Non-alcoholic fatty liver disease (NAFLD) and fatty liver hepatitis (NASH) are very common in the Western world and strongly associated with obesity. No known effective treatment is known. From animal studies, it is known that the compound resveratrol perhaps has the potential to neutralize obesity-induced diseases. Resveratrol is already widely used as a food supplement though the precise effects are unknown. This project focuses on the effect of Resveratrol on fatty liver disease. The researchers plan to investigate the effects of Resveratrol or placebo treatment for 6 months on NAFLD/NASH in obese patients.