Haematocrit: what your result means.

Haematocrit measures the percentage of blood volume occupied by red blood cells. It reflects both red cell production and plasma volume, making it sensitive to dehydration, altitude, and blood loss. Longevity-focused interpretation targets mid-range values. Haematocrit is measured by blood test as part of the Organ panel in the HodieLabs Health Blueprint.

Why Haematocrit matters

Dehydration is the most common cause of mildly elevated haematocrit. Ensure adequate hydration before testing. Altitude and endurance training physiologically elevate haematocrit.

Associated risks when out of range: Elevated haematocrit increases blood viscosity and thrombotic risk. Low haematocrit indicates anaemia or haemodilution.

Evidence basis

The HodieLabs Evidence-Based Clinical Library classifies Haematocrit as an strong evidence-tier biomarker. Its reference ranges come from a published authority standard rather than from observational optimisation targets. The standard used here is RCPA Australian pathology reference intervals; haematocrit 0.40–0.54 L/L (male) / 0.36–0.47 L/L (female). Where relevant clinical outcomes are noted on this page, they reflect the guideline literature referenced below.

Evidence-based reference ranges

The HodieLabs Evidence-Based Clinical Library interprets Haematocrit against published clinical authority standards, never arbitrary "optimal" ranges. Measured in L/L:

Clinical interpretation

• Dehydration is the most common cause of mildly elevated haematocrit. Ensure adequate hydration before testing.
• Altitude and endurance training physiologically elevate haematocrit.
• Haematocrit >52% in men or >48% in women warrants investigation for polycythaemia vera.

What improves it: the evidence-based levers

• Interpret with haemoglobin and RBC count to distinguish true polycythaemia from dehydration
• Investigate cause if persistently abnormal. Iron studies, B12, folate, EPO

Recommended testing frequency: Annual, as part of a comprehensive panel. Single markers are always interpreted in context.

How Haematocrit testing works at HodieLabs

Haematocrit is measured in every Health Blueprint at our Melbourne Preventative Health & Longevity Clinic, interpreted by a doctor against the guideline-cited ranges above and tracked over time through your HodieLabs membership.

References

1. RCPA Australian pathology reference intervals; haematocrit 0.40–0.54 L/L (male) / 0.36–0.47 L/L (female).

This page is general information from the HodieLabs Evidence-Based Clinical Library, not medical advice. Speak with your GP about what testing and care is appropriate for you.