What it is: A hemoglobin test measures the amount of hemoglobin, the protein in red blood cells that carries oxygen, in the blood, typically as part of a complete blood count.
Why it's ordered: Ordered alongside a CBC to help diagnose anemia, monitor chronic conditions affecting blood, or evaluate symptoms like fatigue, weakness, or shortness of breath.
What it detects: Low hemoglobin points to anemia, which can stem from iron deficiency, blood loss, chronic disease, or bone marrow problems; high hemoglobin can reflect dehydration, smoking, lung disease, or living at high altitude.
Collection & prep: A standard blood draw from a vein in the arm, as part of a CBC. No special preparation is typically required.
Results:
Low – suggests anemia; roughly below 13 g/dL for men or 12 g/dL for women, per WHO reference ranges
High – suggests dehydration, smoking-related changes, or a red blood cell overproduction disorder
Possible complications of low hemoglobin: Untreated anemia can cause fatigue, shortness of breath, and reduced ability to exercise; abnormal results are usually followed up with iron studies or other testing to identify the specific type and cause of anemia.
Statements made in the Clinical Manual have not been evaluated by the FDA. The products mentioned are not intended to diagnose, treat, cure or prevent any disease.
