Most people guess their "biological age" based on how they feel. That's not how this works.

After tracking 200+ anti-aging protocols and reviewing the latest longevity research, here are the 5 biomarkers that actually matter:

1. Telomere Length

The caps on your chromosomes literally shorten with age. But certain lifestyle interventions (meditation, omega-3s, exercise) have been shown to slow or even reverse this. You can test this with a simple blood kit.

2. Glycan Age

Glycans are sugar molecules attached to your proteins. Your GlycanAge score is one of the most accurate predictors of biological aging — and it responds fast to lifestyle changes. Some people drop 5+ years in 6 months.

3. DNA Methylation (Epigenetic Clocks)

Tests like TruAge and Horvath's clock measure actual cellular aging. This is the gold standard. If you're only going to track one thing, track this.

4. VO2 Max

Your cardiovascular fitness is the single strongest predictor of all-cause mortality. A high VO2 max at 40 means you're biologically closer to 25. Train zone 2 cardio 3-4x per week.

5. Fasting Insulin / HOMA-IR

Insulin resistance accelerates every aging pathway. Keep fasting insulin under 5 μIU/mL and you're in elite territory. Intermittent fasting, strength training, and cutting refined carbs are your weapons.

The problem? Nobody tracks these consistently. That's exactly why I built YouthStack — a system to log your biomarkers, protocols, and habits so you can see what's actually working.

If you're serious about reverse aging, stop guessing and start measuring.