HCT

Percentage of blood volume occupied by red blood cells. Reflects oxygen-carrying capacity and is influenced by hydration status, altitude, and erythropoiesis.
Also known as:
Hematocrit
Ht
.

HCT ranges for

Interpret your result
"Normal" lab range for HCT is between 38.5 and 52 % for males:
38.5
52
According to OptimalDX, HCT should be between 40 and 48 % for males:
40
48
Optimal range
Optimal range for HCT appears to be between 40 and 50 % for males:
20
38.5
40
50
52
60
Why this optimal range?
Preliminary range is based on functional health organizations including but not limited to those listed above.
Your interpretation
For low
For high

Common reasons for high HCT:

  • High hematocrit suggests erythrocytosis or hemoconcentration.

    Dehydration is a common transient cause. Athletes may also have elevated hematocrit due to increased red blood cell mass from training at high altitudes.

    Chronic causes include polycythemia vera, chronic hypoxia (for example COPD, sleep apnea, smoking, high altitude, or cyanotic congenital heart disease), testosterone therapy, and excess erythropoietin production such as from renal disease or EPO-secreting tumors.

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Zsolt Szabo
Zsolt Szabo
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I am particularly interested in research on biomarkers associated with all-cause mortality and on defining optimal reference ranges.