The purpose of this study is to investigate the effects of the antioxidant "resveratrol" on liver fat content, body-composition and insulin sensitivity

Resveratrol is found in grape skin, wine, peanuts, and mulberries and is thought to have health benefits such as improving fat metabolism, insulin action, and possibly extending lifespan. resVida™ is the name for the dietary supplement containing the natural antioxidant "resveratrol". resVida™ will be supplied by DSM Nutritional Products, Ltd.

resVida™ is considered a dietary supplement, and therefore it is not an approved drug by German Authority. It is regulated like a food. The makers of resVida™ make no claim that this supplement is meant to treat any ailment.

This study is designed to investigate the health benefits of resveratrol.

Inclusion Criteria:

• Gender: male and female
• Age: 18 years - 70 years (inclusive)
• Overweight and obese (BMI ≥>27 mg/kg2)
• HOMA-IR ≥>2.0
• Negative urine pregnancy test
• Acceptable to be taking the oral contraceptive pill or other methods of birth control (surgical sterility, double barrier methods, intrauterine contraceptive device, lifestyle with a personal choice of abstinence, vasectomy of sexual partner at least 3 months prior to enrolment in combination with barrier methods)
• Willingness and ability to give written informed consent and willingness and ability to understand, to participate and to comply with the study requirements.

Exclusion Criteria:

• Subjects who have liver cirrhosis
• Subjects with a further liver disease diagnosis (e.g. known M. Wilson, autoimmune hepatitis, primary sclerosing cholangitis)
• Subjects who were diagnosed with diabetes
• Current pregnancy or breast feeding (as determined by a pregnancy test); postmenopausal women taking oral hormone therapy.
• Delivery within the last year
• Changes in the dose or initiation of lipid altering medication within the preceding three months, such as statins, fibrates or systemic steroids
• Significant co-morbid inflammatory illnesses as as rheumatoid arthritis, chronic bowel disease, sarkoidosis etc.
• Contraindications to MR scanning - claustrophobia, cardiac pacemaker, ferromagnetic haemostatic clips in the central nervous system, metallic splinters in the eye, automatic cardioverter defibrillators, prosthetic heart valves, cochlear implants, insulin pumps and nerve stimulators, etc. or who do not fit into the MR machine due to severe adiposity
• Subjects with any medical condition that is judged by the investigators to be likely to interfere with the evaluation of the subject's safety and of the study outcome.
• Subjects with abnormalities in the safety profile judged by the investigators to be clinically significant.
• Subjects with ALT or AST > 2.5x of the upper reference limit (50 U/L respectively)
• Subjects on treatment with drugs that are strongly metabolized via CYP3A4 (e.g. alfentanil, astemizole, cisapride, cyclosporine, diergotamine, ergotamine, fentanyl, irinotecan, pimozide, quinidine, sirolimus, tacrolimus, terfenadine) and CYP2C9 (e.g. Phenytoin and Warfarin)
• Smokers (> 10 cigarettes per day)
• Regular drinkers of more than15g /day (e.g wine (0,1 l), 1 beer (0,33 l)
• History of, or current evidence of, abuse of alcohol or any drug substance, licit or illicit.
• Intake of over-the-counter (OTC) medication or any dietary supplement (except occasional paracetamol/aspirin, and multivitamin supplements) for the duration of the study.
• Poor compliers or subjects unlikely to attend.
• Receipt of any investigational products (e.g., drugs, supplements, dietary interventions) as part of a research study within 30 days of initial dose administration in this study.
• Blood donation (usually 550 ml) within the 12 week period before the initial study dose.