Bifidobacterium lactis MAK16B42L and Improved Bowel Movement Frequency

Research synthesisLow evidenceModerate effect3 studies · 3 beneficial · 0 neutral · 0 harmful

Across 3 randomized controlled trials, all reported beneficial moderate-sized effects of Bifidobacterium lactis strains on bowel movement frequency. Two of the three studies found statistically significant increases in defecation frequency compared to placebo, primarily in adults with low bowel movement frequency or functional constipation. The available evidence suggests a consistent benefit, but the evidence base is small and preliminary.

Studied populations: Adults with low defecation frequency and abdominal discomfort; adults with functional constipation

Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed).

Generated May 12, 2026

3 of 3 papersPopulation:

Effect of the probiotic strain Bifidobacterium animalis subsp. lactis, BB-12®, on defecation frequency in healthy subjects with low defecation frequency and abdominal discomfort: a randomised, double-blind, placebo-controlled, parallel-group trial
- 2015-09-18
- RCT · n = 1,248
- British Journal of Nutrition 114(10)
- - D. Eskesen
  - L. Jespersen
  - B. Michelsen
  - P. Whorwell
  - S. Müller-lissner
  - Cathrine M Morberg
- PubMed: 26382580
- DOI: 10.1017/S0007114515003347
9 Insights on
- Improved Bowel Movement Frequency
- High evidence
- Large Human Trial
- Clinical
A treatment effect on average defecation frequency was found (P=0·0065), with the frequency being significantly higher compared with placebo at all weeks for probiotic treatment overall (all P<0·05).
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Effects of 28-day Bifidobacterium animalis subsp. lactis HN019 supplementation on colonic transit time and gastrointestinal symptoms in adults with functional constipation: A double-blind, randomized, placebo-controlled, and dose-ranging trial
- 2018-02-08
- RCT · n = 228
- Gut Microbes 9(3)
- - A. Ibarra
  - Mathilde Latreille-Barbier
  - Y. Donazzolo
  - X. Pelletier
  - A. Ouwehand
- PubMed: 29227175
- DOI: 10.1080/19490976.2017.1412908
22 Insights on
- Improved Bowel Movement Frequency
- High evidence
- Rigorous Journal
- Clinical
A post hoc analysis of 65 participants with fewer than 3 bowel movements per week (BMF ≤ 3/week) showed a physiologically relevant increase in weekly BMF in the high- (+2.0) and low-dose (+1.7) HN019 groups-by RMANOVA, the HN019 groups with BMF ≤ 3/week, pooled together, had a higher BMF versus placebo (P value = 0.01).
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Dose
1 × 10^9 CFU/day or 1 × 10^10 CFU/day (pooled analysis in subgroup with BMF ≤ 3/week)
Effects of administration of Bifidobacterium animalis subsp. lactis GCL2505 on defecation frequency and bifidobacterial microbiota composition in humans.
- 2012-05
- RCT · n = 17
- Journal of Bioscience and Bioengineering 113(5)
- - Akihiro Ishizuka
  - K. Tomizuka
  - Ryo Aoki
  - Tomohiko Nishijima
  - Yasuo Saito
  - R. Inoue
  - K. Ushida
  - Takashi Mawatari
  - Takayuki Ikeda
- PubMed: 22284965
- DOI: 10.1016/j.jbiosc.2011.12.016
21 Insights on
- Improved Bowel Movement Frequency
- High evidence
In addition, the defecation frequency increased during GCL2505 administration compared with the placebo.
Effect
Beneficial
Effect size
Moderate

Bifidobacterium lactis MAK16B42L and Improved Bowel Movement Frequency

Effect of the probiotic strain Bifidobacterium animalis subsp. lactis, BB-12®, on defecation frequency in healthy subjects with low defecation frequency and abdominal discomfort: a randomised, double-blind, placebo-controlled, parallel-group trial

Effects of 28-day Bifidobacterium animalis subsp. lactis HN019 supplementation on colonic transit time and gastrointestinal symptoms in adults with functional constipation: A double-blind, randomized, placebo-controlled, and dose-ranging trial

Effects of administration of Bifidobacterium animalis subsp. lactis GCL2505 on defecation frequency and bifidobacterial microbiota composition in humans.