Abstract
Background: Bloating, gas, and abdominal discomfort are common in healthy individuals but lack effective interventions. Probiotics can alleviate some gastrointestinal (GI) symptoms; however, evidence for their impact on bloating, gas and abdominal discomfort in otherwise healthy populations remains limited. Mechanistic studies suggest that synbiotics may influence the underlying mechanisms of bloating, including increased gas production, impaired gut motility, and visceral hypersensitivity, but there is a paucity of data from large trials evaluating clinical outcomes. Accordingly, we evaluated the effects of a multi-species synbiotic on GI symptoms. Methods: In a randomized, double-blind, placebo-controlled, decentralized trial, participants (n = 350) with self-reported bloating/indigestion received either a multi-species synbiotic (53.6 billion AFU multi-species probiotic and 400 mg pomegranate extract; DS-01) or placebo daily for 6 weeks. Outcomes included GI quality-of-life (DQLQ), bloating and gas (PROMIS-GI 13a), abdominal discomfort (PROMIS-GI 5a), constipation, regularity, mood-related symptoms, and safety. Results: The multi-species synbiotic improved GI quality-of-life compared to placebo (0.80 vs. 1.20; p < 0.05) at Week 6. Bloating and gas were reduced in the synbiotic arm compared to placebo (16.0 vs. 21.0; p < 0.01), with more participants reporting never/rarely bloating (72.3% vs. 55.9%; p < 0.001). Abdominal discomfort also decreased (8.0 vs. 10.0; p < 0.01). Additionally, there was a statistically significant improvement in constipation symptoms and regularity in the synbiotic arm relative to placebo. Conclusions: Daily supplementation with this multi-species synbiotic significantly improved GI quality-of-life, bloating, gas, abdominal discomfort, and bowel habits. This is the first synbiotic to demonstrate meaningful improvements in bloating and gas in a generally healthy, diverse, real-world population.