Albumin to Globulin Ratio (A/G Ratio)
The A/G ratio compares the concentration of serum albumin (nutritional and functional biomarker) to globulins (inflammatory and immunological biomarker).
Standard vs. Optimal Reference Rangesratio
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.
1.1 - 2.5
General reference distribution across unselected commercial populations.
1.5 - 2.2
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Because albumin decreases during chronic inflammation (negative acute-phase reactant) while globulins increase (positive acute-phase reactants and immunoglobulins), the A/G ratio is a highly sensitive index of systemic inflammatory stress.
Differential Diagnosis
Elevated Levels (A/G Ratio High)
- •Optimal metabolic and nutritional health
- •Absence of chronic inflammatory stimulus
Low Levels (A/G Ratio Low)
- •Chronic liver disease / Cirrhosis
- •Autoimmune disease flare
- •Multiple myeloma
- •Chronic systemic infections
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
A 12-hour overnight fast is recommended, especially if assessing biliary markers or lipid-associated hepatic enzymes. Complete abstinence from ethanol for at least 48 to 72 hours prior to testing is mandatory to prevent enzyme induction. Avoid strenuous unaccustomed weightlifting for 48 hours prior, which can release muscular transaminases and elevate AST/ALT.
Reflexive Testing Protocol:
- Comprehensive Hepatic Viral Panel (Hepatitis A IgM, HBsAg, HBcAb, HCV antibody with reflex PCR)
- Vibration-Controlled Transient Elastography (FibroScan) or Magnetic Resonance Elastography to quantify hepatic fat and fibrosis
- Serum Ferritin and Total Iron-Binding Capacity (TIBC) to screen for hereditary hemochromatosis
- Autoimmune Liver Disease Serology (Anti-Nuclear Antibodies, Anti-Smooth Muscle Antibodies, Anti-Mitochondrial Antibodies)
- Abdominal Right Upper Quadrant Ultrasound to assess hepatic parenchyma, biliary ducts, and portal vein flow
Clinical Citations & Primary Literature (1)
- [1]Albumin-to-Globulin Ratio as a Universal Mortality Predictor across Medical Populations - JAMA Internal Medicine (2021). PMID: 33878201
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Albumin to Globulin Ratio (A/G Ratio) into overall healthspan optimization.