The Blood Markers Longevity Experts Track, and How to Check Yours
Peter Attia, Andrew Huberman, Bryan Johnson, Casey Means and other longevity-focused physicians and researchers publish the markers they follow and, for most, a target number. Every target here is attributed to the person who cited it, from a podcast, book, or interview. These are expert protocols, not FixFirst clinical claims.
What this section covers
A standard lab reference range is built from the middle 95% of a general population. It tells you whether a result is common, not whether it is optimal for a specific longevity goal.
The people in this section publish narrower targets than a lab report uses, on their own podcasts, in their books, and in interviews. FixFirst did not invent these numbers. Each expert page names the person, the target, their stated reasoning, and the primary source, so you can weigh the claim yourself. For lab-standard versus functional-medicine "optimal" ranges broadly, see the optimal blood test ranges guide.
Monitoring your response to a prescribed therapy is a separate trust model, covered in the Peptides & Hormones section: medically reviewed before-and-after blood work for TRT, GLP-1, and other therapies, anchored to clinical guidelines rather than an individual expert's stated protocol.
Start with your own numbers
Both calculators run in your browser and send nothing anywhere. Enter values from a lab report.
Expert panels
Where the experts overlap
Count is how many of the 10 people in our sourced database cite a target for that marker. It records who has said something, not which markers matter most. The target numbers stay on each expert page, next to their source.
| Marker | Tracked by | Count |
|---|---|---|
| ApoB | Peter Attia, Andrew Huberman, Bryan Johnson, Casey Means | 4 |
| Fasting Insulin | Robert Lustig, Casey Means, Peter Attia, Bryan Johnson | 4 |
| HbA1c | Tim Ferriss, Peter Attia, Bryan Johnson, Casey Means | 4 |
| Fasting glucose | Peter Attia, Casey Means, Robert Lustig | 3 |
| HDL Cholesterol | Peter Attia, Casey Means, Matthew Walker | 3 |
| hs-CRP | Tim Ferriss, Peter Attia, Bryan Johnson | 3 |
| Testosterone | Peter Attia, Andrew Huberman, Tim Ferriss | 3 |
| Vitamin D | Rhonda Patrick, Andrew Huberman, Bryan Johnson | 3 |
| Albumin | Bryan Johnson, Peter Attia | 2 |
| Cortisol | Andrew Huberman, Matthew Walker | 2 |
| Ferritin | Rhonda Patrick, Bryan Johnson | 2 |
| Homocysteine | Peter Attia, David Sinclair | 2 |
| IGF-1 (Somatomedin C) | Valter Longo, Peter Attia | 2 |
| Uric Acid | Peter Attia, Robert Lustig | 2 |
| Vitamin B12 | Peter Attia, David Sinclair | 2 |
| ALT | Peter Attia | 1 |
| AST | Peter Attia | 1 |
| eGFR | Peter Attia | 1 |
| Lipoprotein(a) | Peter Attia | 1 |
| Magnesium | Rhonda Patrick | 1 |
| Omega-3 Index | Rhonda Patrick | 1 |
| Triglycerides | Peter Attia | 1 |
Markers longevity experts track
Each page covers what the marker measures and how to read your result. The line under each card lists who cites a target for it in our database.
From the blog
Dated commentary on new findings and claims. Read these as reports of what a study or person said, not as settled guidance.
Already have lab results? See where you land.
Upload your blood report and FixFirst checks it against the standard clinical thresholds these expert targets are measured against, adjusted for your sex and context.
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