What the Evidence Says About Lactobacillus plantarum 299v and Gas/Bloating

The short answer is: the evidence for reducing gas production is weak, and the results for bloating are mixed.

Gas Production (Flatulence)

Pillser's research database contains 1 clinical trial specifically looking at gas production¹. In that study:

• Participants on placebo had a median maximum gas production rate of 0.55 ml/min.
• Participants on Lp299v had a median maximum gas production rate of 0.92 ml/min.
• The difference was not statistically significant.

So the only direct measurement of gas production found no benefit — and actually showed a trend toward slightly more gas on the probiotic, though this wasn't significant.

Bloating (Related but Distinct)

Bloating is a common companion to excess gas, and the data here is mixed²:

• 1 study (2001) reported that Lp299v decreased abdominal bloating in patients with irritable bowel disease, showing a moderate beneficial effect.
• 1 larger RCT (2022, n=190) found no significant difference between Lp299v and placebo for relieving bloating in IBS patients.

Bottom Line

Outcome	Studies	Verdict
Gas production	1 study	❌ No significant benefit
Bloating	2 studies (1 beneficial, 1 neutral)	⚖️ Mixed — older study showed benefit, but a more recent larger trial found none

Based on the available evidence, Lp299v does not appear to reliably reduce gas production. For bloating, the results are inconsistent, and the most recent and largest trial suggests no meaningful benefit over placebo.

Footnotes

1. Pillser research database, Lactobacillus plantarum 299v and Reduced Gas Production — 1 study, neutral effect. ↩

2. Pillser research database, Lactobacillus plantarum 299v and Reduced Bloating — 2 studies, 1 beneficial and 1 neutral. ↩