Bifidobacterium animalis subsp. lactis BB-12 and Reduced Upper Respiratory Infections

Research synthesisModerate evidenceModerate effect6 studies · 5 beneficial · 1 neutral · 0 harmful

Across 5 of 6 studies, BB-12 shows beneficial effects on reducing upper respiratory infections, with effect sizes ranging from small to large; the predominant effect size is moderate. Evidence includes one meta-analysis and several RCTs, with the most consistent benefit observed in healthy infants and young children. Doses were not consistently reported, but one study used 10 billion CFU/day.

Effective dose range: 10 billion CFU/day (based on one study; other studies did not report dose)
Studied populations: Healthy infants, young children aged 0-3 years, and children in early childhood education settings

Caveats: One of the 6 studies (a 2026 RCT in children in early childhood education) found a neutral effect, introducing some inconsistency. The evidence includes a meta-analysis from 2025 and RCTs, but the total number of studies is small (6), and one review had limited methodological detail. 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 Jun 17, 2026

Doses used in studies

CFU/day: 10 billion (median 10 billion, IQR 10 billion–10 billion) — 1 study

6 of 6 papersPopulation:

Bifidobacterium animalis subsp. lactis BB-12 in reducing the risk of infections in early childhood
- 2015-09-15
- RCT · n = 109
- Pediatric Research 79(1)
- - T. Taipale
  - K. Pienihäkkinen
  - E. Isolauri
  - J. Jokela
  - E. Söderling
- PubMed: 26372517
- DOI: 10.1038/pr.2015.174
6 Insights on
- Reduced Upper Respiratory Infections
- High evidence
- Infants
The infants receiving BB-12 were reported to have experienced fewer respiratory tract infections (RTIs; 87 vs. 100%; risk ratio: 0.87; 95% confidence interval: 0.76, 1.00; P = 0.033) than the controls.
Effect
Beneficial
Effect size
Small
Significant
Yes
Dose
10 billion colony-forming units/day
Comparative effectiveness of oral nutritional supplements in preventing respiratory tract infections among adults: a systematic review and network meta-analysis.
- 2025-10
- Meta-Analysis · n = 751
- EClinicalMedicine 88
- - Zhixin Zhu
  - Xiaoxia Zhu
  - Yanru Chu
  - Bing Zhang
  - Yi Chen
- PubMed: 40969681
- DOI: 10.1016/j.eclinm.2025.103479
3 Insights on
- Reduced Upper Respiratory Infections
- High evidence
Bifidobacterium animalis (RR = 0.79, 95% CI: 0.63, 0.99; n = 3; moderate certainty) ... were the most effective interventions for reducing RTI incidence.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Bifidobacterium animalis subsp. lactis BLa80 for preventing allergic, respiratory, and gastrointestinal diseases in young children in China: a randomized double-blind placebo-controlled trial.
- 2026-02-15
- RCT · n = 180
- Clinical and experimental pediatrics 69(2)
- - Ke Chen
  - Xi Zhang
  - Kaihong Zeng
  - Jiayi Zhong
  - Shanshan Jin
  - Yang Nie
  - Ping Yang
  - Nianyang He
  - Haixia Chen
  - Yanmei Cao
  - Yunrong Fu
  - Ziji Fang
  - Wei Jiang
  - Changqi Lium
- PubMed: 41167178
- DOI: 10.3345/cep.2025.01256
7 Insights on
- Reduced Upper Respiratory Infections
- High evidence
Probiotic supplementation was also associated with a lower risk of URTIs (IG vs. CG: 40.3% vs. 20.7%; risk ratio [RR], 0.752; 95% confidence interval [CI], 0.653-0.866).
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Multi-Strain Probiotic and Common Infections in Early Childhood Education Settings: A Randomised Controlled Trial.
- 2026-01-23
- RCT · n = 118
- Journal of paediatrics and child health 62(3)
- - Hafiz Haris Ahmad
  - Blake Peck
  - Daniel Terry
- PubMed: 41574644
- DOI: 10.1111/jpc.70295
3 Insights on
- Reduced Upper Respiratory Infections
- High evidence
- Large Human Trial
However, probiotic supplementation had no impact on respiratory tract infections (RTIs).
Effect
Neutral
Effect size
Small
Significant
No
Use of a probiotic mixture containing Bifidobacterium animalis subsp. lactis BB-12 and Enterococcus faecium L3 as prophylaxis to reduce the incidence of acute gastroenteritis and upper respiratory tract infections in children.
- 2021-05
- RCT
- Minerva pediatrics 73(3)
- - Francesco DI Pierro
  - Patrizia Lo Russo
  - Maria L Danza
  - Isabella Basile
  - Stefania Soardo
  - Giovanni Capocasale
  - Sandro B Paparone
  - Vittoria Paletta
  - Cosimo Lanza
  - Elvira Schiavone
  - Paolo Risso
  - Maria Colombo
- PubMed: 32506882
- DOI: 10.23736/s2724-5276.20.05925-3
5 Insights on
- Reduced Upper Respiratory Infections
- High evidence
the incidence and duration of episodes of URTIs by 84% and 50%
Effect
Beneficial
Effect size
Large
Significant
Yes
The Science behind the Probiotic Strain Bifidobacterium animalis subsp. lactis BB-12®
- 2014-03-28
- Review
- Microorganisms 2(2)
- - Mikkel Jungersen
  - A. Wind
  - E. Johansen
  - J. Christensen
  - Birgitte Stuer-Lauridsen
  - D. Eskesen
- PubMed: 27682233
- DOI: 10.3390/microorganisms2020092
15 Insights on
- Reduced Upper Respiratory Infections
- High evidence
- Highly Cited
- Rigorous Journal
In terms of immune function, clinical studies have shown that BB-12(®) increases the body's resistance to common respiratory infections as well as reduces the incidence of acute respiratory tract infections.
Effect
Beneficial
Effect size
Moderate

Bifidobacterium animalis subsp. lactis BB-12 and Reduced Upper Respiratory Infections

Bifidobacterium animalis subsp. lactis BB-12 in reducing the risk of infections in early childhood

Comparative effectiveness of oral nutritional supplements in preventing respiratory tract infections among adults: a systematic review and network meta-analysis.

Bifidobacterium animalis subsp. lactis BLa80 for preventing allergic, respiratory, and gastrointestinal diseases in young children in China: a randomized double-blind placebo-controlled trial.

Multi-Strain Probiotic and Common Infections in Early Childhood Education Settings: A Randomised Controlled Trial.

Use of a probiotic mixture containing Bifidobacterium animalis subsp. lactis BB-12 and Enterococcus faecium L3 as prophylaxis to reduce the incidence of acute gastroenteritis and upper respiratory tract infections in children.

The Science behind the Probiotic Strain Bifidobacterium animalis subsp. lactis BB-12®