Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

MASLD, metabolic dysfunction-associated steatotic liver disease, is hepatic steatosis affecting at least five percent of hepatocytes in someone with at least one cardiometabolic criterion, such as raised waist circumference, dysglycaemia, hypertension or atherogenic dyslipidaemia. The 2023 multi-society consensus replaced non-alcoholic fatty liver disease, dropping a label defined by what the patient did not have, and added MetALD for the group with both metabolic risk and meaningful alcohol intake. Steatotic liver disease is the umbrella term above all of these.

It is the most common chronic liver disease in the world, affecting roughly a third of adults on pooled imaging estimates, and tracks obesity and type 2 diabetes closely. Quantification is by magnetic resonance proton density fat fraction, which reports liver fat as a percentage, or less precisely by ultrasound and controlled attenuation parameter. Risk stratification uses fibrosis, not fat: FIB-4 from age, transaminases and platelets as a first pass, then elastography or a fibrosis panel above the low-risk threshold.

The clinical point is that MASLD is common and, for most people who have it, indolent. What predicts cirrhosis, liver cancer and liver-related death is fibrosis stage, which is why every serious pathway triages on fibrosis rather than on the presence of fat. Cardiovascular disease still kills more of this population than their livers do.

Two misreadings are routine. A bright liver on ultrasound is treated as a diagnosis when it neither quantifies fat nor says anything about inflammation or scarring. And normal transaminases are read as exclusion, when a substantial fraction of people with advanced fibrosis have an ALT inside the reference range. Any product claiming to reverse fatty liver is claiming an endpoint that weight loss alone moves, and moves early.