Fatty liver disease (MASLD)
Also called: NAFLD, MASLD, NASH, MASH, Metabolic dysfunction-associated steatotic liver disease
Fat builds up in the liver in people who drink little alcohol, driven by obesity and insulin resistance. In some it inflames and scars the liver, leading to cirrhosis.
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About one in four adults worldwide.
What happens in the body
Excess fatty acids from diet and adipose tissue overwhelm the liver's handling, causing fat storage (steatosis); lipotoxic injury can trigger inflammation (steatohepatitis) and fibrosis.
Causes
- Insulin resistance and metabolic syndrome
Risk factors
- Obesity, especially abdominal
- Type 2 diabetes
- High triglycerides
- Hypertension
- Sleep apnoea
Symptoms
- Usually none
- Fatigue or discomfort in the upper right abdomen
- Signs of cirrhosis in advanced disease
Diagnosis — tests and examinations
- Liver blood tests (often normal)
- Ultrasound showing fatty liver
- Fibrosis scores (FIB-4) and elastography (FibroScan)
- Biopsy rarely
Treatment
Medicines and medical treatment
- Resmetirom for significant fibrosis (where approved)
- GLP-1 receptor agonists (semaglutide) help weight and liver fat
- Treat diabetes, cholesterol and blood pressure
Operations and procedures
- Bariatric surgery can reverse disease in severe obesity
- Liver transplant for end-stage disease
Self-care, home remedies and lifestyle
- Lose 7–10% of body weight
- Mediterranean-style diet, cut sugary drinks
- Regular exercise
- Avoid alcohol if there is fibrosis
Possible complications
- Cirrhosis
- Liver cancer
- Cardiovascular disease (the main cause of death)
Prevention
- Healthy weight, diet and activity
Outlook
Reversible in early stages with weight loss; progressive fibrosis carries risk of cirrhosis.
When to see a doctor
Ask your doctor to check your liver if you have obesity or diabetes; see a doctor for jaundice or abdominal swelling.
Sources and further reading
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