The investigators aim to test the hypothesis that Lactobacillus Reuteri-enriched microbiota improves insulin sensitivity and glucose tolerance in obese healthy and obese type 2 diabetes patients by improving gut hormone secretion and compare these findings to healthy lean subjects.
Inclusion Criteria: * Obese subjects: age 40 - 65 years, obesity (BMI 30-45 kg/m2), non-smoking, absence of gastrointestinal disease, willingness to abstain from intake of fermented milk products over a study period of 8 weeks. * Healthy control subjects: non-obese (BMI 19-25 kg/m2), non-diabetic subjects, matched for age and sex, non-smoking, absence of gastrointestinal disease, willingness to abstain from intake of fermented milk products over a study period of 8 weeks. Exclusion Criteria: * pregnancy, cancer, chronic diseases, antibiotic therapy, competitive athletes.