AST (Aspartate Aminotransferase)

Enzyme found in liver and other tissues

21/22Providers
Liver FunctionCategory
10-40 U/LReference
Widely Available

21 of 22 providers

Category

Liver Function

Reference Range

10-40 U/L

What is AST (Aspartate Aminotransferase)?

AST (Aspartate Aminotransferase) is an enzyme found in multiple tissues including liver, heart muscle, skeletal muscle, kidneys, and red blood cells. When these tissues are damaged, AST is released into the bloodstream. While less liver-specific than ALT, AST is valuable when interpreted alongside ALT and other markers.

The AST/ALT ratio is particularly diagnostic:A ratio less than 1 (AST lower than ALT) typically indicates non-alcoholic fatty liver disease, while a ratio greater than 2 suggests alcoholic liver disease or advanced cirrhosis. AST is also crucial for detecting heart damage (elevated after heart attacks), muscle injury (rhabdomyolysis), and hemolysis (red blood cell breakdown).

AST exists in two forms:cytoplasmic AST (released with mild injury) and mitochondrial AST (released with severe injury). Very high AST levels (>1000 U/L) suggest acute hepatocellular necrosis from causes like viral hepatitis, drug toxicity, or ischemic injury. Like ALT, optimal AST levels for longevity are lower than conventional reference ranges.

Why AST Matters Beyond the Liver

  • Differential diagnosis:AST/ALT ratio helps distinguish alcoholic from non-alcoholic liver disease, and acute from chronic injury
  • Multi-organ damage detection:Unlike ALT, elevated AST can indicate heart attack, muscle breakdown, or hemolysis, not just liver disease
  • Severity indicator:Very high AST (>10x upper limit) indicates severe acute injury requiring urgent intervention
  • Fibrosis progression:Rising AST/ALT ratio over time suggests advancing liver fibrosis or cirrhosis
  • Metabolic health marker:Like ALT, elevated AST in the "high-normal"range correlates with insulin resistance and cardiovascular risk

Optimal vs Standard Ranges

Optimal (Longevity)
Men:<25 U/L, Women:<20 U/L▼
  • Associated with optimal metabolic health and lowest cardiovascular risk
  • Studies show these levels correlate with reduced mortality and better long-term health outcomes
  • Maintain AST/ALT ratio between 0.8-1.3 for optimal health
Borderline Elevated
Men:25-40 U/L, Women:20-35 U/L▼
  • Often within standard reference range but may indicate early metabolic dysfunction, mild fatty liver, or subclinical muscle/heart issues
  • Check AST/ALT ratio and consider lifestyle modifications
  • Retest in 3-6 months
Moderately Elevated
40-150 U/L▼
  • Indicates tissue damage requiring investigation
  • Check ALT, CK (creatine kinase for muscle), troponin (for heart), and liver imaging
  • If AST/ALT ratio >2, consider alcohol use or advanced liver disease
  • If AST elevated alone with normal ALT, consider heart or muscle source
Severely Elevated
>150 U/L▼
  • Indicates significant acute injury
  • Levels >1000 U/L suggest acute hepatitis, drug-induced liver injury, ischemic hepatitis, or myocardial infarction
  • Requires urgent medical evaluation, comprehensive workup including troponin, CK, hepatitis panel, and imaging
  • Very high levels (>10,000) indicate massive tissue necrosis
Standard lab range: 10-40 U/L
Sources:PMID:31425154, PMID:18302294, PMID:24633141

Scientific Evidence

AST/ALT Ratio for Diagnosis

The AST/ALT ratio is highly diagnostic for distinguishing causes of liver injury. Ratio <1 (AST lower than ALT) typically indicates NAFLD or acute viral hepatitis. Ratio >2 strongly suggests alcoholic liver disease with 70-80% sensitivity and specificity. Progressive increase in AST/ALT ratio over time indicates advancing fibrosis toward cirrhosis.

Source:Nyblom H, et al. The AST/ALT ratio as an indicator of cirrhosis in patients with PBC. Liver Int. 2006;26(7):840-845. (PubMed)

AST and Cardiovascular Mortality

Large population studies show elevated AST independently predicts cardiovascular mortality and all-cause death. Even mild elevations in the "high-normal"range (30-40 U/L) are associated with increased cardiovascular events. Each standard deviation increase in AST raises mortality risk by approximately 20%.

Source:Ndrepepa G, et al. Aspartate aminotransferase and mortality in patients with ischemic heart disease. Clin Chim Acta. 2017;466:135-140. (PubMed)

Mitochondrial AST in Severe Liver Injury

In acute liver injury, mitochondrial AST (mAST) is released from damaged mitochondria. The mAST/total AST ratio correlates with severity of hepatocellular necrosis. Very high AST levels (>10,000 U/L) almost always involve significant mitochondrial damage and indicate severe acute hepatitis, toxicity, or ischemic injury requiring urgent intervention.

Source:Kaplan MM. Serum aminotransferases and other markers of hepatocellular necrosis and inflammation. In:Hepatology:A Textbook of Liver Disease. 1996.

Statin-Induced Liver Enzyme Elevation

Statins cause mild AST/ALT elevation in 0.5-3% of patients. Most elevations are transient and clinically insignificant. However, persistent elevation >3x upper limit warrants statin discontinuation or dose reduction. Coenzyme Q10 supplementation may help reduce statin-related enzyme elevations without compromising efficacy.

Source:Russo MW, et al. Liver transplantation for acute liver failure from drug induced liver injury in the United States. Liver Transpl. 2004;10(8):1018-1023.

Exercise-Induced AST Elevation

Intense or unaccustomed exercise can significantly elevate AST (and CK) due to muscle damage, with levels potentially reaching 200-500 U/L. This is typically benign and resolves within 3-7 days with rest. Athletes should avoid testing within 48-72 hours of intense training to prevent misdiagnosis. Persistent elevation requires investigation.

Source:Brancaccio P, et al. Biochemical markers of muscular damage. Clin Chem Lab Med. 2007;45(6):757-762.

Which Providers Test AST (Aspartate Aminotransferase)?

Superpower
Included in panel
Blueprint
Included in panel
Mito Health
Included in panel
WHOOP
Included in panel
Function
Included in panel
InsideTracker
Included in panel
Marek Base
Included in panel
Marek Comp.
Included in panel
Marek Complete
Included in panel
Marek Exec.
Included in panel
Life Ext.
Included in panel
Labcorp
Included in panel
Everlywell
Included in panel
Empirical Health
Included in panel
Oura
Included in panel
SiPhox Health
Included in panel
Healthspan
Included in panel
Hims Base
Included in panel
Hims Adv.
Included in panel
Vitality Std
Included in panel
Vitality Elite
Included in panel

Full Provider Comparison

ProviderIncludesAnnual CostBiomarkers
SuperpowerSuperpower✓$199100+ (150 with ratios)
WHOOP Advanced LabsWHOOP Advanced Labs✓$34965
Labcorp OnDemandLabcorp OnDemand✓$39830+
Life ExtensionLife Extension✓$48640+
EverlywellEverlywell✓$444288
Mito HealthMito Health✓$349100+
InsideTrackerInsideTracker✓$76154
Function HealthFunction Health✓$365160+
Marek Health BaseMarek Health Base✓$25065
Marek Health ComprehensiveMarek Health Comprehensive✓$49570+
Marek Health CompleteMarek Health Complete✓$895100+
Marek Health ExecutiveMarek Health Executive✓$1950150+
BlueprintBlueprint✓$37580+
Quest HealthQuest Health—$Varies75+
Empirical HealthEmpirical Health✓$190100+
Oura Health PanelsOura Health Panels✓$9950
SiPhox HealthSiPhox Health✓$12460
Hims Labs BaseHims Labs Base✓$19950
Hims Labs AdvancedHims Labs Advanced✓$499120+
HealthspanHealthspan✓$418870-80+
Vitality Blueprint StandardVitality Blueprint Standard✓$37585
Vitality Blueprint EliteVitality Blueprint Elite✓$700128

Related Biomarkers

Other biomarkers in the Liver Function category:

ALT (Alanine Aminotransferase) ALP (Alkaline Phosphatase) GGT (Gamma-Glutamyl Transferase) Bilirubin (Total) Albumin Total Protein Globulin Lipase

Frequently Asked Questions

What is AST (Aspartate Aminotransferase)?

Enzyme found in liver and other tissues

What is the optimal range for AST (Aspartate Aminotransferase)?

The standard reference range for AST (Aspartate Aminotransferase) is 10-40 U/L. Optimal ranges may differ based on individual health goals and expert recommendations.

Which blood test providers include AST (Aspartate Aminotransferase)?

21 out of 22 blood testing providers include AST (Aspartate Aminotransferase) in their panels. This biomarker is widely available across major providers.

What category does AST (Aspartate Aminotransferase) fall under?

AST (Aspartate Aminotransferase) is categorized under Liver Function. This category includes biomarkers that help assess related aspects of health and wellness.

Medical Disclaimer

This information is for educational purposes only and is not medical advice. Always consult with a qualified healthcare provider about your specific health needs.

Last reviewed:2026-02-20