Certain probiotic strains such as Bacillus coagulans, Bifidobacterium animalis subsp. lactis BB-12, Escherichia coli Nissle 1917, and multispecies probiotic mixtures have shown evidence of helping with digestive problems, particularly in functional dyspepsia and irritable bowel syndrome (IBS).
What the research shows
High-quality randomized controlled trials support the use of Bacillus coagulans MY01 and Bacillus subtilis MY02 for functional dyspepsia, showing improved symptoms and safety. For IBS, multispecies probiotics including Bifidobacterium animalis subsp. lactis BB-12, Lactobacillus rhamnosus GG, and others have demonstrated symptom relief and microbiota stabilization. Escherichia coli Nissle 1917 showed benefits mainly in IBS patients with prior gastroenteritis or antibiotic use. Lactobacillus casei GG showed no significant overall benefit but may help diarrhea-predominant IBS. Lactiplantibacillus plantarum 299v did not show significant efficacy in IBS. Some probiotic mixtures containing Lactobacillus rhamnosus GG and others also showed symptom improvement in IBS. Evidence for probiotics in dyspepsia related to Helicobacter pylori is low and mainly theoretical. Safety profiles across studies were generally good with no significant adverse events. Limitations include small sample sizes in some studies, heterogeneity of probiotic strains and IBS subtypes, and the need for more large-scale, blinded trials.
Best studied probiotic strains
Bacillus coagulans MY01 and Bacillus subtilis MY02
Effective in functional dyspepsia; may modulate immune and microbial factors.
Bifidobacterium animalis subsp. lactis BB-12 (part of multispecies probiotic)
Used in combination with other strains; benefits IBS symptoms.
Escherichia coli Nissle 1917
May be more effective in IBS subgroups with altered gut flora.
Lactobacillus rhamnosus GG (part of probiotic mixtures)
Often used in combination with other strains; benefits IBS symptoms.
Who may benefit
Safety
Probiotics studied were generally safe and well tolerated with adverse event rates similar to placebo. Serious adverse events were rare and unlikely related to probiotic use.
Limitations
Some studies had small sample sizes or open-label designs. Effects may vary by probiotic strain and patient subgroup. More large-scale, double-blind, placebo-controlled trials are needed to confirm findings and clarify optimal strains and doses. Evidence for probiotics in Helicobacter pylori-associated dyspepsia is limited and mostly theoretical.
PubMed sources
| Study | Type | Year | PMID |
|---|---|---|---|
| Efficacy and safety of spore-forming probiotics in the treatment of functional dyspepsia: a pilot randomised, double-blind, placebo-controlled trial. The lancet. Gastroenterology & hepatology |
Randomized Controlled Trial | 2021 | 34358486 |
| Systematic review: Complementary and alternative medicine in the irritable bowel syndrome. Alimentary pharmacology & therapeutics |
Systematic Review | 2006 | 16441466 |
| Clinical trial: multispecies probiotic supplementation alleviates the symptoms of irritable bowel syndrome and stabilizes intestinal microbiota. Alimentary pharmacology & therapeutics |
Randomized Controlled Trial | 2008 | 17919270 |
| Therapeutic Role of Probiotics for the Treatment of Dyspepsia: A Review of the Literature. Neurogastroenterology and motility |
Research Study | 2025 | 40342291 |
| A double-blind placebo-controlled trial to study therapeutic effects of probiotic Escherichia coli Nissle 1917 in subgroups of patients with irritable bowel syndrome. International journal of colorectal disease |
Randomized Controlled Trial | 2012 | 22130826 |
| A probiotic mixture alleviates symptoms in irritable bowel syndrome patients: a controlled 6-month intervention. Alimentary pharmacology & therapeutics |
Randomized Controlled Trial | 2005 | 16128676 |
| Bacterial supplementation in the irritable bowel syndrome. A randomised double-blind placebo-controlled crossover study. Digestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver |
Randomized Controlled Trial | 2000 | 11515626 |
| Fermented milk containing Bifidobacterium lactis DN-173 010 improved self-reported digestive comfort amongst a general population of adults. A randomized, open-label, controlled, pilot study. Journal of digestive diseases |
Randomized Controlled Trial | 2009 | 19236549 |
| Effects of symbiotic preparations on constipated irritable bowel syndrome symptoms. Acta bio-medica : Atenei Parmensis |
Clinical Trial | 2007 | 17933278 |
| Role of Lactobacillus plantarum 299v versus Placebo in symptomatic improvement of irritable bowel syndrome patients. JPMA. The Journal of the Pakistan Medical Association |
Randomized Controlled Trial | 2022 | 35320214 |