Effect of Bacillus subtilis ATCC 122264 on intestinal gas symptoms and quality of life in adults with functional bloating

Probiotics can confer a beneficial effect on gastrointestinal-related symptoms and their impact on daily life. This randomised, double-blind, placebo-controlled study assessed the efficacy of a novel probiotic strain Bacillus subtilis ATCC 122264 as a probiotic on gas-related symptoms in healthy adults. One hundred healthy adults with functional bloating/distension according to the ROME IV criteria, were randomised in a 1:1 ratio to receive either 5 billion cfu of B. subtilis) or placebo daily for 8 weeks. Intestinal gas symptoms and impact on daily life were assessed weekly by the 17-item Intestinal Gas Questionnaire (IGQ) and the change from baseline was analysed by ANCOVA at 4 and 8 weeks. Post-hoc analyses were conducted on the two parts of the IGQ, scored separately. Sub-group analyses based on sex were also done on the IGQ global and dimension scores as well as the scores from the two individual parts of the IGQ. Safety was assessed by reports of adverse events. B. subtilis did not differ from placebo in the change from baseline to Weeks 4 or 8 in IGQ global score or dimension scores of bloating, flatulence, belching, bad breath, stomach rumbling and difficult gas evacuation ( P > 0.05). In females taking B. subtilis, the severity of belching and flatulence significantly decreased after 4 ( P = 0.046) and 8 weeks ( P = 0.039) respectively, compared to females taking placebo. The impact of flatulence on daily life decreased after 8 weeks in females taking B. subtilis compared to placebo ( P = 0.03). B. subtilis was safe and well tolerated over the 8-week study period. The results suggest that B. subtilis may reduce gas-related symptoms, such as bloating and flatulence, in females. Further studies are needed to confirm the sex-related effects of B. subtilis in populations with gastrointestinal symptoms. Registered at Clinicaltrials.gov: NCT06308146.