Efficacy and Safety of Intake of Bifidobacterium breve N708-containing Food on Diarrhea Due to Stress-Randomized Double-blind, Placebo-controlled, Parallel-group Comparison Study-

Background　To investigate the effects of ingestion of Bifidobacterium breve N708（N708）-containing foods on diarrhea deu to stress, a randomized, double-blind, placebo-controlled, parallel-group controlled trial was conducted in healthy Japanese individuals（ages 20-65 years）with daily stress and diarrhea with abdominal pain and discomfort. Methods　Subjects（n＝70）ingested heat sterilized N708-containing foods（N708 group; n＝35）or placebo foods（placebo group; n＝35）for 8 weeks. Efficacy was assessed by defection questionnaires, Izumo scale, POMS2 shortened version, serum cytokines［interleukin（IL）-6, IL-10, and tumor necrosis factor（TNF）-α］, fecal mucins, and IgAs. The values of the items were compared between the N708 and the placebo groups by Mann-Whitney U-test, Studentʼst-test, or Welch t test. Results　Izumo scale score of Question 7（“Are you bothered by early satuation?”）and Question 8（“Are you bothered by post-prandial long-lasting epigastric fullness or nausea?”）related to abdominal fullness were significantly improved in the N708 group compared to the placebo group（P＜0.05）. No significant differences were observed between the groups for the other items. A subgroup analysis of 20 subjects with higher scores for diarrheal symptoms at the screening showed that the change in scores in the N708 group was significantly improved（P＜0.05）for Question 15（“Are you bothered by stress-related diarrhea?”）on Izumo scale related to stress diarrhea compared to the placebo group. Although there were some differences in safety among multiple items, they were all within standard values and were also considered to be within the range of physiological fluctuations due to lifestyle and habits. Conclusions　Our results suggest that ingestion of N708 is safe and improves stress-induced diarrhea in subjects with higher scores for diarrheal symptoms. （UMI34571）