What is the normal hemoglobin (Hgb) range for adults?

The normal hemoglobin (Hgb) range for adults is 12-18 g/dL. This range reflects the amount of hemoglobin in the blood, which is crucial as hemoglobin is responsible for transporting oxygen from the lungs to the rest of the body and returning carbon dioxide from the body back to the lungs.

Men typically have hemoglobin levels that are slightly higher, often between 13.5-17.5 g/dL, while women usually fall within 12-15.5 g/dL. This is why the provided range of 12-18 g/dL is generally accepted for adults, encompassing the variations based on sex and individual factors.

The other ranges listed do not align with standard medical references for adult hemoglobin levels. A range of 10-12 g/dL indicates a possible deficiency or anemia, 15-20 g/dL is above the normal upper limit and may suggest conditions like polycythemia, and 8-10 g/dL is significantly low, which is indicative of severe anemia or other clinical concerns that require medical intervention.