01 — MASLD AND MASH
Fat in the liver is common; scarring determines much of the long-term risk
Metabolic dysfunction–associated steatotic liver disease (MASLD), formerly called NAFLD, describes excess liver fat in a person with metabolic risk. Metabolic dysfunction–associated steatohepatitis (MASH), formerly NASH, includes liver-cell injury and inflammation that can progress to fibrosis, cirrhosis, liver failure or liver cancer.
Many people have simple steatosis without advanced disease. The central task is not merely to confirm fat on an ultrasound; it is to assess fibrosis risk and manage diabetes, weight, blood pressure, cholesterol, sleep apnea and cardiovascular risk.
02 — RISK AND SYMPTOMS
A silent disease may exist with normal-looking health
MASLD often causes no symptoms. Fatigue or right-upper abdominal discomfort is nonspecific. Risk rises with type 2 diabetes, obesity, central adiposity, high triglycerides, metabolic syndrome and sleep apnea. Genetics and ethnicity also influence risk; a person does not need to have obesity.
Normal liver enzymes do not exclude important fibrosis, and elevated ALT does not establish MASH. Alcohol, viral hepatitis, medicines, autoimmune disease and other liver conditions must be considered.
03 — DIAGNOSIS
Confirm steatosis, metabolic context and competing causes
NIDDK ↗ describes history, examination, blood tests, imaging and sometimes biopsy. Review alcohol honestly, including binge patterns; prescriptions, over-the-counter products and supplements; viral risks; family history and metabolic disease.
Ultrasound, CT or MRI can show liver fat but routine imaging cannot reliably distinguish simple fat from inflammation or stage fibrosis. Liver biopsy is reserved for selected uncertainty or when results will change treatment.
04 — NONINVASIVE FIBROSIS ASSESSMENT
Use a staged pathway instead of guessing from ALT
Scores such as FIB-4 use age, AST, ALT and platelets to identify people at low or higher risk. Higher or indeterminate results may lead to vibration-controlled transient elastography, enhanced liver fibrosis testing, magnetic resonance elastography or specialist review. Cutoffs depend on age and clinical setting.
A single result can be distorted by acute illness or inflammation. Repeat testing intervals depend on diabetes and metabolic risk. Advanced fibrosis changes surveillance, medication and referral decisions.
05 — WEIGHT AND FOOD
Gradual, sustained change can reduce fat, inflammation and fibrosis
For people with overweight or obesity, loss of roughly 3–5% may reduce liver fat, while larger sustained loss—often around 7–10%—may be needed for inflammation and fibrosis improvement. Response varies. Rapid crash loss and malnutrition can worsen liver health.
A Mediterranean-style pattern, fewer sugar-sweetened drinks and refined carbohydrates, more fiber, vegetables, legumes, whole grains and unsaturated fats support liver and cardiovascular health. The best plan fits diabetes, kidney disease, culture, budget and long-term adherence. Fructose is not a license to ban whole fruit; concentrated sugary drinks are the more practical target.
06 — ACTIVITY AND METABOLIC CARE
Exercise helps even without major weight loss
Aerobic and resistance activity can reduce liver fat and improve insulin sensitivity. Build gradually toward regular weekly activity while preserving muscle. Treat diabetes, hypertension, cholesterol and sleep apnea. Statins are often appropriate for cardiovascular risk and should not be withheld automatically because of stable MASLD.
Weight-management medicines or bariatric surgery may improve metabolic disease and liver outcomes in eligible patients, but they require their own safety assessment and long-term follow-up.
07 — LIVER-DIRECTED MEDICINES
Eligibility depends on confirmed disease stage
Resmetirom was FDA-approved under accelerated approval for selected adults with noncirrhotic MASH and moderate-to-advanced fibrosis, alongside diet and exercise. It is not a general supplement for anyone with fatty liver. Thyroid, liver, gallbladder, lipid and drug-interaction considerations require specialist management.
Semaglutide has also gained a MASH indication in selected patients under accelerated approval. Product labels and regional approvals change, so treatment must use current prescribing information. Vitamin E or pioglitazone may be considered in selected clinical contexts but are not universal and carry risks.
08 — ALCOHOL, MEDICINES AND SUPPLEMENTS
“Liver detox” can become liver injury
Alcohol can add injury to metabolic liver disease; safe advice depends on fibrosis and individual risk, and advanced disease generally requires abstinence. Review acetaminophen dose and every supplement. Do not stop needed prescriptions without advice.
Milk thistle has not established an ability to reverse MASH or fibrosis. Green-tea extracts, multi-herb detoxes, bodybuilding products and concentrated botanicals can injure the liver or interact with treatment. Coffee may be associated with liver benefit in observational research, but it is not a substitute for fibrosis care.
09 — ADVANCED FIBROSIS AND CIRRHOSIS
Complications require specialist surveillance
Cirrhosis may lead to portal hypertension, fluid accumulation, variceal bleeding, confusion, infection and liver cancer. People with cirrhosis need specialist monitoring, vaccinations, medicine review, nutrition planning and appropriate cancer or varices surveillance. Liver transplantation may be considered for liver failure or selected cancer.
10 — PRACTICAL PLAN
- Confirm context.Review metabolic risk, alcohol, medicines and competing liver diseases.
- Stage fibrosis.Calculate a validated score and obtain second-line testing when indicated.
- Choose sustainable change.Set food, activity and gradual weight goals that preserve muscle.
- Treat the whole risk.Control diabetes, blood pressure, lipids and sleep apnea.
- Remove hazards.Avoid binge alcohol and unverified liver-detox products.
- Schedule reassessment.Repeat fibrosis and metabolic monitoring at a risk-appropriate interval.
11 — URGENT SAFETY
Emergency assessment is needed for vomiting blood, black stools, severe confusion or unusual sleepiness, rapidly increasing abdominal swelling, fainting, fever with advanced liver disease, severe persistent abdominal pain or rapidly worsening jaundice.
Prompt review is needed for new jaundice, dark urine, pale stools, leg swelling, easy bleeding, unexplained weight loss or suspected supplement-related injury.
12 — VERIFIED REFERENCES