Biological age tests compared: which ones are worth paying for?
TruAge, GlycanAge, Elysium Index, and more. What each measures, accuracy, and whether results are actionable.
The promise of biological age testing
Your chronological age is fixed. Your biological age, the functional state of your body’s systems, may not be. Biological age tests attempt to measure how fast you are aging relative to your birth date, and ideally to track whether interventions (exercise, diet, supplements) are working.
The market for these tests has exploded. Prices range from $99 to $499 per test. The question is whether the results are reliable enough to act on.
How epigenetic clocks work
Most biological age tests use DNA methylation patterns: chemical tags on your genome that change predictably with age. The original Horvath clock (2013) analyzed 353 methylation sites. Newer clocks use different site selections and algorithms to improve prediction of specific outcomes.
The key distinction is between clocks that predict chronological age (first generation) and clocks that predict mortality or disease risk (second and third generation). You want the latter.
The major tests
TruAge (TruDiagnostic): Uses the DunedinPACE algorithm, which measures pace of aging rather than a single age estimate. Currently considered the most actionable consumer test because it tracks rate of change.
GlycanAge: Measures glycan profiles on immunoglobulin G rather than DNA methylation. Glycans reflect immune and inflammatory aging. Different methodology, potentially complementary to epigenetic tests.
Elysium Index: Uses their proprietary algorithm on DNA methylation data. Reports biological age plus a “rate of aging” metric.
Are the results actionable?
This is the critical question. A test that says “your biological age is 45 when you are 40” is only useful if you can identify what to change and verify the change worked on retest.
Current evidence suggests that DunedinPACE responds to caloric restriction and exercise within months. This makes it the strongest candidate for tracking intervention effects. Single-point biological age estimates are less responsive to short-term changes and more prone to noise between tests.
Recommendation
If you are going to test, use DunedinPACE-based testing (TruAge), test at baseline, implement a specific intervention for 6 months, then retest. Comparing two data points is more useful than interpreting a single result.