Fatty liver (MASLD/MASH)
MASLD (metabolic dysfunction-associated steatotic liver disease, formerly known as NAFLD) is a build-up of fat in the liver linked to insulin resistance; MASH (formerly NASH) is a more advanced form involving liver inflammation.
Symptoms
- Usually no symptoms in early stages — often found incidentally on imaging or blood tests
- Fatigue or discomfort in the upper right abdomen in some cases
- Signs of advanced liver disease in later stages, which need prompt evaluation
Causes & risk factors
- Insulin resistance and type 2 diabetes
- Obesity, particularly abdominal obesity
- Dyslipidemia
- MetALD — a related category for MASLD alongside alcohol intake above defined thresholds
How it’s diagnosed
Diagnosis typically starts with blood tests and liver ultrasound; further evaluation (such as elastography or, in some cases, biopsy) may be coordinated through partner facilities to assess severity.
How it’s treated
Management centers on treating the underlying metabolic drivers — weight, glucose, and lipid management — since there is currently no medication approved specifically to reverse fatty liver alone; some diabetes and weight-management therapies have shown liver benefits as a secondary effect.
When to seek care
- Yellowing of the skin or eyes (jaundice)
- Significant abdominal swelling
- Unexplained, ongoing abdominal pain
FAQ
Why did the name change from NAFLD/NASH to MASLD/MASH?
A 2023 multi-society consensus renamed these conditions to reflect their metabolic basis more precisely. The conditions themselves are the same; MASLD/MASH is simply the current terminology.
Sources
- AASLD and the multi-society Delphi consensus (2023) on MASLD/MASH nomenclature
- American Diabetes Association, Standards of Care in Diabetes—2026
Medical disclaimer: Content on this page is for general education and is not a substitute for individualized medical advice, diagnosis, or treatment. Outcomes vary between patients. Boston Diabetes Center is outpatient / day-care specialty centre with an on-site diagnostic lab and pharmacy — no inpatient beds; imaging and inpatient care are coordinated through partner facilities.