Red blood cells (RBC)
Erythrocytes (red blood cells) carry oxygen from the lungs to the tissues (and carry away carbon dioxide) — with the help of the hemoglobin they contain. Their count is a basic part of the blood count.
| Rating | Range | What it means |
|---|---|---|
| Talk to a doctor | below 3.94 10^12/L | |
| Good | 3.94 – 5.71 10^12/L | Within the reference range. |
| Talk to a doctor | 5.71 10^12/L and above |
This marker also has 2 age- or sex-specific range sets in the app — the table shows the general one.
Why it matters
Low = anemia; interpret with hemoglobin.
If it’s low
A low erythrocyte count accompanies anemia — less oxygen transport (fatigue, pallor, breathlessness). The cause must be found (iron, B12, blood loss, bone marrow).
If it’s high
A high count is often apparent (dehydration) or a result of smoking, altitude; rarely true overproduction (polycythemia).
What to do
Interpret it with hemoglobin and the indices (MCV, MCH), which tell the type and cause. A mild abnormality when you feel well is often not serious.
Read together with
Hemoglobin · Hematocrit · MCV · MCH
Part of the guide: Complete blood count (CBC) →
Articles about this marker
- Complete blood count (CBC): what the basic blood count meansMarker explained
- High red blood cell count, hemoglobin and hematocrit: causes and what to checkComplete blood count (CBC)
This content is for information only and is not a substitute for medical advice. Talk to your doctor about your results.
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