Lactobacillus plantarum
Lactobacillus plantarum, now named Lactiplantibacillus plantarum, is a lactic acid bacterium common in fermented plant foods such as sauerkraut, kimchi and sourdough.
Can 299v help irritable bowel syndrome (IBS)?
A 2026 strain-specific meta-analysis included six studies of 299v. Pooled results favored it for abdominal-pain severity and feelings of incomplete evacuation, but not for constipation resolution or the severity of bloating and flatulence. Some symptom-improvement rates were positive even where severity scores were not, and results varied substantially between trials. 1
299v is a reasonable research lead for some IBS symptoms, especially pain. It is not a uniform answer to every digestive complaint, and the findings do not cover all plantarum products. 1
A different strain for chronic diarrhea
A small trial reported results for 55 adults with chronic diarrhea after about four weeks of CCFM1143 at 3.52 billion CFU daily. Stool frequency and consistency improved, while quality of life and stool satisfaction did not improve significantly. The methods describe 90 initially randomized patients, so the smaller reported sample also matters when interpreting the result. 2
Does DR7 reduce respiratory symptoms?
In a 12-week trial involving 109 adults, DR7 at one billion CFU daily reduced some measures of upper respiratory illness, including days with nasal symptoms. Immune-marker changes were also observed. A later paper reanalyzed the same trial to address limitations; it is not an independent replication. 3 4
The findings justify more research on DR7 and respiratory symptoms. They do not establish a general immune benefit for every plantarum strain. 3 4
What about the gut–brain connection?
A three-week study assigned 60 students with exam-related anxiety to JYLP-326 or placebo and included a separate non-anxious comparison group. Symptom scores for anxiety, depression and insomnia improved with the probiotic, while stool microbes and metabolites also changed. The study concerned a specific exam-stress setting, not established treatment of psychiatric disorders. 5
This keeps a useful gut–brain hypothesis open. The associated microbiome changes do not prove the mechanism or show that another strain would have the same effect. 5
A probiotic is one option, not the whole IBS plan
IQWiG describes evidence for several approaches to IBS, including enteric-coated peppermint oil, some antispasmodic medicines, psychological therapies and physical activity. Studies are too different to rank these options reliably against one another. The choice depends on the symptoms and the burdens of each approach. 6
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Gut Health4 effects
No study is linked to this rating.
No study is linked to this rating.
Immune Support1 effect
Other effects3 effects
No study is linked to this rating.
All studies
14 publications are linked to Lactobacillus plantarum, newest first.