This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.
Screening for fatty liver without imaging
Fatty liver disease, now called MASLD (metabolic dysfunction-associated steatotic liver disease), affects about a quarter to a third of adults. It is often silent for years. The fatty liver index (FLI), developed by Giorgio Bedogni in 2006 in the Italian Dionysos study, estimates the probability of fatty liver from four routine measurements.
The formula
L = 0.953 × ln(triglycerides, mg/dL) + 0.139 × BMI + 0.718 × ln(GGT, U/L) + 0.053 × waist (cm) − 15.745
FLI = e^L ÷ (1 + e^L) × 100
The result is a score from 0 to 100, roughly the probability (in %) that an ultrasound would show fatty liver.
Example
Triglycerides of 150 mg/dL, a BMI of 27, a GGT of 35 U/L and a 38 in (96.5 cm) waist give L = 0.45 and an FLI of 61.
| FLI | Interpretation |
|---|---|
| under 30 | Fatty liver unlikely (rules it out with good sensitivity) |
| 30 to 59 | Indeterminate |
| 60 or more | Fatty liver likely |
What to do with the result
A high FLI is a reason to talk to a doctor about the liver, especially in someone with obesity, type 2 diabetes or high blood pressure. Guidelines recommend assessing liver fibrosis, which determines the prognosis, with the FIB-4 score and, if needed, elastography (FibroScan).
Limits
- Alcohol raises GGT and triglycerides; the FLI does not distinguish alcohol-related from metabolic fatty liver.
- It was validated in European adults; performance varies in other populations.
- Triglycerides should be fasting.
Lowering your risk
Losing 5 to 10% of body weight reduces liver fat substantially, and losses of 10% or more can improve inflammation and fibrosis. Regular physical activity, fewer sugary drinks and refined carbohydrates, and limiting alcohol all help.