Inclusion Criteria:  White men and women between 18 and 65 years of age. BMI range between 25 and 40 kg/m2 Absence of underlying pathology in medical and physical examination, except for those related to excess weight. Signature of the informed consent for participation in the study.  Exclusion Criteria:  Serious systemic disease not related to obesity, such as cancer, kidney or severe liver disease. Systemic diseases with intrinsic inflammatory activity (autoimmune diseases such as rheumatoid arthritis and asthma) Pregnancy and lactation. Vegetarians or subjects subjected to an irregular diet. Patients with severe eating disorders. Patients with clinical symptoms and signs of infection in the previous month. Patients with chronic anti-inflammatory steroid treatments and/or nonsteroidal anti-inflammatory drugs. Recent antibiotic treatment. Psychiatric history. Uncontrolled alcoholism or drug abuse.