Benefits
Infant immune development, studied in allergy-prone families (strain M-16V)
In an open trial in Japan, 130 mothers took B. breve M-16V with B. longum BB536 from 1 month before delivery and their babies took it for 6 months; fewer infants developed eczema by 18 months than in 36 untreated pairs. A 15-child study in infants with eczema reported better skin scores. Neither study was placebo-controlled, and a different B. breve strain did not boost children's vaccine responses.
Gut colonization in preterm babies (hospital use only)
In a placebo-controlled trial in 159 preterm babies, M-16V raised gut B. breve levels, and an earlier trial found better weight gain. A review of M-16V trials found no significant effect on necrotizing enterocolitis, infection or death in its pooled randomized trials, and a 1,315-baby trial of strain BBG-001 also found none. Giving probiotics to preterm babies is a hospital decision.
Infant crying time, studied in babies with colic (strain CECT7263)
In an open-label randomized trial in 150 babies with colic, B. breve CECT7263 reduced daily crying time more than simethicone, an anti-gas medicine, from the first week (68.5% vs 59.5% less crying at 4 weeks). All groups improved, there was no placebo group, and parents knew which product they were giving.
Body fat in adults with a tendency to overweight (strain B-3)
In a 12-week placebo-controlled trial in Japanese adults with a tendency toward obesity, about 50 billion CFU a day of B. breve B-3 lowered fat mass compared with placebo and improved some liver and inflammation blood markers. Most authors worked for Morinaga Milk Industry, and the result has not been confirmed by other groups in the studies cited here.
Mechanism of action
Settles in the infant gut
In a placebo-controlled trial in preterm babies, daily M-16V raised the share with detectable gut B. breve from 40% to 91%, against 3% to 38% with placebo. In an earlier trial, the given strain was found in 73% of treated babies at 2 weeks versus 12% of controls.
Effects depend on the strain
Results for one B. breve strain do not carry over to others. M-16V, BBG-001, CECT7263 and B-3 were each tested for different outcomes, and a large trial of BBG-001 in preterm babies found no benefit. Reviewers of the M-16V research stress that strain-specific data are needed.
Clinical trials
Small controlled study: 8 infants with eczema and low gut bifidobacteria received B. breve M-16V for 1 month and 7 served as controls (Hattori et al. 2003, Arerugi)
15 infants with atopic dermatitis (eczema) and low fecal bifidobacteria.
In the M-16V group, gut bifidobacteria rose and skin and total allergy symptom scores improved after 1 month. Changes in gut bacteria did not correlate with the symptom changes. The study was very small, not described as randomized or placebo-controlled, and published in Japanese.
Randomized controlled trial of B. breve given from the first days of life to very low birthweight babies, plus a preliminary safety study (Kitajima et al. 1997, Arch Dis Child Fetal Neonatal Ed)
91 very low birthweight preterm babies in the randomized study and 66 in the preliminary study.
The given strain was found in the gut of 73% of treated babies at 2 weeks versus 12% of controls. Treated babies had less air drawn from the stomach and better weight gain. No side effects were seen in the preliminary study. This is hospital use only.
Open trial without placebo: mothers took B. breve M-16V plus B. longum BB536 from 1 month before delivery, then their infants took them for 6 months (Enomoto et al. 2014, Allergol Int)
130 supplemented mother-infant pairs and 36 unsupplemented control pairs in Japan.
Fewer infants in the probiotic group developed eczema during the first 18 months (odds ratio 0.231 at 10 months and 0.304 at 18 months). No adverse effects were linked to the probiotics. The study was not placebo-controlled, the control group was small, and researchers from Morinaga Milk Industry were co-authors.
Multicentre randomized placebo-controlled phase 3 trial of B. breve BBG-001 given daily from within 48 hours of birth (Costeloe et al. 2016, Lancet)
1,315 babies born at 23 to 30 weeks in 24 hospitals in southeast England.
Necrotizing enterocolitis (9% vs 10%), late-onset sepsis (11% vs 12%) and death before discharge did not differ significantly from placebo. No probiotic-related adverse events were reported. The authors concluded the results do not support routine use of this strain.
Multicentre open-label randomized trial comparing B. breve CECT7263, B. breve plus L. fermentum CECT5716, and simethicone for 28 days (Maldonado-Lobón et al. 2021, Benef Microbes)
150 infants diagnosed with colic.
Crying time fell in all groups. The B. breve group fell from the first week and by more than simethicone each week (68.5% vs 59.5% less crying at 4 weeks), with better night sleep. There was no placebo group, parents were not blinded, and most authors were from Biosearch Life, a company in Granada.