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Randomized trial · measured other health measures

6-week trial in 44 adults: probiotic did not clearly change bowel symptoms or anxiety

Pinto-Sanchez and colleagues · Gastroenterology · 2017

Original title: Probiotic Bifidobacterium longum NCC3001 Reduces Depression Scores and Alters Brain Activity: A Pilot Study in Patients With Irritable Bowel Syndrome.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

No difference

14 of 22 patients on the probiotic had lower depression scores vs 7 of 22 on placebo (P = .04). The probiotic had no significant effect on anxiety or IBS symptoms.

The study at a glance

Type of study
Randomized trial
Who or what was studied
44 people · 44 adults with IBS (diarrhea or mixed) and mild to moderate anxiety or low mood
What was tested
Bifidobacterium longum NCC3001 daily vs placebo for 6 weeks
What it measured
Several kinds of outcomes
How long
6 weeks
Trial registration
NCT01276626
Who has a stake
No disclosure in PubMed
No disclosure in PubMed.
Journal
Gastroenterology, 2017
Source
PubMed record 28483500. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • ✓Compared with a placebo, a dummy treatment.
  • –Small: 44 people. Small trials can miss real effects or find chance ones.
  • –Short: 6 weeks. Longer-term effects are unknown.
  • •Measured several kinds of outcomes.
  • •The PubMed record has no conflict-of-interest statement.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: gut symptoms such as bloating and IBS

    9

    5 benefit, 2 mixed, 2 no difference

  2. Trials in people: other measures

    10

    4 benefit, 2 mixed, 4 no difference

    ↑ This study is the ringed dot

  3. Trials in people: lab tests or safety

    0

    None among the papers we read.

  4. Population studies

    0

    None among the papers we read.

  5. Blood levels and genes

    0

    None among the papers we read.

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Do probiotics improve gut health?”

Some strains may help some symptoms.

Confidence: low. Based on 28 on-topic papers.

Read the full answer

Of the other 9 papers on the same step: 4 benefit, 2 mixed, 3 no difference. This one found no difference.

Other papers on the same step

See all 28 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The reviewer corrected 1 field after reading the abstract. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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