Updated October 2026: corrected company and test descriptions, removed testing companies we could no longer verify, added current epigenetic clocks and the latest evidence on test reliability, and fixed broken links.
Abstract: Biological Age Tests
Biological age testing has gained significant attention as a tool for assessing an individual's physiological state and predicting health outcomes. Unlike chronological age, biological age aims to reflect how genetic, lifestyle and environmental factors have shaped a person's health status.
This article explores the main types of biological age testing offered by companies like TruDiagnostic, GlycanAge, Life Length and other diagnostic laboratories, highlighting their methodologies, applications and limitations for tracking biological age, health and longevity in clinical practice.
Clinics using Heads Up can bring biological age results into the longevity clinic platform alongside labs and wearables, so each patient's results sit in one longitudinal record. For a comparison of tools, see our guide to the best software for longevity practices.
Introduction to Biological Age Testing
Biological age is a measure of an individual's functional and physiological health, which can differ from chronological age, the time elapsed since birth. Various biological age testing methods have been developed to quantify this measure, offering insights into aging processes and health risks. These tests typically assess biomarkers that correlate with aging, such as DNA methylation, glycan patterns, telomere length and, increasingly, circulating proteins.
Biological Age Testing: Key Concepts and Importance
What is Biological Age?
Biological age refers to the biological state of an individual's body systems and tissues, influenced by genetics, lifestyle and environmental exposures. In large population studies, some biological age measures, such as the DNA methylation clocks PhenoAge and GrimAge, predict mortality and age-related disease better than chronological age alone. How well any single test predicts outcomes for an individual patient is less certain, as discussed below.
Importance of Biological Age Testing
Biological age testing can add context about the aging process and help identify areas for health improvement. In practice it is used to:
- Assess Health Risks: Flag patients who may be aging faster than expected and warrant closer follow-up.
- Monitor Longevity Interventions: Track changes over time alongside lifestyle and treatment changes.
- Personalize Health Strategies: Support conversations about individualized health and wellness plans.
Types of Biological Age Testing
1. DNA Methylation Testing
DNA methylation is an epigenetic modification that changes with age and is influenced by factors such as diet, stress and environmental exposures. Tests measuring DNA methylation estimate biological age by analyzing methylation patterns at specific sites (CpG sites) in the genome.
TruDiagnostic
Methodology: TruDiagnostic analyzes DNA methylation across hundreds of thousands of CpG sites using a genome-wide methylation array, then applies several algorithms, including pace-of-aging measures such as DunedinPACE and its own OMICmAge and SYMPHONYAge clocks. Heads Up offers a TruDiagnostic integration.
Applications: Used to assess aging processes, evaluate the impact of lifestyle changes on epigenetic age and support personalized health interventions.
Benefits: Provides a detailed epigenetic profile with multiple clocks from a single sample, including measures of the current pace of aging.
Limitations: The test requires a blood sample, and epigenetic measures change over months rather than days, so they are not suited to tracking short-term changes.
Epigenetic Clock Testing
Several companies offer DNA methylation-based biological age tests using various epigenetic clocks:
- Horvath Clock: Developed by Dr. Steve Horvath, it estimates age based on methylation levels at 353 CpG sites and works across many tissues and cell types. It is widely used in research.
- PhenoAge: A DNA methylation clock trained to predict "phenotypic age," a measure derived from routine clinical blood markers. It outperformed earlier clocks in predicting mortality, cancers, healthspan and physical functioning.
- GrimAge: A DNA methylation clock built to predict lifespan and healthspan, using methylation-based surrogates for plasma proteins and smoking history.
- DunedinPACE: Rather than an age in years, it estimates the current pace of aging, distilled from two decades of follow-up in the Dunedin birth cohort. It was designed to exclude probes with low test-retest reliability.
2. Glycan Age Testing
Glycans are complex carbohydrates attached to proteins and lipids, influencing various biological processes. The glycosylation of immunoglobulin G (IgG) changes with age and has been studied as a biomarker of both chronological and biological age.
GlycanAge
Methodology: GlycanAge measures the glycosylation patterns of IgG, which shift with age and with chronic inflammation. The test analyzes specific glycan structures to estimate biological age.
Applications: Used to monitor the impact of lifestyle changes on biological age, evaluate inflammation-related aging and guide personalized interventions.
Benefits: Offers a view of immune system and inflammatory aging from a finger-prick blood sample that patients can collect at home.
Limitations: The test focuses on glycan patterns, which may not fully capture all aspects of biological aging.
Glycan Research Laboratories
- Genos: A glycobiology laboratory in Zagreb, Croatia, led by Gordan Lauc, that developed the GlycanAge test. Its research on IgG glycans and aging underpins much of the published work in this area.
3. Telomere Length Testing
Telomeres are protective caps at the ends of chromosomes that shorten with cell division. Telomere length has long been studied as a biomarker of cellular aging. Read more in our post on telomeres and longevity.
Life Length
Methodology: Life Length, a CLIA- and ISO-certified laboratory, measures telomeres using its patented Telomere Analysis Technology (TAT), a high-throughput quantitative FISH method. Rather than reporting only an average, it reports the distribution of telomere lengths and the percentage of critically short telomeres.
Applications: Used to assess cellular aging, monitor the effects of interventions and support personalized health strategies.
Benefits: Provides a direct measure of telomere length at the single-cell level.
Limitations: Telomere length is influenced by many factors, including genetics and lifestyle, which can complicate interpretation.
Other Telomere Testing Companies
- RepeatDx: Specializes in telomere length analysis using Flow-FISH technology, which measures telomere length in specific white blood cell populations. Its clinical use is focused mainly on diagnosing telomere biology disorders such as dyskeratosis congenita and on pulmonary fibrosis.
- SpectraCell: Offers a telomere length blood test that practitioners can order alongside its other assessments. Heads Up offers a SpectraCell integration.
4. Metabolomic and Proteomic Testing
Metabolomic and proteomic tests analyze the profiles of metabolites and proteins in the blood, providing insights into metabolic and physiological changes associated with aging.
Emerging Research
- Proteomic aging clocks: In 2024, researchers used 2,897 plasma proteins measured in more than 45,000 UK Biobank participants to build a proteomic age clock from 204 proteins. Proteomic aging was associated with the incidence of 18 major chronic diseases, multimorbidity and all-cause mortality, and the clock performed similarly in cohorts from China and Finland.
- Commercial availability: Proteomic and metabolomic aging clocks remain largely research tools. Before ordering a commercial test in this category, ask the vendor which published, validated clock it uses.
Applications: These approaches are being studied to evaluate metabolic health, track the impact of dietary and lifestyle changes and estimate organ-specific aging.
Benefits: They may provide a broad view of physiological changes associated with aging.
Limitations: The interpretation of metabolomic and proteomic data is complex and requires advanced analytical tools and expertise.
5. Composite and Multi-System Biological Age Tests
Composite approaches combine multiple biomarkers or physiological systems to provide a broader assessment of biological age.
Elysium Health
Methodology: Elysium Health's Index test analyzes DNA methylation from a saliva sample to report an overall biological age plus nine system-level ages.
Applications: Used to monitor the impact of lifestyle changes on biological age and to highlight body systems that may be aging faster.
Benefits: Offers a system-by-system view of aging rather than a single number.
Limitations: System-level estimates add complexity, and interpretation requires an understanding of how each score was derived.
6. Other Companies and Services
Tally Health: Offers the TallyAge test, a cheek-swab DNA methylation test based on the CheekAge epigenetic clock. A company-funded study found CheekAge was predictive of mortality.
Zymo Research: Provides the DNAge epigenetic age analysis service, used mainly in research settings.
Practical Applications and Implications for Health and Longevity
Personalizing Health Strategies
Biological age testing can support personalized health strategies that address the specific needs and health risks of each patient. Results are most useful when interpreted alongside standard clinical markers; see our longevity biomarker panel guide and our companion post on biological age tests.
Monitoring Longevity Interventions
Repeat testing can help track changes in biological age over time alongside dietary changes, exercise programs and other interventions. To make repeat results comparable, use the same laboratory and the same clock each time, and avoid comparing numbers across vendors.
Validating Health Outcomes
For healthcare providers and researchers, biological age testing offers one way to assess the outcomes of health interventions. Interpret single-test changes with caution: one analysis found that technical noise alone produced differences of up to 9 years between replicate samples for six prominent epigenetic clocks, although newer principal-component versions of those clocks agreed within 1.5 years for most replicates.
Ethical and Practical Considerations
As of 2024, the Biomarkers of Aging Consortium reported that there is no consensus on how biomarkers of aging should be validated before clinical use. Practitioners should present results as estimates rather than diagnoses, avoid overstating what a change in score means, and consider data privacy and informed consent when using biological age testing in clinical and research settings.
Conclusion
Biological age testing is a promising but still-maturing tool for assessing health, monitoring aging processes and guiding personalized interventions. Companies like TruDiagnostic, GlycanAge, Life Length and others offer a range of options that use different biomarkers and technologies.
By integrating these tests thoughtfully into health and longevity programs, and tracking them alongside labs, wearables and functional measures, healthcare providers can better evaluate their strategies for maintaining patient health. As validation research matures, biological age testing is likely to play a growing role in longevity care.
References:
- Horvath, S. (2013). DNA methylation age of human tissues and cell types. Genome Biology, 14(10), R115. PubMed
- Belsky, D. W., et al. (2015). Quantification of biological aging in young adults. Proceedings of the National Academy of Sciences, 112(30), E4104. PubMed
- Levine, M. E., et al. (2018). An epigenetic biomarker of aging for lifespan and healthspan. Aging, 10(4), 573. PubMed
- Lu, A. T., et al. (2019). DNA methylation GrimAge strongly predicts lifespan and healthspan. Aging, 11(2), 303. PubMed
- Belsky, D. W., et al. (2022). DunedinPACE, a DNA methylation biomarker of the pace of aging. eLife, 11, e73420. PubMed
- Krištić, J., et al. (2014). Glycans are a novel biomarker of chronological and biological ages. Journals of Gerontology: Series A, 69(7), 779. PubMed
- Higgins-Chen, A. T., et al. (2022). A computational solution for bolstering reliability of epigenetic clocks. Nature Aging, 2(7), 644. PubMed
- Moqri, M., et al. (2024). Validation of biomarkers of aging. Nature Medicine, 30(2), 360. PubMed
- Argentieri, M. A., et al. (2024). Proteomic aging clock predicts mortality and risk of common age-related diseases in diverse populations. Nature Medicine, 30(9), 2450. PubMed
- Shokhirev, M. N., et al. (2024). CheekAge, a next-generation epigenetic buccal clock, is predictive of mortality in human blood. Frontiers in Aging, 5, 1460360. PubMed
Track Biological Age Alongside Everything Else
Heads Up unifies labs, wearables, medical devices and EHR data in one longitudinal patient record, extracts lab PDFs automatically, and gives you an AI copilot that summarizes what changed since the last visit. See how Heads Up tracks biological age and longevity outcomes for your clients: request a demo.
See how clinics use Heads Up
Unify labs, wearables and EHR data into one AI-assisted view. Book a walkthrough tailored to your practice.
