Red Blood Cells

Complete Blood CountBlood HealthBlood

Red blood cells carry oxygen around the body. They contain hemoglobin, the substance that transports the oxygen.

Why it matters: How much oxygen reaches the body's tissues depends on how many red blood cells there are and how well they work. The count can help diagnose conditions such as iron deficiency anemia.

Source · NHS — what it is, why it matters, what moves it, related conditions

Reference Range
4.5 – 5.910x12/L
4.5
5.9LowNormalHigh
What Moves It

May increase with:

Dehydration
Smoking
Low blood oxygen levels
Pulmonary fibrosis
Congenital heart disease

May decrease with:

Iron deficiency
Vitamin B6 or B12 deficiency
Folate deficiency
Internal bleeding
Kidney disease
Malnutrition
Associated Conditions
A vitamin B6, B12 or folate deficiency, which a low count could indicateInternal bleeding, which a low count may signifyKidney disease, which a low count may signifyMalnutrition, where the diet does not contain enough nutrients to meet the body's needs, which a low count may signify
Related Markers
HemoglobinHematocritIronFerritin
Common questions

What is Red Blood Cells?

Red blood cells carry oxygen around the body. They contain hemoglobin, the substance that transports the oxygen.

What might a high or low Red Blood Cells mean?

How much oxygen reaches the body's tissues depends on how many red blood cells there are and how well they work. The count can help diagnose conditions such as iron deficiency anemia.

What is the typical reference range for Red Blood Cells?

The general-population reference range shown here is 4.5 – 5.9 10x12/L. Reference ranges describe the general population and are not a personal target — discuss your results with your physician.

What can affect Red Blood Cells?

It may be higher with: Dehydration, Smoking, Low blood oxygen levels, Pulmonary fibrosis, Congenital heart disease. It may be lower with: Iron deficiency, Vitamin B6 or B12 deficiency, Folate deficiency, Internal bleeding, Kidney disease, Malnutrition.

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