Skip to content

Blood count

Hemoglobin

LOINC 718-7 · g/dL

What it is

Hemoglobin is the protein in red blood cells that carries oxygen from your lungs to the rest of your body.

Why it matters

It is the central measure of anemia and of your blood's oxygen-carrying capacity.

What high values can mean

A higher value can reflect dehydration, smoking, living at altitude or an overproduction of red cells.

What low values can mean

A lower value indicates anemia, commonly from iron, B12 or folate deficiency, blood loss or chronic disease.

How to improve it

Correcting the underlying cause — often iron or vitamin levels — is what restores hemoglobin.

Food & lifestyle

Iron-rich foods with vitamin C to aid absorption, plus adequate B12 and folate, support healthy hemoglobin.

Preparing for the test

Part of a complete blood count (CBC); fasting is not required.

When to talk to a doctor

Discuss low hemoglobin with a doctor, especially with fatigue, pallor, breathlessness or a fast heartbeat.

Related markers

Sources

  • MedlinePlus (NIH)
  • Testing.com (AACC)

Content reviewed on June 26, 2026

Medical disclaimer

This content is for educational purposes only. It is not medical advice and does not diagnose, treat, or prevent any condition. Reference ranges vary between laboratories — always use the range printed on your report and discuss your results with a healthcare professional.

See your own values in context

Bllod turns your lab report PDFs into clear, tracked results — every marker organized, explained, and charted over time.