AST to ALT Ratio (De Ritis Ratio) (AST/ALT Ratio)
The De Ritis ratio (AST/ALT) is a classic clinical metric that differentiates viral and metabolic liver injury (ALT > AST) from alcoholic liver disease and advanced cirrhosis (AST/ALT > 2.0).
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.
0.8 - 1.2
General reference distribution across unselected commercial populations.
0.8 - 1.0 (with both enzymes in normal low range)
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Because ALT has a longer circulating half-life (47 hours) than AST (17 hours), acute viral or steatotic liver inflammation displays ALT predominance. Advanced sinusoidal fibrosis impairs hepatic sinusoidal clearance of AST, driving the ratio above 1.5 to 2.0.
Differential Diagnosis
Elevated Levels (AST/ALT Ratio High)
- •Alcoholic liver disease (> 2.0)
- •Advanced hepatic fibrosis and cirrhosis (> 1.4)
- •Non-hepatic skeletal muscle trauma
Low Levels (AST/ALT Ratio Low)
- •Metabolic dysfunction-associated steatotic liver disease (MASLD, ratio < 1.0)
- •Acute viral hepatitis
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]The De Ritis Ratio in Modern Hepatology: Clinical Utility Beyond Alcoholism - Journal of Hepatology (2022). PMID: 35123019
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate AST to ALT Ratio (De Ritis Ratio) (AST/ALT Ratio) into overall healthspan optimization.