FixMyAge
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The Science

Built on decades of aging research

Our methodology combines three pillars of biological age measurement — epigenetic clocks, blood biomarker analysis, and physical performance testing — each backed by rigorous science.

Epigenetic Clocks

DNA methylation patterns change predictably with age. Epigenetic clocks measure these patterns to estimate biological age with remarkable accuracy.

2013

Horvath Clock

The original multi-tissue epigenetic clock. Analyzes 353 CpG sites to estimate biological age across diverse tissue types.

2019

GrimAge

Predicts time-to-death and lifespan. Incorporates smoking pack-years and plasma protein surrogates for superior mortality prediction.

2022

DunedinPACE

Measures the pace of aging — how fast you're aging right now. Designed from longitudinal data tracking organ-system decline over time.

Evidence Tiers

Not all interventions have the same level of evidence. We classify every protocol recommendation into three tiers so you know exactly what you're getting.

Tier 1Strong Evidence

Multiple RCTs, meta-analyses, or large cohort studies support the intervention. These form the backbone of our protocols.

Regular aerobic + resistance exerciseMediterranean-style dietary patternsSleep optimization (7-9 hours)Omega-3 fatty acid supplementation
Tier 2Moderate Evidence

Supported by smaller RCTs, strong observational data, or compelling mechanistic evidence. Included with appropriate context.

NMN / NR supplementationVitamin D optimizationTime-restricted eatingCold exposure protocols
Tier 3Emerging Evidence

Early-stage research with promising signals but limited human data. Flagged as experimental in our protocols.

Rapamycin (off-label, clinical supervision only)Senolytics (dasatinib + quercetin)Epigenetic reprogramming factorsHyperbaric oxygen therapy

Key References

The foundational research that informs our methodology.

  1. [1]Horvath S.DNA methylation age of human tissues and cell types. Genome Biology, 2013;14(10):R115
  2. [2]Lu AT, Quach A, Wilson JG, et al.DNA methylation GrimAge strongly predicts lifespan and healthspan. Aging (Albany NY), 2019;11(2):303-327
  3. [3]Belsky DW, Caspi A, Corcoran DL, et al.DunedinPACE, a DNA methylation biomarker of the pace of aging. eLife, 2022;11:e73420
  4. [4]Fitzgerald KN, Hodges R, Hanes D, et al.Potential reversal of epigenetic age using a diet and lifestyle intervention. Aging (Albany NY), 2021;13(7):9419-9432
  5. [5]Levine ME, Lu AT, Quach A, et al.An epigenetic biomarker of aging for lifespan and healthspan. Aging (Albany NY), 2018;10(4):573-591

See the science in action

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