The Copenhagen Insulin and Metformin Therapy Trial

Inclusion Criteria: * Males and females over 30 years of age * Type 2 diabetes * Body mass index (BMI): 25.0-39.9 kg/m2 * HbA1c above 7.5 % * Antidiabetic tablet-treatment during 1 year minimum AND / OR * Insulin treatment during a minimum of 3 months * Negative pregnancy test * Signed, informed consent Exclusion Criteria: * MI, coronary revascularization, TCI,or apoplexy within the last 3 months * TCI with verified stenosis of above 70% * Heart failure (NYHA class III or IV) * Former cancer patient, unless disease-free period of more than 5 years * estimated creatinine clearance \< 60 ml/min Liver disease * Alcohol abuse * Drug abuse * Retinopathy with on-going laser treatment at start of study * Other acute or chronic serious disease leading to hypoxia * Pregnant or breastfeeding women * Women of child-bearing potential, not using contraceptives * Allergy to medication used in the study * Incapable of understanding the nature of the informed consent