Who progresses to serious scarring

Most people with fat never develop significant fibrosis; predicting who will is still imprecise, though non-invasive tests (FIB-4, elastography) help triage.

The long-term outcome benefit of new drugs

Resmetirom improved liver histology, but whether it reduces cirrhosis, transplants and deaths over years is not yet proven.

Fatty liver (MASLD), honestly — common, silent, and mostly reversible

Fatty liver affects roughly a quarter to a third of adults, is usually silent, and its danger tracks with scarring (fibrosis) — while the best-evidenced treatment remains losing 7–10% of your body weight.

What it is, and why it’s silent

Fatty liver disease — recently renamed MASLD (metabolic dysfunction-associated steatotic liver disease), formerly NAFLD — is fat building up in the liver alongside a metabolic risk factor like excess weight, high blood sugar or high triglycerides. It is the liver arm of metabolic syndrome.

It usually causes no symptoms until it is advanced, so most people don’t know they have it. It ranges from simple fat (steatosis) to fat plus inflammation (MASH/NASH) to scarring (fibrosis) and, at the far end, cirrhosis.

What the evidence shows

Common, but the risk is in the scarring.

It’s very common — Pooled global prevalence is around 30% of adults (roughly a quarter to a third depending on the data), and much higher with obesity or type-2 diabetes. (established)
Fibrosis stage — not inflammation — predicts the danger — Across long-term studies, the amount of scarring (fibrosis stage) is the strongest predictor of liver-related and overall death, stepping up with each stage. Simple fat alone is far lower risk. (established)
Losing 7–10% of body weight is the best treatment — In biopsy-proven patients, ≥7–10% weight loss improved inflammation and disease resolution, and ≥10% drove fibrosis to regress. It’s the best-evidenced treatment there is — more than any supplement. (established)

The honest extras

Coffee is an association, not a treatment — Coffee drinking is linked with less liver fibrosis, but this is observational — no trial shows coffee treats fatty liver. A reasonable habit, not a therapy. (note)
A drug now exists — but weight loss stays first — Resmetirom (Rezdiffra) became the first FDA-approved drug for MASH (2024, accelerated approval) for moderate-to-advanced fibrosis. Long-term outcome data are still pending, and it is an add-on to weight loss and metabolic control, not a replacement. (emerging)
Alcohol makes it worse — Alcohol adds its own liver injury on top of metabolic fatty liver; cutting down matters, especially with any fibrosis. (note)

What we still don’t know

Who progresses to serious scarring Most people with fat never develop significant fibrosis; predicting who will is still imprecise, though non-invasive tests (FIB-4, elastography) help triage.
The long-term outcome benefit of new drugs Resmetirom improved liver histology, but whether it reduces cirrhosis, transplants and deaths over years is not yet proven.

Key terms

MASLD Metabolic dysfunction-associated steatotic liver disease — fatty liver plus a metabolic risk factor; the new name for most NAFLD.
Steatosis Simple fat in the liver — the earliest, lowest-risk stage.
MASH / NASH Fat plus inflammation and injury — the progressive form.
Fibrosis Liver scarring (stage 0–4); the stage is the key predictor of outcome.
Cirrhosis Advanced, stage-4 scarring of the liver.
FIB-4 / elastography Non-invasive tests that estimate fibrosis and help decide who needs closer assessment.