Limitations of Ageing Biomarkers

Tissue Specificity

Different organs and tissues can age at different rates. Many widely used biomarkers are derived from blood or plasma and may not capture ageing processes in the brain, muscle, or other non-hematopoietic tissues, limiting their organ-specific interpretability. [1] [2]

Short-Term Variability

Many biomarkers fluctuate with sleep, stress, diet, or acute illness. Without repeated measurements, it can be difficult to separate signal from noise, especially for inflammatory and metabolic markers with substantial within-person variability. [2] [3]

Model Dependence

Biomarker algorithms are trained on specific datasets. When applied to new populations, they may be less accurate due to differences in age range, ethnicity, health status, or technical protocols. This limits generalizability across cohorts and complicates cross-study comparability. [4] [5]

Clinical Validity

A biomarker can correlate with ageing without being clinically actionable. Evidence that changing the biomarker improves health outcomes is often limited, and few biomarkers have validated thresholds that guide treatment decisions or predict intervention benefit. [6] [7]

Summary

Ageing biomarkers are informative but imperfect. Their limitations include tissue specificity, measurement variability, model transferability, and uncertain clinical impact. [2] [5] [6]

References

1. Moqri, M., et al. (2024). Validation of biomarkers of aging. GeroScience. https://pmc.ncbi.nlm.nih.gov/articles/PMC11090477/
2. Horvath, S., & Raj, K. (2018). DNA methylation-based biomarkers and the epigenetic clock theory of ageing. Nature Reviews Genetics, 19(6), 371-384. https://onlinelibrary.wiley.com/doi/abs/10.1002/mef2.50
3. Zhang, C., Zhu, P., et al. (2023). Biomarkers of aging. Signal Transduction and Targeted Therapy, 8(1), 144. https://pmc.ncbi.nlm.nih.gov/articles/PMC10115486/
4. Moqri, M., et al. (2024). Generalizability and cohort effects in biomarker models of aging. GeroScience. https://pmc.ncbi.nlm.nih.gov/articles/PMC12262637/
5. Martin-Ruiz, C., et al. (2014). Biomarkers of healthy ageing: expectations and validation. Proceedings of the Nutrition Society. https://www.cambridge.org/core/journals/proceedings-of-the-nutrition-society/article/biomarkers-of-healthy-ageing-expectations-and-validation/5710EA381976F548980F7A3EA54FC09C
6. Perri, R., et al. (2025). Expert consensus statement on biomarkers of aging for use in clinical trials. The Journals of Gerontology: Biological Sciences. https://pmc.ncbi.nlm.nih.gov/articles/PMC11979094/
7. Herzog, C., et al. (2024). Challenges and recommendations for the translation of biomarkers of aging. Nature Aging. https://www.nature.com/articles/s43587-024-00683-3