Effects of Fructose Restriction on Liver Steatosis

Inclusion Criteria: * Age ≥ 18 years * Body mass index ≥ 28 kg/m2 * Fatty liver index ≥ 60 * Fructose intake ≥45 grams/day Exclusion Criteria: * Medical history of liver disease * (History of) excessive alcohol consumption (defined as \> 2 units/day for women, and \> 3 units/day for men) * Major change in weight and/or physical activity prior to the study * Use of glucose lowering drugs * Recent illness * Pregnancy and/or lactation * Contraindications for magnetic resonance imaging * Inability to give informed consent Protocol change (implemented on July 18, 2018): in order to increase the inclusion of study participants, subjects with an average daily fructose intake \< 45 gram/day will also be eligible for participation. In subjects who have an average daily fructose intake \< 45 gram/day, supplementation of either fructose or glucose (see 'Arms and Interventions') will be increased to 45 gram/day.