Liver Health Biomarkers
A guide to testing and interpretation — why non-alcoholic fatty liver disease affects roughly one-quarter of adults globally, making early detection through biomarker testing critical.
Why Liver Dysfunction Matters
The liver performs essential functions including metabolism, detoxification, protein synthesis, immune regulation, and hormone metabolism. When liver function declines, systemic consequences emerge — including altered glucose regulation, impaired clotting, and increased infection risk.
Because symptoms often appear only at advanced stages, biomarker testing enables early detection and prevention when interventions are most effective.
Key Liver Health Biomarkers
| Biomarker | Location | What It Indicates |
|---|---|---|
| ALT (Alanine aminotransferase) | Concentrated in liver cells | Hepatocellular injury, particularly in NAFLD |
| AST (Aspartate aminotransferase) | Liver and other tissues | AST/ALT ratio > 2 suggests alcohol-related liver disease |
| ALP (Alkaline phosphatase) | Liver, bone, intestine | Elevated with GGT suggests biliary involvement |
| GGT (Gamma-glutamyl transferase) | Bile duct cells | Biliary obstruction, alcohol use, medication effects |
| Total Bilirubin | Byproduct of hemoglobin breakdown | Conjugation capacity and bile flow |
| Albumin | Produced by hepatocytes | Synthetic function — low levels indicate chronic liver disease |
| PT/INR | Clotting factor synthesis | Liver's ability to produce coagulation proteins |
| LDH (Lactate dehydrogenase) | Multiple tissues | General tissue injury marker |
Interpreting Biomarker Patterns
Rather than relying on single measurements, clinicians evaluate patterns across multiple biomarkers to assess disease severity and guide treatment decisions.
- Elevated ALT alone — often the first sign of NAFLD or medication-related injury
- AST/ALT ratio > 2 — suggests alcohol-related liver disease or advanced fibrosis
- ALP + GGT both elevated — points to biliary obstruction or cholestatic disease
- Low albumin + elevated PT/INR — indicates significant synthetic dysfunction and chronic disease
- Elevated bilirubin — may reflect hemolysis, hepatocellular damage, or bile duct obstruction
NAFLD: The Silent Epidemic
Non-alcoholic fatty liver disease affects approximately 25% of adults globally. It progresses silently from simple steatosis (fat accumulation) through steatohepatitis (inflammation) to fibrosis and potentially cirrhosis. Early biomarker detection is the most effective intervention point.
Optimizing Liver Health
- Weight management — even 5–10% body weight reduction significantly improves liver biomarkers in NAFLD
- Dietary improvements — emphasize whole foods, reduce refined sugars and saturated fats
- Regular physical activity — both aerobic and resistance exercise reduce hepatic fat
- Alcohol reduction — even moderate consumption can elevate GGT and worsen existing liver conditions
- Comorbidity management — controlling diabetes and hypertension reduces hepatic stress
Why Routine Testing Matters
Routine liver biomarker testing offers individuals an opportunity to identify dysfunction earlier and implement preventive measures before irreversible damage occurs. This is particularly important for those with metabolic syndrome, obesity, type 2 diabetes, or regular medication use.
The liver is remarkably resilient and capable of regeneration — but only when dysfunction is caught early enough for intervention to be effective.