Modern wearables can track everything from heart rate variability to sleep staging — but only a fraction have been clinically validated.
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For those aiming to optimize their health, the fundamental advice remains: maintain a balanced diet, engage in regular exercise, get enough sleep, and manage stress. But what specific health metrics should be monitored over time to truly gauge improvements in well-being? As of 2026, the tools for tracking health and wellness have become more advanced and accessible than ever.
Collecting health data is often an initial step towards better health outcomes. For many individuals, it turns vague wellness ambitions into actionable measures. This data offers a feedback loop that shows how the body reacts to stress, dietary changes, and physical activity, potentially identifying negative trends before they escalate into major health problems.
As a physician deeply involved in the latest health and wellness innovations, I offer insights into various methods of tracking health and aging, backed by scientific evidence.
Blood Biomarker Panels
Routine blood testing is a cornerstone of preventive healthcare. Such screenings typically begin around the age of 20, with most adults advised to have regular baseline checks, including CBC and cholesterol tests, during annual physical exams.
For those interested in longevity, more comprehensive blood tests are available, assessing apolipoprotein B (ApoB), high-sensitivity C-reactive protein (hsCRP), fasting insulin, and hormonal levels. These markers have strong longitudinal connections to mortality.
ApoB, in particular, is strongly supported by evidence. The 2026 ACC/AHA Dyslipidemia Guidelines recommend measuring ApoB as it more accurately predicts ASCVD risk than LDL-C, especially in individuals with diabetes or triglycerides ≥150 mg/dL. For hsCRP, a study highlighted that a single measurement could better indicate cardiovascular risk over 30 years than LDL cholesterol or lipoprotein(a).
Blood tests obtained through a doctor usually require a copay and vary with insurance plans. Alternatively, companies like Function Health ($365) and InsideTracker ($489 for a blood test & annual membership) provide panels with 50–250+ markers, enabling extensive testing without a doctor’s prescription.
While extensive multi-lab panels can detect health issues early and give valuable insights, interpreting the data can be challenging. More data isn’t necessarily better, and overtesting might lead to unnecessary worry and interventions.
Wearable Devices: The Always-On Health Monitor
Devices such as the Oura Ring ($349-499 with a $6/month subscription), Apple Watch ($249 for the SE to $799+ for the Apple Watch Ultra3), and WHOOP ($199 to $359 annually) continuously track metrics like heart rate variability, resting heart rate, sleep stages, activity levels, and increasingly, blood oxygen and skin temperature.
Consumer wearables are highly effective at monitoring heart rate or detecting conditions such as atrial fibrillation. However, they often overestimate total sleep time and show high variability in measuring physical activity intensity. Interestingly, only around 11% of commercially available devices are validated for at least one biometric outcome.
Despite these limitations, wearables are genuinely beneficial for tracking personal health trends over time.
VO₂ Max
VO₂ max, which measures the maximum oxygen uptake during exercise, is considered a powerful indicator of longevity. The American Heart Association recognizes cardiorespiratory fitness as a “clinical vital sign,” noting that each 1-MET increase is linked to a 10–25% improvement in survival.
The advantage of VO₂ max is that it can be improved at any age. The downside is that accurate measurement requires a formal cardiopulmonary exercise test (CPET). Sports clinics offer these tests for $400 to $600 out of pocket. Consumer wearables estimate VO₂ max from heart rate data, which is not perfect but reasonably aligns with measured values and is useful for monitoring trends over time.
Continuous Glucose Monitoring
Initially designed for diabetes, continuous glucose monitors (CGMs) are small sensors worn on the arm that measure blood sugar every few minutes. Recently embraced by the longevity community, brands like Dexcom’s Stelo ($99 for 30 days) and Abbott’s Lingo ($89 for 4 weeks) have popularized this technology. The concept is compelling: track how your blood glucose responds to food, exercise, stress, and sleep in real time.
However, evidence in non-diabetic adults is still emerging. A 2026 systematic review of 23 studies (1,074 non-diabetic participants) showed that CGM use significantly improved mean blood glucose compared to controls, primarily benefiting individuals with prediabetes. No significant glycemic improvement was noted in healthy normoglycemic individuals, nor was there a notable effect on body mass index (BMI).
Ultimately, CGMs serve as “precision biofeedback tools” integrated within structured lifestyle programs rather than standalone interventions. They provide valuable personalized data for individuals with prediabetes or strong family histories of type 2 diabetes, but their clinical utility for healthy individuals remains unproven.
DEXA Scans
The DEXA scan provides precise data on body composition, detailing muscle, fat, and bone distribution. This is significant because sarcopenia (muscle loss) and osteoporosis are hidden threats to healthspan, contributing to falls, fractures, and disability. Visceral fat (around organs) poses a greater cardiovascular and metabolic risk than body weight alone.
The evidence supporting DEXA is strong. The Health, Aging, and Body Composition Study revealed that both lower baseline levels and greater declines in DXA-measured lean mass, along with grip strength and gait speed, were linked to increased mortality over 10–14 years. Costing $75–150 and recommended annually after age 40, it is one of the most cost-effective tests available.
Epigenetic Age Clocks
Epigenetic clocks examine DNA methylation patterns to estimate biological age, which reflects how old your biology appears compared to your chronological age. Third-generation clocks like GrimAge and DunedinPACE show strong correlations with mortality across large groups.
A study of Finnish twins over 20 years confirmed that GrimAge predicted mortality independently of physical activity, BMI, smoking, and chronic diseases. DunedinPACE is particularly noteworthy, as it measures your current aging pace — one DunedinPACE unit equals one biological year per calendar year — and adds predictive value beyond GrimAge.
Saliva-based tests ($229 to $299) from companies like TruDiagnostic and Elysium make this technology accessible to consumers. However, substantial differences exist across clocks, with no single model being universally superior. These are best used as directional tools, repeated every 6–12 months, rather than definitive diagnostics.
Physical Performance Testing
Simple tests like grip strength, gait speed, and sit-to-stand repetitions may not seem cutting-edge, but the evidence linking them to longevity is remarkable — and they are essentially free.
A meta-analysis of 38 studies involving nearly 2 million participants found that higher grip strength was associated with a 31% lower risk of all-cause mortality, with a slightly stronger link in women.
Gait speed below 0.8 m/s in older adults is a strong independent predictor of adverse outcomes. The five-times sit-to-stand test evaluates functional lower extremity strength and is linked to fall risk and mortality. These can be tracked monthly at home with a $30 hand dynamometer and a stopwatch.
Sleep Tracking
Sleep is a crucial yet often overlooked factor in longevity. A UK Biobank study of over 407,000 individuals indicated that sleeping ≤5 hours was linked to a 25% higher all-cause mortality compared to sleeping 7 hours.
Sleep tracking involves more than just total hours: the proportion of deep sleep, REM sleep, efficiency, and consistency in timing all matter. Modern wearables provide reasonably accurate sleep staging, though they tend to overestimate total sleep time. A caution: tracking sleep can cause anxiety — a phenomenon called orthosomnia — which can ironically worsen sleep quality.
Proteomic and Multi-Omics Aging and Disease Clocks
High-throughput proteomic platforms like SomaLogic’s SomaScan can measure over 10,000 proteins at once, creating “aging clocks” that predict biological age and disease risk. A proteomic clock developed in the UK Biobank using nearly 3,000 plasma proteins achieved high accuracy in predicting chronological age and was linked to 18 major chronic diseases and all-cause mortality across diverse populations. Yet, comparisons suggest proteomic clocks perform similarly to epigenetic clocks, each capturing different aging dimensions.
The most promising approach may be multi-omics integration, combining proteomics, metabolomics, and epigenetics, achieving prediction accuracy exceeding 0.90 for conditions like type 2 diabetes and Alzheimer’s disease. Several companies are advancing these platforms for consumer accessibility, though costs remain high ($500–2,000+) and the commercial landscape is mostly outside peer-reviewed validation.
Despite their scientific promise, most molecular biomarkers of biological age are in early stages of translation. For most people, evidence doesn’t yet support routine use.
Full-Body MRI Screening
Whole-body MRI ($1,000–3,000) from companies like Prenuvo and Ezra offers early detection of cancer and organ disease. A 2026 systematic review of over 9,000 asymptomatic individuals found a pooled cancer detection rate of just 1.57%, with approximately 32% of scans revealing incidental findings requiring follow-up — most of which are benign.
Major medical organizations have not supported routine use in asymptomatic individuals, though for those with strong family histories or known genetic mutations (e.g., BRCA, Li-Fraumeni), the risk-benefit balance is more favorable. For the average healthy adult under 50, the value is probably not sufficient.
With a multitude of choices, it’s beneficial to prioritize tests based on evidence quality and cost, rather than novelty. Physical performance testing (grip strength, gait speed) and DEXA scans provide the strongest evidence relative to cost and should be part of most people’s routine. Including ApoB and hsCRP panels in standard bloodwork is advisable.
Wearables and CGMs are genuinely useful for monitoring personal trends. In contrast, epigenetic clocks, proteomics, and full-body MRI show promise but are still ahead of the evidence for most healthy adults — practical if cost isn’t a concern, but not essential. As in preventive medicine, consistently tracking a few well-validated metrics over years is more beneficial than pursuing every new test on the market.
