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  • Writer's pictureKaren

Which Probiotic Strains Are Effective For Treating IBS?

Updated: Jan 29, 2022


Irritable bowel syndrome (IBS) is characterized by recurrent abdominal pain, bloating, and changes in bowel habits, which may include diarrhea- or constipation-predominant symptoms. Treatment guidelines for IBS recommend the use of probiotics,[1] but choosing an appropriate supplement can be challenging due to the diversity of available probiotics, the unique efficacy of different strains, and the lack of randomized controlled trials for some strains.

The study

This meta-analysis of 40 randomized controlled trials examined which probiotic strains are effective for the treatment of IBS in more than 3,000 participants. The primary outcomes were change in the global IBS-Symptom Severity Score, improvement of global IBS symptoms reported by a physician or participant interview/diaries, change in abdominal pain scores, frequency of reporting abdominal pain relief, change in bloating scores, and change in quality-of-life scores. The secondary outcome was the number and types of adverse reactions.

The results

The dosage of the probiotic was typically 1x109–1x1010 CFU/day for 4–8 weeks. There were no significant differences in the frequency or types of adverse reactions in the probiotic and placebo groups.

The following probiotics reduced the global IBS-Symptom Severity Score in at least 2 studies:

  • Bifidobacterium infantis 35624

  • Bacillus coagulans MTCC5260

  • A 7-strain mixture of Bifidobacterium brevis 11858BP, Bifidobacterium lactis 11903BP, Bifidobacterium longum 11860BP, Lactobacillus