The investigators aim to show that SGLT2 inhibition decreases liver fat whereas we aim to demonstrate why liver fat remains unchanged in humans, treated with metformin. These data will provide the first evidence for the use SGLT2 inhibitors in NAFLD, and will be highly informative for the design of future clinical studies. Moreover, the data gained from the metformin arm of the study will provide the first mechanistic evidence in humans of the effects of metformin on hepatic fatty acid metabolism.