Complete Testing & Optimization Guide
Optimal ranges, provider comparison, and strategies to improve your AST (Aspartate Aminotransferase) levels
Included in 10 of 10 major testing providers
Liver Function
10-40 U/L
Abnormal AST (Aspartate Aminotransferase) levels can indicate underlying health issues that may go undetected without proper testing. Regular monitoring helps catch problems early when they're most treatable.
Understanding your AST (Aspartate Aminotransferase) levels enables targeted interventions, tracks treatment effectiveness, and helps optimize your overall health and performance.
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.
Bottom line: TSH and Free T4 alone miss people with conversion problems. Free T3 is the only way to know if you have enough active thyroid hormone at the tissue level.
| Range Type | Level | Clinical Significance |
|---|---|---|
| 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
Weight loss for NAFLD:7-10% body weight reduction if overweight (same as ALT)
Alcohol cessation:If AST/ALT ratio >2, eliminate alcohol completely for 3-6 months and retest
Treat viral hepatitis:Antiviral therapy for Hepatitis B or C can normalize AST
Mediterranean diet:Rich in olive oil, fish, vegetables;reduces liver inflammation
Coffee consumption:2-3 cups daily associated with lower AST and reduced fibrosis risk
If AST elevated with normal ALT, consider cardiac sources:Check troponin, ECG, and consider cardiology referral if chest pain, dyspnea, or cardiac risk factors
Manage muscle injury:If CK also elevated, identify cause (strenuous exercise, statins, rhabdomyolysis). Hydrate well and avoid intense exercise until normalized
Statin-induced myopathy:If on statins with elevated AST/CK, consider CoQ10 supplementation (100-200 mg daily) or switch to lower-potency statin
Address hemolysis:If indirect bilirubin and LDH also elevated, investigate for hemolytic anemia
Limit alcohol:Even moderate drinking can elevate AST, especially in susceptible individuals
Review medications:Statins, NSAIDs, antibiotics, acetaminophen, and many supplements can elevate AST
Avoid acetaminophen overdose:Stay under 3000 mg/day;lower if alcohol consumption or other risk factors
Herbal supplements:Many supplements (green tea extract, anabolic compounds) can cause liver injury
Environmental toxins:Minimize exposure to pesticides, industrial solvents, and cleaning chemicals
Coenzyme Q10:100-300 mg daily supports mitochondrial function and may reduce statin-related AST elevation
N-acetylcysteine (NAC):600-1200 mg daily boosts glutathione, protects against oxidative liver damage
Vitamin E:400-800 IU daily (mixed tocopherols) reduces liver inflammation in NASH
Milk thistle:140-280 mg 2-3x daily supports liver regeneration and may reduce AST
Omega-3 fatty acids:2-4g EPA+DHA daily reduces inflammation and liver fat
Regular exercise:150+ minutes/week moderate aerobic activity improves liver and cardiovascular health
Strength training:Builds healthy muscle mass and improves insulin sensitivity, but avoid overtraining
Adequate hydration:Especially important if muscle damage suspected;aim for 2-3 liters daily
Quality sleep:7-9 hours nightly;poor sleep worsens liver disease and metabolic dysfunction
Stress management:Chronic stress elevates cortisol and can worsen metabolic liver disease
Note: Low AST typically requires no treatment unless part of broader nutritional deficiency. Ensure adequate B6 intake (1.5-2 mg daily) and balanced protein consumption.
Note: Severe elevations (>500 U/L) typically cause more pronounced symptoms and warrant immediate evaluation. Acute onset of symptoms with very high AST requires emergency assessment to rule out heart attack or acute liver failure.
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.
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.
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.
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.
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.
| Provider | Includes Test | Annual Cost | Total Biomarkers |
|---|---|---|---|
 Superpower | ✓ | $199 | 100+ |
 WHOOP Advanced Labs | ✓ | $349 | 65 |
 Labcorp OnDemand | ✓ | $398 | 30+ |
| ✓ | $486 | 40+ | |
| ✓ | $468 | 83 | |
| ✓ | $798 | 100+ | |
 InsideTracker | ✓ | $680 | 48 |
 Function Health | ✓ | $499 | 100+ |
| ✓ | $900 | 70+ | |
| ✓ | $1150 | 110 | |
| — | $Varies | 75+ |
Choose from 10 providers that include this biomarker in their panels
AST (Aspartate Aminotransferase) is a liver function biomarker that Enzyme found in liver and other tissues The normal reference range is 10-40 U/L. Regular testing helps track changes and identify potential health issues early.
10 out of 10 major blood testing providers include AST (Aspartate Aminotransferase) in their standard panels. These include Superpower, Blueprint, Mito Health and others.
For most people, testing AST (Aspartate Aminotransferase) 2-4 times per year is recommended to establish baseline levels and track trends. If you have abnormal results or are actively working to optimize this biomarker, more frequent testing (quarterly) may be beneficial. Always consult with your healthcare provider for personalized testing frequency recommendations.
The standard laboratory reference range for AST (Aspartate Aminotransferase) is 10-40 U/L. However, many functional medicine practitioners recommend tighter "optimal" ranges for peak health and performance. Your ideal range may vary based on your age, sex, health goals, and other individual factors. Work with a healthcare provider familiar with optimal ranges to determine your target levels.
Most direct-to-consumer blood testing services that include AST (Aspartate Aminotransferase) provide the physician order as part of their service. However, some states have restrictions on direct-to-consumer testing. Check with your chosen provider about availability in your state and whether they provide the necessary physician authorization.
Elevated in liver disease but also heart and muscle damage. AST/ALT ratio helps differentiate causes of liver injury. Less specific than ALT for liver disease.
This information is for educational purposes only and is not medical advice. Always consult with a qualified healthcare provider about your specific health needs and before making decisions about blood testing.
