Patients will be randomized into two groups: control group to receive placebo (polydextrose - 12 g / day) and synbiotic group - group supplemented with synbiotic (fructo-oligosaccharide and probiotics - 12 g / day). Probiotics are: Lactobacillus acidophilus; Lactobacillus rhamnosus; Lactobacillus paracasei; Bifïdobacterium lactis.