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Learn · Red Cells & Oxygen

Hematocrit (HCT)

Measured in %

The percentage of your blood made up of red cells — essentially how thick your blood is. Too thick means higher clot, stroke and heart attack risk.

What the numbers mean

These are the ranges BioForge works to. They are not the same as a lab's reference range, which is built from the general population rather than from people who feel well.

Low
<38.5 · Anemia work-up
Optimal
40–47 · Ideal pre-treatment
High
→ >50 hold & · investigate · → >52 act · ≥ → 54 stop therapy

What moves Hematocrit (HCT)

Testosterone raises it — injections raise it the most. Also raised by sleep apnea, smoking and vaping, dehydration, altitude, kidney disease, and higher or less frequent dosing. Lowered by blood donation, therapeutic phlebotomy, and dose reduction.

Related markers in Red Cells & Oxygen

This page is educational and is not medical advice. Ranges are general and do not account for your history, medications or symptoms — a single number never decides a protocol. Your results are interpreted by a licensed clinician alongside everything else about you. Back to the Learning Center

Results Start Here

Want to know where your numbers actually sit?

Every BioForge protocol starts from your own bloodwork. The first 15-to-30-minute call is free.

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