Serum Hemoglobin (Hgb)
Hemoglobin is the iron-containing metalloprotein in erythrocytes responsible for binding and transporting molecular oxygen from pulmonary alveoli to peripheral tissue mitochondria.
Standard vs. Optimal Reference Rangesg/dL
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
13.5 - 17.5 g/dL (Male), 12.0 - 15.5 g/dL (Female)
General reference distribution across unselected commercial populations.
14.0 - 16.0 g/dL (Male), 12.5 - 14.5 g/dL (Female)
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Each tetramer consists of two alpha and two beta globin chains, each surrounding an iron-protoporphyrin IX (heme) group capable of cooperatively binding four O2 molecules with sigmoidal allosteric binding kinetics.
Differential Diagnosis
Elevated Levels (Hgb High)
- •Erythrocytosis / Chronic hypoxemia / Sleep apnea
- •Exogenous androgen or anabolic steroid use
- •Polycythemia vera
Low Levels (Hgb Low)
- •Iron deficiency anemia
- •Anemia of chronic disease / Inflammation
- •Blood loss or occult GI bleeding
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Fasting is not strictly required for standard Complete Blood Count, but consistent morning timing is advised due to circadian fluctuations in leukocyte counts. Venipuncture must be performed with minimal stasis in K2-EDTA tubes and gently inverted 8 to 10 times to prevent microclots. Dehydration causes hemoconcentration and spuriously elevates cellular counts; ensure normal fluid intake before testing.
Reflexive Testing Protocol:
- Peripheral Blood Smear with manual microscopic review to evaluate cellular morphology, poikilocytosis, and blast cells
- Reticulocyte Count and Reticulocyte Hemoglobin Equivalent (Ret-He) to assess dynamic bone marrow erythropoietic response
- Complete Iron Panel (Ferritin, Serum Iron, TIBC, Transferrin Saturation) and Soluble Transferrin Receptor
- Serum Methylmalonic Acid and Homocysteine to screen for functional Vitamin B12 and Folate deficiencies
- Hemoglobin Electrophoresis or High-Performance Liquid Chromatography (HPLC) if hemoglobinopathy or thalassemia is suspected
Clinical Citations & Primary Literature (1)
- [1]Hemoglobin Concentration and Cardiovascular Mortality: A U-Shaped Relationship - Blood (2021). PMID: 33621422
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Serum Hemoglobin (Hgb) into overall healthspan optimization.