Haemoglobin
In one sentence
Haemoglobin is the iron-containing protein inside red blood cells that carries oxygen from lungs to tissues.
Haemoglobin is the iron-containing protein inside red blood cells that carries oxygen from lungs to tissues.
Why it matters
Low haemoglobin — anaemia — explains fatigue, breathlessness and pale skin, and always has a cause worth finding: iron deficiency, blood loss, chronic disease or vitamin shortfalls. Surgeons also check it before operations, because starting low magnifies blood-loss risk.
When to seek advice
A mildly low value deserves a repeat test with iron studies, not a guessed supplement. Falling values, or symptoms at rest, deserve prompt assessment.
Patient education
Definitions explain terms; they do not interpret your individual results or replace a consultation.