🫁 Hepatology

Fatty Liver Disease (MASLD)

Excess fat in the liver linked to metabolic risk — the most common chronic liver disease worldwide.

Overview

Metabolic-dysfunction-associated steatotic liver disease (MASLD, previously NAFLD) affects up to 30% of adults. A subset progresses to steatohepatitis (MASH), fibrosis and cirrhosis. Early detection and metabolic optimisation can reverse progression.

Symptoms

  • Usually asymptomatic
  • Right upper quadrant discomfort or fatigue
  • Hepatomegaly on examination
  • Signs of advanced liver disease only when cirrhosis develops

Risk factors

  • Obesity, type 2 diabetes, dyslipidaemia, hypertension
  • PCOS, hypothyroidism
  • Age >50
  • South Asian ancestry

Causes

  • Insulin resistance and metabolic syndrome
  • Genetic factors (PNPLA3, TM6SF2)
  • Concurrent alcohol may accelerate (MetALD)
  • Drugs (amiodarone, methotrexate, tamoxifen)

🚨 Red flags — seek urgent care

  • Jaundice, ascites, encephalopathy — advanced disease
  • Variceal bleeding (haematemesis, melaena)
  • Rapidly rising transaminases — alternative cause likely

When to seek care

  • Incidental fatty liver on ultrasound
  • Persistently raised ALT with metabolic risk
  • Type 2 diabetes — screen for advanced fibrosis

Diagnosis

  • Liver ultrasound or controlled-attenuation parameter (CAP)
  • Exclude alcohol, viral hepatitis, autoimmune, haemochromatosis, Wilson's
  • Risk stratify with FIB-4; ELF, FibroScan if intermediate/high
  • Liver biopsy only if diagnosis uncertain or advanced fibrosis suspected

Treatment

  • Weight loss ≥7% reverses steatosis; ≥10% reverses fibrosis
  • Mediterranean diet; reduce sugar-sweetened beverages and ultra-processed food
  • ≥150 minutes/week moderate aerobic activity plus resistance training
  • Optimise diabetes (GLP-1 agonists, pioglitazone where appropriate), lipids, BP
  • Resmetirom (where licensed) for biopsy-proven MASH with fibrosis F2–F3
  • Avoid alcohol; vaccinate against hepatitis A and B

Prevention

  • Maintain healthy weight, active lifestyle, balanced diet
  • Control diabetes and metabolic syndrome
  • Limit alcohol

Complications

  • Steatohepatitis (MASH), fibrosis, cirrhosis
  • Hepatocellular carcinoma
  • Cardiovascular disease — leading cause of death in MASLD
  • Type 2 diabetes progression

Prognosis

Simple steatosis has good prognosis with lifestyle change. MASH with fibrosis carries higher liver and cardiovascular mortality but is often reversible if addressed early.

Education & self-care

MASLD is metabolic disease that happens to live in the liver. Treating the metabolic root — weight, diet, activity, diabetes control — protects the liver and the heart at the same time.

Frequently asked questions

Can fatty liver be reversed?

Yes — sustained weight loss of 7–10% can reverse fat and even early fibrosis.

Do I still need to avoid alcohol?

Alcohol accelerates MASLD progression. Minimising or avoiding it is strongly recommended.

Can fatty liver be reversed?

Yes. A sustained 7–10% weight loss can reverse steatohepatitis and even early fibrosis. Mediterranean-style eating, regular activity and reducing fructose-sweetened drinks all help.

Do I need a liver biopsy?

Most people do not. Non-invasive tools — FIB-4 score, ELF blood test and FibroScan elastography — accurately identify those at low risk and flag the minority needing biopsy or specialist referral.

Is alcohol safe in fatty liver disease?

Even moderate alcohol accelerates fibrosis in metabolic-associated fatty liver. The safest level is none, and certainly under 14 units a week spread across the week.

Medically reviewed by Dr. Handel Emery, MD, FRCP (UK) · Last reviewed 2026-06-08