Description
What is the Clock Foundation PhenoAge Test?
The Clock Foundation PhenoAge Test provides an estimate of your biological age using a panel of clinical blood biomarkers. These biomarkers reflect areas such as inflammation, metabolism, kidney function, liver and bone-related markers, red blood cell indices and immune cell profile.
The PhenoAge approach was developed from work by Dr Morgan Levine, Professor Steve Horvath and colleagues. It is designed to estimate biological ageing using measurable physiological markers rather than date of birth alone.
Click here to learn more about biological age.
What does biological age mean?
Your chronological age is your age in years from your date of birth. Your biological age is an estimate of how your body appears to be ageing based on measurable biological markers.
For example, two people may both be 50 years old chronologically, but their biological age estimates may differ depending on health, inflammation, metabolism, lifestyle, sleep, exercise, diet, smoking, alcohol, weight, stress and other factors.
A biological age test does not tell you exactly how long you will live. It provides a personalised marker that may help you understand whether your body appears biologically younger, similar to, or older than your chronological age.
What does the PhenoAge Test measure?
The Clock Foundation PhenoAge Test estimates biological age using a group of clinical blood biomarkers. These are combined mathematically to produce a biological age estimate.
The result gives an estimate of your biological age, sometimes described as your “body clock” age. This may be lower than, similar to, or higher than your actual chronological age.
The result should be interpreted as one part of a wider health picture rather than as a diagnosis on its own.
What biomarkers are used?
The PhenoAge calculation uses a group of clinical blood biomarkers. These include:
- Albumin – a protein made by the liver, influenced by nutrition, inflammation and general health
- Creatinine – a marker related to kidney function and muscle metabolism
- Glucose – a marker of blood sugar regulation and metabolic health
- C-reactive protein, or CRP – a marker of inflammation
- Lymphocyte percentage – part of the white blood cell profile, reflecting immune balance
- Mean cell volume, or MCV – a measure of average red blood cell size
- Red cell distribution width, or RDW – a measure of variation in red blood cell size
- Alkaline phosphatase, or ALP – an enzyme linked to liver, bile duct and bone activity
- White blood cell count – a general marker of immune and inflammatory activity
These markers are not interpreted in isolation. They are combined as part of the PhenoAge calculation and should be reviewed in clinical context.
Who is this test for?
This test may be suitable for adults who are interested in:
- understanding their biological age
- reviewing ageing and longevity markers
- monitoring health and lifestyle changes over time
- taking a more personalised approach to preventative health
- reviewing whether further health checks may be appropriate
It may be of particular interest to people who are already making, or planning to make, changes to diet, exercise, sleep, weight, alcohol intake, smoking status, stress management or general health.
This test is not intended to replace medical assessment, screening, blood tests or investigation of symptoms.
How the test works
The test is arranged through Innermost Healthcare. A blood sample is collected and sent to the laboratory for analysis.
The laboratory measures the relevant clinical biomarkers, and these are used to calculate a biological age estimate. Once the result is available, it can be reviewed in clinical context, taking into account your age, symptoms, medical history, family history, lifestyle and any other relevant health information.
We can discuss what the result means, what it does not mean, and whether any further health checks or lifestyle review may be appropriate.
Results and follow-up
Your report will provide an estimate of biological age. This may be useful as a baseline measurement, especially if you are planning health or lifestyle changes and may want to monitor change over time.
If your result suggests accelerated biological ageing, this does not mean that you have a specific medical condition. It may, however, be a useful prompt to review modifiable health factors and consider whether any further clinical assessment or blood testing is appropriate.
If your biological age appears lower than your chronological age, this should still be interpreted carefully. It is reassuring as a marker, but it does not exclude future health risks or replace recommended screening and medical care.
Important limitations
The Clock Foundation PhenoAge Test is a biological ageing test. It is not a diagnostic test for cancer, cardiovascular disease, dementia, fertility problems, hormone disorders or any other specific medical condition.
The result should not be interpreted in isolation. Biological ageing tests can provide useful information, but they are still only one part of a broader assessment of health and risk.
If you have symptoms, a known medical condition, a strong family history, or specific concerns about your health, you should arrange an appropriate medical consultation rather than relying on biological age testing alone.
Frequently asked questions
Is biological age the same as my actual age?
No. Your actual, or chronological, age is based on your date of birth. Biological age is an estimate of how your body appears to be ageing based on biological markers.
What is PhenoAge?
PhenoAge is a biological age estimate based on clinical blood biomarkers. It was developed to provide a measure of biological ageing using physiological markers rather than chronological age alone.
Is PhenoAge an epigenetic test?
No. The PhenoAge test described here is based on clinical blood biomarkers, not DNA methylation. Some research uses the term DNAm PhenoAge, which refers to a related DNA methylation-based epigenetic measure, but this Clock Foundation PhenoAge Test is a blood-biomarker test.
What is the difference between PhenoAge and GrimAge?
PhenoAge is based on clinical blood biomarkers, including markers related to inflammation, metabolism, kidney function, liver and bone activity, red blood cell indices and immune profile.
GrimAge is an epigenetic ageing test based on DNA methylation markers. It is designed to provide a broader epigenetic biological ageing assessment and is included in the Clock Foundation Epigenetic Age Test.
Neither test diagnoses a specific disease. The most appropriate test depends on whether you want a blood-biomarker estimate of biological age or a more detailed epigenetic ageing assessment.
Can biological age be improved?
Potentially, yes. Biological ageing may be influenced by factors such as smoking, alcohol, sleep, exercise, diet, weight, inflammation and underlying health conditions. The result may help guide a broader health review.
Does this test diagnose disease?
No. This test does not diagnose a specific disease. It should be viewed as a health and longevity marker rather than a diagnostic medical test.
Can this test predict how long I will live?
No. The test does not predict lifespan for an individual person. It provides an estimate of biological age, which may be useful as part of a wider health and longevity assessment.
Should I repeat the test?
Some people repeat biological age testing after lifestyle or health interventions, but this should be considered on an individual basis. A repeat test may be useful if you want to monitor change over time.
Do I still need routine health screening?
Yes. Biological age testing does not replace routine health screening, medical reviews, blood tests or investigation of symptoms. It should be used alongside appropriate medical care.
