Effects of Probiotic Use on Gastrointestinal Symptoms in the Late Postoperative Period of Bariatric Surgery: A Cross-Over, Randomized, Triple-Blind, Placebo-Controlled Study

Despite the benefits associated with weight reduction, the anatomical and functional changes of bariatric surgery may favor the development of undesirable side effects such as the appearance of gastrointestinal symptoms (GIS). The aim of this study was to evaluate the effects of using probiotics in individuals with GIS 1 year after being submitted to Roux-en-Y Gastric Bypass (RYGB).

This is an experimental, prospective, randomized, cross-over, triple-blind, placebo-controlled study, carried out with patients 1 year after being submitted to RYGB and who reported at least one moderate GIS. Subjects were randomized into two groups and completed the two research periods: in one they received placebo capsules, in the other 50 billion CFU of probiotics (Lactobacillus acidophilus, Bifidobacterium lactis, Lactobacillus rhamnosus, Bifidobacterium longum, Lactobacillus plantarum, Bifidobacterium bifidum and Lactobacillus gasseri), both for 8 weeks, with 8 weeks of wash-out period in between, and were evaluated for the presence of Small Intestine Bacterial Overgrowth (SIBO) and GIS, through the Hydrogen breath test and Gastric Symptom Rating Scale (GSRS) questionnaire.

Of a total of 56 participants, 47 individuals completed the study. No significant effects were observed in neither the gastrointestinal symptoms or in the prevalence of SIBO with the use of probiotics.

Supplementation of the probiotics chosen for this study does not seem to alleviate GIS or influence the improvement of SIBO in symptomatic patients after 1 year of RYGB.