAT MATTER
What are the blood markers of longevity?
There is no single blood marker that can summarise the entire aging process.
However, research-based biological age models may include markers connected with several broad systems:
- Blood sugar regulation, including glucose or HbA1c.
- Kidney function, including creatinine.
- Liver and metabolic function.
- Inflammation-related markers.
- Blood-cell counts and immune characteristics.
- Lipids and cardiovascular risk factors.
- Albumin and other measures of general physiological status.
The specific markers, laboratory methods and mathematical weighting determine what a result means.
The 2018 study "An epigenetic biomarker of aging for lifespan and healthspan" by Levine and colleagues developed PhenoAge, a model based on clinical biomarkers and mortality-related outcomes. The research is important because it demonstrates how multiple biological signals can be combined rather than relying on one isolated result.
Other research has examined circulating blood biomarkers and composite biological age models, including the paper "Biological Age Estimation using Circulating Blood Biomarkers" in Nature Communications.
These studies support a measured approach, not a simplistic one.
Blood markers can be influenced by recent illness, medication, hydration, training load and other short-term factors. That is why one result should not be treated as a complete diagnosis or a fixed identity.
It is a data point inside a wider healthspan picture.
TEST THE METHOD, NOT JUST THE NUMBER
Read the result in context
An online biological age calculator can be a useful introduction, but it is not the same as an assessment built from measured biological data.
The key question is not whether a test produces an impressive number. The key question is whether the result can guide a sensible next step and be repeated under comparable conditions.
A useful assessment should make it easier to answer:
- Which area requires attention first?
- Which changes are realistic to implement?
- Which outcome will be tracked?
- When will progress be reviewed?
- What happens if the result does not improve?
Readers should also look at how a longevity clinic measures and repeats its assessments.
This is the difference between information and an operating method.
The AFT Bio Age model is a programme tracking model built around 12 markers across four domains. It brings together selected blood markers, body composition, fitness and vital signs. The result is intended to track change within the programme.
It is not an epigenetic clock, a clinical diagnosis, a prognosis, a lifespan predictor or a life-expectancy model.
That clarity is essential. Healthspan work becomes more credible when the limits of the measurement are stated plainly.
HOW TO READ YOUR RESULT
A lower bio age is not the entire objective
Many people see a biological age result and immediately focus on whether the number is above or below chronological age.
That is understandable. It is also incomplete.
The wider objective is improved capability.
A useful healthspan assessment should connect the composite result with the underlying components. A person may have a favourable overall bio age while needing to improve strength, aerobic fitness, sleep consistency or body composition. Another person may have a reasonable fitness level but unfavourable metabolic or cardiovascular markers.
The composite number provides direction. The component measures provide the work list.
After receiving a result, organise the information into three categories:
1. Preserve
Identify what is already working.
This may include regular resistance training, stable body weight, good sleep duration, strong cardiovascular fitness or consistent nutrition. Preservation matters because improvement often begins by protecting existing strengths.
2. Intervene
Identify the two or three measures most likely to respond to deliberate change.
The intervention may involve nutrition, exercise, stress control, recovery, sleep or professional medical support where appropriate. The programme should be specific enough to track and practical enough to repeat.
3. Verify
Set a review point.
The purpose of retesting is not to chase a flattering number. It is to examine whether the intervention produced a measurable change and whether the change can be maintained.
This is how a biological age test becomes useful after 40.
FROM RESULT TO ROUTINE
Build a healthspan plan around the ten tenets
A biological age result is a starting line, not a complete programme.
Lee C. Stonehouse built the 10-Tenet system to connect measurement with daily behaviour. The tenets cover attitude, nutrition, exercise, sleep, stress control, hormones and genetics, self-care, love and community, consistency, and cosmetic presentation.
The framework recognises a basic reality: biological performance is influenced by more than one habit.
A person can train hard and sleep poorly. Eat well and remain sedentary. Track blood markers while ignoring strength and mobility. Follow a perfect weekday routine and then abandon it every weekend.
The system is designed to reduce that fragmentation.
Each tenet gives the biological age result somewhere practical to go.
1. Attitude. A result only becomes useful when the reader decides to act on it. Attitude shapes whether the number is treated as feedback, not fate. It supports compliance, honest self-assessment and the willingness to repeat the process without drama.
2. Nutrition. Food choices influence glucose regulation, lipids, body composition and energy balance. Better nutrition can support improvements in several markers that commonly sit inside biological age models.
3. Exercise. Strength work, aerobic training and regular movement affect fitness, body composition, insulin sensitivity and functional capacity. If a biological age score is pointing toward low capability, exercise is often one of the most direct intervention tools.
4. Sleep. Poor sleep can undermine recovery, appetite regulation, stress response and training quality. A person who ignores sleep may struggle to move the very markers they are trying to improve elsewhere.
5. Stress control. Chronic stress can affect behaviour, recovery and physiological regulation. Stress control matters because a plan that looks good on paper can fail in practice if the nervous system is constantly overloaded.
6. Hormones and genetics. This tenet recognises that some readers need professional medical context, not guesswork. Family history, symptoms and relevant clinical assessment may help explain why progress is slower in one domain than another.
7. Self-care. This includes the practical maintenance work people often neglect when life gets busy: recovery habits, mobility, appointments, check-ins and the discipline to look after small issues before they become larger ones.
8. Love and community. Social environment shapes behaviour more than people like to admit. Support, accountability and the quality of close relationships can all influence whether healthy routines are sustained long enough to change measurable outcomes.
9. Consistency. This is where most plans either work or fail. Biological age does not move because of one excellent week. It moves when useful behaviours are repeated long enough for the markers to respond.
10. Cosmetic presentation. Appearance is not the same as health, but it can reinforce adherence. When people look sharper, stand taller and feel more physically capable, they often protect the behaviours that produced the shift.
For an over-40 reader, a practical first cycle might look like this:
- Establish the baseline. Record the relevant laboratory, fitness, body-composition and vital-sign data.
- Choose priorities. Select the most important modifiable weaknesses rather than changing everything at once.
- Match them to the tenets. Use the tenets to organise the work so each weakness has a clear behavioural home.
- Track adherence. Record whether the intended behaviour happened, not merely whether motivation was present.
- Repeat the assessment. Compare the new data with the baseline and adjust the plan.
The process is deliberately unglamorous.
It works through repetition.
LEE C. STONEHOUSE'S EXPERIENCE
Lee C. Stonehouse became a personal trainer at 21 in California after competing as a bodybuilder.
He describes having had more wealth than health before he began his own turnaround in 2015.
He subsequently wrote The Healthspan Extension Manual and built the 10-Tenet system he practises.
His own biological age assessment produced a biological age of 47 against a chronological age of 63.
That result is part of his personal measured experience. It is not a promise that every reader will produce the same outcome. It demonstrates the principle behind the method: assess the current position, apply deliberate interventions, and verify the response with data.
Readers can explore the healthspan manual and 10-Tenet framework, review the AFT Bio Age model, or examine the age-reversal programmes.
WHAT TO DO NEXT
Use the result as a decision tool
A biological age result should lead to better questions.
If the bio age is higher than chronological age, the response should not be panic. It should be investigation.
Which markers contributed to the result? Which factors are modifiable? Are the measurements reliable and repeatable? Could recent illness, medication, unusual training or another temporary factor have influenced the result?
If the bio age is lower than chronological age, the response should not be complacency.
Which behaviours are producing the result? Are they sustainable? Is physical capability being preserved alongside favourable laboratory data? What would protect the outcome over the next decade?
The aim is not to become obsessed with a single number.
The aim is to remain strong, capable and independent for longer.
That is the practical meaning of healthspan.
FAQ
What is a biological age test?
A biological age test estimates how an individual's measured biological characteristics compare with age-related patterns. Depending on the method, it may use blood markers, body composition, fitness, vital signs, DNA methylation or other data. The result is a modelled estimate, not a diagnosis or guaranteed prediction of lifespan.
Is a biological age calculator accurate?
An online biological age calculator can provide a broad lifestyle estimate, particularly when it uses self-reported information. However, it does not necessarily measure laboratory biomarkers directly. Its value depends on the questions, assumptions and validation behind it. It should be treated as an educational prompt, not a definitive health assessment.
What blood markers are used in biological age testing?
Different models use different combinations. Common categories include blood sugar regulation, kidney function, liver and metabolic markers, inflammation-related measures, lipids, albumin and blood-cell characteristics. There is no universal panel. The laboratory method, data quality and model weighting determine how the result should be interpreted.
Can biological age be reversed after 40?
Some biological measures are modifiable through changes in exercise, nutrition, sleep, stress control, body composition and recovery. In practical reverse aging work, that means establishing a baseline, applying targeted interventions and repeating relevant measurements to assess whether biological performance has changed. However, no test can guarantee a specific result for an individual.
Where can someone discuss a biological age assessment in Brighton?
People within a 10 mile radius of Brighton & Hove city centre can start a conversation with Lee through WhatsApp. Voice notes, text messages and voice calls are welcome via WhatsApp Lee. The discussion can cover the assessment process, healthspan priorities and whether a structured programme is appropriate.
THE NEXT MEASUREMENT
Chronological age will continue to move forward.
The more useful question is whether capability, recovery and biological performance are moving in the same direction.
A biological age test cannot do the work for anyone. It can, however, show where the work begins.
Measure the current position. Intervene with discipline. Track the response. Repeat the process.
Passive decline is not the only available plan.
Ready to understand what your healthspan data are telling you? Start a WhatsApp conversation with Lee using a voice note, text or voice call.