Effects of Caloric Restriction in Obesity and Type 2 Diabetes

Inclusion Criteria * Age \>40 years; * Type 2 diabetes (ADA criteria); * UAE \<300 mg/24h; * Body mass index (BMI)\>27kg/m2; * Serum creatinine \< 1.2 mg/dL; * No major changes in calorie, protein and sodium intake in the last 6 mos; * No major changes in concomitant treatments with blood pressure, glucose or lipid lowering agents since 6 and 3 months respectively; * Patients legally able to give written informed consent to the trial (signed and dated by the patient); * Written informed consent. Exclusion Criteria * Concomitant non-diabetic renal disease or ischemic kidney disease; * Primary or immune-mediated renal disease; * Urinary tract obstruction or infection; * Treatment with steroids and/or non-steroid anti-inflammatory agents; * Treatment with thiazide or loop diuretics that, on the basis of the Investigator's judgment, might sustain hypovolemia and/or sodium depletion (with secondary kidney hypoperfusion/hypofiltration); * Hearth failure and/or hemodynamically significant left ventricular systolic dysfunction, cirrhosis, uncontrolled hyperglycemia resulting in glycosuria, hyper/hyponatremia of any cause; * Previous surgical procedures for weight loss; * Previous episodes of depression, or suicide attempts; * Chronic abuse of alcohol and drugs; * Pregnancy, ineffective contraception or peri-menopausal age; * Cancer or any chronic disease that might affect the completion of the study; * Chronic obstructive pulmonary disease (COPD) in treatment with positive airway pressure; * Unwillingness or inability to adhere to CR intervention over the entire 24-months intervention period; * Legal incapacity and/or other circumstances rendering the patient unable to understand the nature, scope and possible consequence of the trial; * Evidence of an uncooperative attitude; * Any evidence that patient will not be able to complete the trial follow-up; * Inability to fully understand the potential risks and benefits of the study.