Biomarkers of Ageing
This information is for educational purposes only. Mention of specific biomarkers does not constitute a recommendation for testing or diagnosis. Always consult a medical professional.
What is a Biomarker?
A biomarker (biological marker) is a measurable indicator of some biological state or condition. In the context of longevity research, a "biomarker of ageing" is a parameter that could theoretically predict functional capability at a later age better than chronological age alone.
Types of Biomarkers
Researchers categorize potential ageing biomarkers into several levels:
- Molecular: Markers found in DNA (e.g., DNA methylation patterns, often called "epigenetic clocks") or blood (e.g., inflammatory proteins).
- Physiological: Measures of organ function, such as cardiovascular capacity or kidney filtration rates.
- Functional: Physical tests like grip strength or walking speed, which are strongly correlated with overall health in older populations.
Research vs. Clinical Use
It is vital to distinguish between biomarkers used in research studies and those validated for clinical use.
- Research Tools: Many "biological age clocks" are powerful tools for studying population trends and testing interventions in clinical trials. However, their accuracy for a single individual is often debated.
- Clinical Diagnostics: Validated medical tests used by doctors to diagnose specific diseases. Most "biological age" tests sold directly to consumers are not diagnostic tools.
Limitations
There is currently no single "gold standard" biomarker for ageing. Different tissues may age at different rates, and environmental factors (stress, diet, time of day) can temporarily fluctuate many markers. Therefore, reliance on a single metric can be misleading.