Condition: Nicht-alkoholische Fettlebererkrankung

Pooled global prevalence of non-alcoholic fatty liver disease was 25.24% (95% CI 22.10 to 28.65). Among people with the condition who were biopsied for a clinical reason, 59.10% had steatohepatitis, and cardiovascular disease was a leading cause of death, ahead of liver-specific causes. Measured in: Meta-analysis of 86 studies covering 8,515,431 people across 22 countries, imaging- and biopsy-based. Prevalence varies widely by region and by how the diagnosis was made, and the higher steatohepatitis figure comes from people biopsied because something looked wrong, so it overstates the share across everyone with fat in the liver. The estimate predates the 2023 MASLD renaming.

Vitamin E at 800 IU a day improved steatohepatitis in 43% of patients against 19% on placebo over about 2 years (p=0.001), and lowered liver enzymes. Pioglitazone improved several measures too but did not meet the trial's prespecified threshold for the primary endpoint. Measured in: 247 adults with biopsy-proven non-alcoholic steatohepatitis and without diabetes, in the PIVENS randomized placebo-controlled trial. The benefit was shown in people without diabetes; the drug arm and the diabetic population are separate questions. Long-term high-dose vitamin E has been linked in other trials to a small rise in prostate cancer risk in men and to hemorrhagic stroke, so the dose and the person matter, and it is a decision to make with a clinician after the dietary and activity basics.

Pioglitazone 45 mg daily reached the primary endpoint, a fall of 2 or more points in the activity score without worsening fibrosis, in 58% against 17% on placebo, and resolved steatohepatitis in 51% against 19%, over 18 months. Measured in: 101 adults with prediabetes or type 2 diabetes and biopsy-proven non-alcoholic steatohepatitis, randomized to pioglitazone or placebo alongside a hypocaloric diet. Both groups also followed a reduced-calorie diet, so the drug's effect sits on top of lifestyle change, not replacing it. Pioglitazone commonly causes some weight gain and fluid retention and is avoided in heart failure, so it is a considered choice for the right person, not a default.

Daily semaglutide 0.4 mg resolved steatohepatitis without worsening fibrosis in 59% against 17% on placebo over 72 weeks. Improvement in the fibrosis stage itself was not significantly different between groups, at 43% against 33%. Measured in: 320 adults with biopsy-proven non-alcoholic steatohepatitis and fibrosis stage 1 to 3, in a phase 2 placebo-controlled trial. The inflammation resolved but the scarring stage did not shift significantly over 72 weeks, which matters because fibrosis is what drives long-term outcome. Nausea and other gut effects were common. This is a drug that comes after the habits, not a substitute for them.

Over 52 weeks, steatohepatitis resolved without worsening fibrosis in 25.9% (80 mg) and 29.9% (100 mg) against 9.7% on placebo, and fibrosis improved by at least one stage in 24.2% and 25.9% against 14.2% on placebo. Both endpoints were met. Measured in: 966 adults with biopsy-confirmed steatohepatitis and fibrosis stage 1 to 3 in the MAESTRO-NASH phase 3 trial. This is the drug behind the 2024 approval, and it is the first to move both inflammation and fibrosis in a phase 3 trial, though most participants on the drug still did not reach either endpoint, and it was studied on top of standard lifestyle advice, not instead of it. Long-term outcome data, whether it prevents cirrhosis and death, is still being gathered.

At week 72, steatohepatitis resolved without worsening of fibrosis in 62.9% on weekly semaglutide 2.4 mg against 34.3% on placebo (a 28.7 point difference, P<0.001), and fibrosis improved by at least one stage without worsening of steatohepatitis in 36.8% against 22.4% on placebo (a 14.4 point difference, P<0.001). Weight fell by 10.5% against 2.0%. Measured in: Interim 72-week biopsy analysis of the first 800 of 1,197 adults with biopsy-confirmed steatohepatitis and fibrosis stage 2 or 3, randomized to weekly semaglutide 2.4 mg or placebo, in the phase 3 ESSENCE trial. This phase 3 trial reached both endpoints, including the fibrosis improvement that the earlier phase 2 trial had left open, in a much larger group. It is an interim biopsy analysis at 72 weeks within a study that continues to 240 weeks for clinical outcomes, so whether it prevents cirrhosis and death is still being measured. Gastrointestinal effects were more common on the drug. It sits on top of the diet and activity work, and it was studied alongside lifestyle advice.

Among people who lost 10% or more of their body weight over 52 weeks of lifestyle change, steatohepatitis resolved in 90%, fibrosis regressed in 45%, and all of them had some reduction in the NAFLD activity score. Benefit tracked the amount lost: resolution of steatohepatitis was far less common below 5% loss. Measured in: 293 patients with biopsy-proven non-alcoholic steatohepatitis who underwent a second liver biopsy after 52 weeks of a diet and exercise program. What could explain it instead: Self-selection by success. Whatever lets a person lose 10% of their weight in a year, more support, better health, more resources, may independently favor liver recovery, so the achieved-weight-loss gradient would look similar even if part of the effect were not the weight itself.. This is a single-arm study with no control group, so the whole cohort was trying to change at once and the comparison is between those who succeeded and those who did not. Only about a third reached 5% loss and roughly 1 in 10 reached 10%, so the striking numbers rest on the minority who managed the hardest target.

A Mediterranean diet reduced liver fat measured by magnetic resonance spectroscopy by about 39% relative to a low-fat, high-carbohydrate diet, and improved insulin sensitivity, over 6 weeks in a crossover design where weight was held stable. Measured in: 12 non-diabetic adults with biopsy-proven non-alcoholic fatty liver disease, each acting as their own control across the two diets. A very small crossover study of 12 people over a short period, with weight deliberately kept constant, so it shows the diet pattern moves liver fat on its own but not how large or durable the effect is at scale. Larger pooled trials since then agree on the direction while showing more modest average changes.

Pooling trials where diet and body weight were held steady, exercise on its own lowered the fat stored in the liver and improved related clinical markers, so the benefit does not depend on the scale moving. Measured in: Systematic review and meta-analysis of randomized controlled trials of exercise interventions in people with non-alcoholic fatty liver disease, restricted to trials without significant weight loss or dietary change. The individual trials are mostly small and short, and total weekly volume, intensity and adherence varied between them, so the pooled result confirms a direction more firmly than it pins a dose. Exercise moves liver fat further and faster when weight also comes down.

Pooling observational studies, coffee drinkers with fatty liver had about 35% lower odds of significant liver fibrosis (RR 0.65, 95% CI 0.54-0.78). Coffee was not significantly associated with a lower chance of developing fatty liver in the first place, or with how common it was. Measured in: Systematic review and meta-analysis of observational studies of coffee consumption in relation to non-alcoholic fatty liver disease incidence, prevalence and fibrosis. These are observational studies pooled together, so they show association, not proof of cause: coffee drinkers may differ from non-drinkers in ways not fully measured, and the amount and type of coffee were recorded differently across studies. It supports keeping a coffee habit, not starting a heavy one for the liver.

A diet low in free sugar (under 3% of daily calories) for 8 weeks cut liver fat measured by MRI from 25% to 17%, against essentially no change on the usual diet (21% to 20%), a significant difference favoring the sugar restriction. Measured in: 40 adolescent boys aged 11 to 16 with biopsy- or imaging-confirmed non-alcoholic fatty liver disease, randomized to a low-free-sugar diet delivered to their homes or their usual diet. The intervention diet was prepared and delivered to the families, which is more support than a family would usually have, and the trial ran only 8 weeks in a specific group, adolescent boys, so the exact number may not carry to adults or women. The direction, that added sugar drives liver fat, is well supported by the underlying biology.

Five years after bariatric surgery, steatohepatitis had resolved without worsening of fibrosis in 84% of patients with a repeat biopsy, and fibrosis had regressed in a majority, including reversal of some cases of advanced fibrosis. Measured in: 180 severely obese adults with biopsy-proven non-alcoholic steatohepatitis followed for 5 years after bariatric surgery, with serial liver biopsies. What could explain it instead: No control group and loss to follow-up. The people who returned for a 5-year biopsy are plausibly those doing better, and the surgery drives large sustained weight loss whose liver benefit cannot be separated from the operation itself.. This is a single-arm surgical cohort without a randomized comparison group, and only a subset had a full set of biopsies at 5 years, so the resolution figure describes those followed to the end, not everyone who started. Surgery carries its own operative and long-term nutritional consequences that sit outside this liver endpoint entirely.

Over 52 weeks, steatohepatitis resolved without worsening of fibrosis in 44% (5 mg), 56% (10 mg) and 62% (15 mg) against 10% on placebo (all P<0.001), and fibrosis improved by at least one stage without worsening of steatohepatitis in 51 to 55% across the three doses against 30% on placebo. Measured in: 190 adults with biopsy-confirmed steatohepatitis and moderate to severe fibrosis (stage F2 or F3) randomized to weekly tirzepatide (5, 10 or 15 mg) or placebo, with 157 evaluable second biopsies at 52 weeks, in the phase 2 SYNERGY-NASH trial. This is a phase 2 dose-finding trial of about 190 people over a single year, so it establishes that the drug moves both inflammation and scarring while the larger phase 3 confirmation and long-term outcome data are still being gathered. Gastrointestinal effects such as nausea were the most common events, mostly mild to moderate. It is a drug that comes after the habits, and it was studied alongside standard lifestyle advice.

Over 6 years of follow-up, people who drank sugar-sweetened beverages more often had higher odds of new and prevalent fatty liver than those who rarely did, with the risk rising as intake rose. Measured in: Adults in the Framingham Heart Study Offspring and Third Generation cohorts, followed with liver fat assessed by CT and diet by questionnaire. What could explain it instead: People who drink a lot of sugary beverages tend to eat more calories overall, weigh more, and move less, and those factors also cause fatty liver, so part of the association reflects the whole dietary and lifestyle pattern, not the drink in isolation.. An observational cohort, so it shows that sugary-drink intake travels with fatty liver, not that it is the sole cause. Diet soda, by contrast, was not clearly protective, which fits the idea that the surrounding diet and body weight carry much of the signal.

Pooling randomized trials, berberine improved liver enzymes, reduced liver fat, and improved insulin resistance and blood lipids compared with control, often alongside lifestyle advice. Measured in: Meta-analysis of randomized controlled trials of berberine in adults with non-alcoholic fatty liver disease. The trials are mostly small, short, and run in China with varied quality and dosing, so the pooled benefit is promising, not settled, and long-term and biopsy outcomes are missing. Berberine can lower blood sugar and interacts with several medications, so it belongs with a practitioner, not self-stacked. It is the active compound in Coptis (Huang Lian), a bitter cold herb Chinese medicine uses to clear damp-heat, which fits the robust, inflamed presentation and not the tired, Spleen-deficient one.

Pooling randomized trials, silymarin modestly lowered the liver enzymes ALT and AST compared with control, with smaller and less consistent effects on liver fat itself. Measured in: Systematic review and meta-analysis of randomized controlled trials of silymarin in people with non-alcoholic fatty liver disease or steatohepatitis. The effect on enzymes is modest, and enzymes are a rough marker, not proof the underlying disease is reversing; the harder outcomes, inflammation and fibrosis on biopsy, are not established. Milk thistle has a long traditional record for the liver and a good safety profile, which is part of why it keeps being studied; it is a reasonable adjunct, not a replacement for the weight, diet and activity work.