Benefits
Digestive comfort and abdominal pain severity
In a trial in 330 adults with IBS, 10 billion CFU a day for 6 weeks lowered abdominal pain scores on a 0 to 10 scale by 1.6 points, versus 0.9 on placebo, and 28% versus 16% had at least a 30% drop. Pain did not differ from placebo at 3 weeks. The maker funded the trial.
Overall digestive symptom scores
In the same trial, the total symptom severity score fell 105 points on UABla-12 versus 56 on placebo, with gains in pain, bloating, bowel habit and daily life domains. A separate quality of life questionnaire did not differ from placebo. A later network analysis of IBS probiotic trials, whose only UABla-12 data came from this trial, rated it better than placebo on the total score but not on pain or bloating scores.
Stool form and consistency
In the 330 person trial, 75.5% on UABla-12 had normal stool form at 6 weeks versus 62.4% on placebo, while stool frequency did not differ. In adults with constipation, a four-strain blend with UABla-12 did not beat placebo on its symptom questionnaire, though stools normalized sooner.
Perceived stress, sleep and immune markers
In the IBS trial, perceived stress was lower than on placebo at 3 weeks but not at 6 weeks. In 87 night shift workers, 14 days of UABla-12 or DDS-1 before two night shifts gave no between-group difference in cortisol, inflammatory or immune markers, and a 22% improvement in sleep quality scores on UABla-12 was only a trend.
Respiratory recovery in children aged 3 to 12 (two-strain blend)
Children aged 3 to 12 took UABla-12 with L. acidophilus DDS-1 and a prebiotic (5 billion CFU a day) or placebo for 2 weeks after a family member fell ill. Infection rates did not differ (57% versus 65%), but infections that did occur cleared in a median 5 rather than 7 days. UABla-12's own share cannot be separated.
Skin comfort in young children (two-strain blend)
In 90 children aged 1 to 3 with moderate-to-severe atopic dermatitis, UABla-12 with L. acidophilus DDS-1 and a prebiotic, 5 billion CFU twice daily for 8 weeks, lowered the skin severity score by 34% versus 19% on placebo, with less steroid cream used. The result belongs to the blend, not UABla-12 alone.
Mechanism of action
Reaching the gut during intake
In night shift workers, fecal B. lactis rose a median 1,700-fold after 14 days of UABla-12, versus 1.3-fold on placebo, with wide variation between people. The test detected the subspecies rather than the strain itself. In a four-strain blend trial, all four strains, UABla-12 included, were more abundant in stool after intake.
Proposed gut and immune pathways
The trial authors linked the results to effects on the gut microbiota, the gut barrier and gut immune signaling, but the 330 person trial measured no microbiota or biomarkers, and the night shift trial found no between-group difference in blood immune markers. How UABla-12 might act in people is untested.
Telling the strain apart
UABla-12 is deposited as DSM 34438 and is one of several commercial strains of B. animalis subsp. lactis, alongside BB-12, a different strain from the same company. Probiotic effects are strain specific, so the strain name on the label is the practical way to know which one a product contains.
Clinical trials
Randomized, double-blind, placebo-controlled, three-arm, multicenter trial at 12 clinics in Mumbai (NCT03482765, registered before enrollment with abdominal pain change at day 42 as the primary outcome); DDS-1 at not less than 10 billion CFU, B. lactis UABla-12 at the same dose, or microcrystalline cellulose placebo, once daily for 6 weeks after a 2 week placebo run-in that excluded placebo responders; there was no combined arm; funded by UAS Laboratories, with two of three authors (Martoni, Leyer) employed by UAS Laboratories, who designed the study and wrote the manuscript, while the third author, at Vedic Lifesciences (the registry's listed sponsor), directed the study, data analysis and reporting (Martoni et al. 2020, Nutrients)
330 adults aged 18 to 70 with IBS by Rome IV criteria and average pain of at least 4 of 10 (111 DDS-1, 110 UABla-12, 109 placebo); 318 completed, 105 of them on UABla-12. The UABla-12 group was older on average (41.6 versus 37.6 years).
Abdominal pain severity, the primary outcome, fell by 1.56 points on UABla-12 versus 0.85 on placebo at day 42 (p = 0.001), but not at day 21 (p = 0.178), and 28.2% versus 15.6% were responders with a drop above 30% (p = 0.031). IBS symptom severity fell 104.5 versus 55.7 points (p < 0.001), and the day 42 stool form distribution differed from placebo (p = 0.022), with 75.5% versus 62.4% normal; stool frequency and IBS quality of life did not differ from placebo. DDS-1 did better than UABla-12 on pain (p < 0.001). Tolerability did not differ. The pairwise comparisons with placebo were not described as adjusted for multiple testing; the primary result (p = 0.001) would pass a Bonferroni cutoff of 0.025 for two active arms, the responder result would not.
Randomized, double-blind, three-arm parallel trial (ACTRN12617001552370, whose registered primary outcome was a composite immune score at day 15 that the paper does not report); DDS-1 at 10 billion CFU, B. lactis UABla-12 at 10 billion CFU, or placebo daily for 14 days before two night shifts, continued through the shifts and for 12 more days; funded by UAS Laboratories, which had input into the design and manuscript, and two authors (Martoni, Leyer) were its employees (West et al. 2020, Front Immunol)
94 adults working routine night shifts recruited and 87 analyzed (29 per group), mean age 41, 74% women.
No between-group differences were found in cortisol, acute phase proteins, adhesion markers or cytokines over the night shifts. Before the shifts, placebo showed larger within-group rises in cortisol, pentraxin and IL-1ra than the probiotic groups. Fecal B. lactis rose a median 1,700-fold in the UABla-12 group. Sleep quality scores showed a time by group effect, with a 22% fall in PSQI score (lower means better sleep) on UABla-12 that was only a trend (p = 0.06); baseline sleep scores differed between groups and were worst in the UABla-12 group. Both strains were well tolerated.