Red Blood Cells (RBC)
Red blood cells (erythrocytes) contain hemoglobin and transport oxygen. Together with hemoglobin, the count reflects oxygen-carrying capacity.
Normal ranges
Men: 4.0–5.1 ×10¹²/L. Women: 3.7–4.7 ×10¹²/L.
Units: ×10¹²/L
Causes of deviations
Low levels:
Anemia, blood loss, iron or B12 deficiency, chronic disease.
High levels:
Dehydration, smoking, high altitude, polycythemia.
When to see a doctor
If abnormal, especially with fatigue, pallor, or shortness of breath.
This information is for educational purposes and does not replace medical advice.
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