Tim Ferriss's Blood Test Panel: The 3 Markers He Tracks and Why

Tim Ferriss runs one of the smallest published panels in this series: three markers, tested on a repeating schedule rather than once a year. What separates his approach is not breadth but method — he reads the direction a marker is moving over months, on the argument that a value sitting inside the reference range while falling for a year tells you more than any single result. Below are his three markers, his stated target for each, and how those targets compare with four other protocols.

AI-curated · Expert-attributed

Compiled by AI from the named experts’ own public statements, with every figure attributed to its source. These are individual expert protocols, not clinical guidelines or FixFirst medical advice. Evidence & methodology

Every target attributed to Ferriss and sourced Compared against 4 other expert protocols Free 45-second analysis of your own results

Why three markers instead of sixteen

Ferriss is a self-experimenter rather than a physician, and his panel reflects that: a short list he can repeat often enough to see a trend, paired with continuous glucose monitoring between draws.

This page belongs to FixFirst's Longevity blood markers series, which attributes every target to the person who stated it instead of presenting it as clinical guidance. Peter Attia's panel runs to 16 markers because it is built as a physician's risk-monitoring tool. Ferriss built his around repeatability, testing on roughly a two-week to quarterly cadence so that each marker produces a line rather than a dot.

That cadence is the reason his targets are worth comparing rather than copying. Two of his three numbers are stricter than the clinical cut-off and looser than the strictest protocol in this series, which tells you these are optimisation goals, not diagnostic thresholds. FixFirst checks all three markers against standard clinical ranges if they appear on your report, not against anyone's personal target.

The three markers Ferriss tracks

One metabolic, one inflammatory, one hormonal — each shown against what other published protocols target for the same marker.

Cluster 1 of 3

Metabolic health

HbA1c reflects roughly 90 days of average blood glucose, which is why Ferriss treats it as the anchor of his panel rather than fasting glucose. He pairs it with a continuous glucose monitor so the quarterly lab number has daily data behind it. His stated target of under 5.4% sits below the 5.7% clinical prediabetes threshold, deliberately, as a buffer rather than a diagnosis line.

Core Usually in a standard panel Ask Request specifically

Core

HbA1c

Ferriss targets under 5.4%. For comparison, Peter Attia targets under 5.5%, Casey Means 5 to 5.4%, and Bryan Johnson roughly 5.0 to 5.2% — the four cluster within half a percentage point of each other, and all four sit below the 5.7% clinical threshold. The levers Ferriss cites are 10 to 15 minute post-meal walks, cutting liquid sugar, low-carbohydrate or ketogenic periods, and berberine at 500 mg three times daily with meals. Because HbA1c averages the prior three months, he retests at 90 days rather than sooner.

Cluster 2 of 3

Inflammation

High-sensitivity CRP is the inflammation marker Ferriss uses to read how diet, sleep and training load are affecting his baseline. Clinical labs generally flag values above 3.0 mg/L; his target is roughly a third of that, which again makes it an optimisation goal rather than a clinical cut-off.

Core Usually in a standard panel Ask Request specifically

Core

hs-CRP

Ferriss targets under 1.0 mg/L, the same number Peter Attia uses. Bryan Johnson runs the strictest of the three, well under 0.5 mg/L. The interventions Ferriss cites are a Mediterranean-style diet, omega-3 at 2 to 4 g of combined EPA and DHA daily, and 7 to 9 hours of sleep. One caveat he raises that most lists omit: chronic high-volume training can push CRP up rather than down, so a rising number is not automatically a diet problem.

Cluster 3 of 3

Hormones

Ferriss is the clearest example in this series of tracking a trend instead of a target. He publishes no testosterone number at all, on the reasoning that a result inside the reference range that has been declining for twelve months is more actionable than any one-off value. He tests SHBG alongside it because SHBG binds testosterone and determines how much is actually free.

Core Usually in a standard panel Ask Request specifically

Ask

Free testosterone + SHBG

Ferriss states no target value, only that free testosterone and SHBG should be read together and tracked over time. Andrew Huberman does publish ranges for the same pairing — free T 5 to 21 ng/dL, SHBG 10 to 57 nmol/L — and Peter Attia frames it as a ratio, free T at roughly 2% of total, always with SHBG. The levers Ferriss cites are sleep quality, which he correlates against tracked sleep data, plus sauna and cold exposure. He has also experimented with clomiphene, a prescription fertility drug, under physician supervision; he presents this explicitly as a personal experiment and not a consumer recommendation.

Frequently asked questions

What blood markers does Tim Ferriss track?

Ferriss tracks three markers on a repeating panel: HbA1c, high-sensitivity CRP, and free testosterone tested alongside SHBG. He runs them on roughly a two-week to quarterly cadence rather than annually, and pairs the HbA1c with a continuous glucose monitor so each lab result has daily data behind it.

What is Tim Ferriss's HbA1c target?

Under 5.4%. The clinical prediabetes threshold is 5.7%, so his target is a deliberate buffer below it rather than a diagnostic line. Peter Attia targets under 5.5%, Casey Means 5 to 5.4%, and Bryan Johnson roughly 5.0 to 5.2% — four independent protocols landing within about half a percentage point.

Why does Ferriss test SHBG alongside testosterone?

SHBG, or sex hormone binding globulin, binds testosterone in the blood and determines how much of it is free and biologically available. A total testosterone result read without SHBG can look normal while free testosterone is low. Ferriss states no target value for either, tracking the direction of travel over months instead.

What supplements does Tim Ferriss take for these markers?

For HbA1c he has cited berberine at 500 mg three times daily with meals, describing a measurable reduction. For hs-CRP he cites omega-3 at 2 to 4 g of combined EPA and DHA per day. He has also experimented with clomiphene, a prescription fertility drug, for testosterone under physician supervision, and presents that explicitly as a personal experiment rather than a recommendation.

How does Ferriss's panel compare with Peter Attia's?

Attia's panel covers 16 markers across metabolic health, lipids, inflammation, liver, kidney and hormones, built as a physician's risk-monitoring tool. Ferriss tracks three, chosen so he can repeat them often enough to read a trend. Where they overlap their targets are close: both use under 1.0 mg/L for hs-CRP, and their HbA1c targets differ by a tenth of a percentage point.

Are these targets clinical guidelines?

No. Every number on this page is a personal target Ferriss has stated publicly, and several are stricter than the clinical cut-off — his hs-CRP goal is roughly a third of the 3.0 mg/L most labs flag at. Clinical reference ranges are set to identify disease, while these are optimisation goals. FixFirst scores your results against standard clinical ranges, not against anyone's personal protocol.

Keep reading: Peter Attia's Blood Test Panel · Casey Means's Blood Test Panel · David Sinclair's Blood Test Protocol

Free · No account · 45 seconds

Already have results that include HbA1c, hs-CRP or testosterone?

Upload your blood report and FixFirst checks all three against standard clinical ranges, then tells you which one to deal with first.

Analyze My Blood Test →

Any lab PDF or phone photo · Processed in memory, never stored