Definition
Fatty liver (hepatic steatosis) is a condition characterized by excessive fat accumulation in hepatocytes. It is classified into alcoholic fatty liver (due to excessive alcohol consumption) and non-alcoholic fatty liver disease (NAFLD), primarily associated with metabolic disorders.

Pathogenesis
In non-alcoholic fatty liver disease, fat accumulation is related to insulin resistance, obesity, diabetes, and hyperlipidemia. Chronic inflammation can lead to progressive liver damage, such as steatohepatitis and cirrhosis.

Diagnosis
Diagnosis is typically made using imaging techniques such as ultrasound, CT, or MRI. Elastography and, in specific cases, liver biopsy may be used to assess inflammation or fibrosis.

Treatment
Treatment includes lifestyle changes such as weight loss, a healthy diet (high in fiber and low in fat), and regular exercise. Alcohol cessation is critical for alcoholic fatty liver disease. In cases of steatohepatitis or advanced fibrosis, medication and close monitoring by a hepatologist may be required. Early intervention reduces the risk of complications like cirrhosis or hepatocellular carcinoma.


Key figures: Losing about 5 percent of body weight improves steatosis, while 7 to 10 percent is associated with improvement in inflammation and, in many patients, regression of fibrosis. FIB-4 serves as the first filter, elastography as the second step.

With progressive fibrosis, cirrhosis may develop, with complications such as varices and hepatocellular carcinoma.

Key figures

  • 5 percent weight loss improves steatosis
  • 7 to 10 percent improves inflammation and often fibrosis
  • FIB-4 is the first filter, elastography the second step
  • Ultrasound grade does not indicate disease severity

Frequently asked questions

The grade on ultrasound is a semi quantitative estimate of how much fat is present. It does not indicate the severity of the disease, because it measures neither inflammation nor fibrosis, which are what determine prognosis. A patient with grade 3 steatosis and no fibrosis is in a better position than one with grade 1 and advanced fibrosis.

It is the same disease under a more precise name. NAFLD was defined by what it was not. MASLD is defined positively, as steatosis together with at least one cardiometabolic risk factor such as increased waist circumference, raised blood sugar, hypertension or dyslipidaemia. NASH is correspondingly now called MASH.

To a large extent yes. Losing around 5 percent of body weight improves steatosis, while greater weight loss is associated with improvement in inflammation and, in many patients, regression of fibrosis. Mediterranean style eating with reduced added sugars, regular exercise, limiting alcohol and control of diabetes and lipids are the main tools.

Sources


Content last updated: September 2026 (22/09/2026).