Biological Age
Definition
Biological age is an estimate of how old a person's body appears biologically, rather than how many years they have lived. It is used to describe physiological state relative to what is typical for a given chronological age, often by comparing biomarker patterns, functional measures, or composite models. [1] [3] [4]
Why It Matters in Ageing Research
The term matters because people of the same chronological age can differ substantially in function, disease risk, and biomarker patterns. Researchers use biological age models to study whether some people seem biologically older or younger than expected, but different models may capture different aspects of ageing rather than one single underlying truth. [2] [4] [7]
Common Confusion
- Biological age is not a hidden exact age waiting to be measured perfectly.
- Different biological age models are not interchangeable.
- A biological age estimate is not a diagnosis on its own.
Related Reading
References
- Hamczyk, M. R., et al. (2020). Biological versus chronological aging: A review. https://www.lidsen.com/journals/geriatrics/geriatrics-03-02-051
- Rollandi, G. A., et al. (2019). Biological age versus chronological age in the prevention of age-related diseases. https://www.lidsen.com/journals/geriatrics/geriatrics-03-02-051
- Salih, A., et al. (2023). Conceptual overview of biological age estimation. https://pmc.ncbi.nlm.nih.gov/articles/PMC10187689/
- Johnson, A. A., & Shokhirev, M. N. (2024). Contextualizing aging clocks and properly describing biological age. https://pmc.ncbi.nlm.nih.gov/articles/PMC11634725/
- Belsky, D. W., et al. (2022). Aging clocks & mortality timers: A window to measuring biological age. https://pubmed.ncbi.nlm.nih.gov/35783114/
This glossary entry is provided for educational purposes only and does not constitute medical advice.