Overview

The recommended treatment for metabolic dysfunction-associated steatotic liver disease (MASLD) currently focuses on lifestyle changes, including dietary adjustments and increased physical activity. Intermittent fasting is a specific dietary approach in which food intake is restricted for certain periods. Recent scientific evidence suggests that intermittent fasting can positively influence body weight, insulin resistance, and markers of inflammation.

This study will examine whether restricting energy intake to approximately 600 kcal on two days per week has beneficial effects on MASLD. The nutritional framework is based on the guidelines of the German Nutrition Society (DGE) for a healthy diet (10 rules for healthy eating). Following a two-week introduction to these DGE recommendations, participants will be randomly assigned to one of two treatment groups.

In the intervention group, participants follow a 5:2 intermittent fasting regimen, eating without restrictions on five days per week and limiting intake to about one-quarter of their usual daily energy (≈600 kcal) on two non-consecutive days. In the control group, participants follow a healthy diet according to DGE guidelines without restrictions on timing or energy intake.

Eligibility

Inclusion Criteria:

• 18 and 75 years
• Body mass index (BMI) \> 25 kg/m²
• MASLD grade 3 with CAP ≥ 280 dB/m, excluding liver damage
• Liver stiffness \< 13 kPa
• Ability to understand the study and the individual consequences of participating in the study
• Signed and dated consent form before the start of any study activity

Exclusion Criteria:

• Hepatocellular carcinoma or non-curatively treated carcinomas
• Alcohol consumption \>20 g (women) and \>30 g (men) per day
• Other liver diseases (HBV, HCV, HDV, HEV, HIV), autoimmune diseases or chronic cholestatic liver disease, hereditary haemochromatosis, Wilson's disease, α-1-antitrypsin deficiency
• Medications that cause liver disease or secondary NAFLD (e.g. tamoxifen, systemic corticosteroids, methotrexate, tetracyclines, oestrogens, valproic acid)
• Body weight changes of \> 5% in the last 6 months
• Statins and/or other lipid-lowering drugs, if these have not been taken in a stable dose for at least 4 weeks
• Uncontrolled type 2 diabetes defined as HbA1c value \> 9.0% or insulin-dependent type 2 diabetes
• Pregnancy
• Immunological or inflammatory diseases (e.g. systemic lupus erythematosus)
• Following a restrictive, special diet
• Patients who have undergone organ transplants
• Lack of or absence of capacity to give consent