Benefits
Skin sensitivity and barrier recovery in women with reactive skin
In a two-month placebo-controlled trial in 64 women with reactive skin, the authors report that the strain taken by mouth lowered sensitivity on a capsaicin test and sped skin barrier recovery after tape stripping, the main outcomes in a registry entry posted after the trial ended. The abstract gives no between-group statistics, and a third registered arm was not reported. L'Oréal and Nestlé ran the trial.
Scalp flaking and redness in men
In 60 healthy men with moderate to severe dandruff, a daily sachet of 1x10^9 CFU for 56 days improved flaking, scalp redness and a global clinical score more than placebo, and self-assessments agreed. The abstract does not name a primary outcome or report scalp oiliness. L'Oréal and Nestlé researchers ran the study.
Nasal congestion after a nasal allergen challenge
In a crossover trial in 31 adults with grass pollen allergy, 4 weeks of fermented milk with the strain lowered self-rated congestion after a nasal pollen challenge compared with placebo, though the objective reaction threshold did not change and no primary outcome was named. A later trial against a two-strain blend found less itching but no change in congestion, its main outcome.
Nasal symptoms during grass pollen season
In 131 adults with grass pollen allergy, 5x10^9 CFU a day for 8 weeks during the pollen season did not differ from placebo on the daily nasal symptom score, the main outcome, or on quality of life, eye symptoms, medication use or allergy antibodies. All authors were Nestlé researchers.
Stool output in hospitalized infants
In 230 boys aged 4 to 24 months admitted with acute diarrhea, 1x10^10 CFU a day for 5 days had no effect in rotavirus cases. In less severe non-rotavirus cases, stool output, stool frequency and rehydration fluid needs were lower than on placebo. This was a disease population and a subgroup result, so it does not show an effect in healthy people.
Mechanism of action
Skin inflammation signals in laboratory tests
Medium from gut cells and immune cells exposed to the strain reduced substance P-induced swelling, mast cell degranulation and TNF-alpha release in human skin explants and sped barrier recovery after detergent damage. This was laboratory work in which no one took the strain, and it is offered by the developers as a possible gut-to-skin route.
Immune markers in nasal challenge trials
In the placebo crossover trial, IL-5 from blood cells and allergen-specific IgG4 were lower after the strain. In the trial against a two-strain blend, nose fluid white cells fell, while blood cell IL-5, IL-13 and IL-10 and grass pollen IgE rose slightly, as it also did after the blend. These are markers, they moved in different directions, and the pollen-season trial found no symptom benefit.
Allergic airway inflammation in mice
When pregnant and nursing mice drank water with the strain, their offspring later sensitized to birch pollen had fewer lung eosinophils, less IL-5 and less airway inflammation, while allergen antibodies did not change. Nestlé funded this study, and it is animal work that has not been tested in people.
Clinical trials
Randomized, double-blind, placebo-controlled trial of NCC 2461 (ST11) taken by mouth for two months; a matching L'Oréal registry record (NCT01368224) lists 1x10^10 CFU a day in a powder sachet against maltodextrin and a third arm combining the strain with B. longum NCC3001 that the paper does not report (Gueniche et al. 2014, Benef Microbes).
64 women with reactive skin (32 per group) in the published analysis; the registry lists 96 women aged 18 to 35.
The authors report that the probiotic decreased skin sensitivity on a capsaicin test and sped recovery of skin barrier function after tape stripping, the registry's primary outcomes; the abstract gives no between-group statistics or results for leg dryness and cheek roughness. All eight authors were from L'Oréal or the Nestlé Research Center, and the registry was posted after the trial ended.
Randomized, placebo-controlled trial of a daily sachet with 1x10^9 CFU ST11 or placebo for 56 days, with visits every two weeks and a follow-up at day 64 (Reygagne et al. 2017, Benef Microbes).
60 healthy men aged 18 to 60 with moderate to severe dandruff.
Free and adherent dandruff, scalp redness and the global clinical score improved more than with placebo from day 1 to day 57 (all P < 0.05), self-assessments agreed, and scalp microbiota shifted more than on placebo. The abstract does not name a primary outcome or give results for scalp oiliness. No adverse events were reported. Three of seven authors were from L'Oréal and two from the Nestlé Research Center.
Randomized, double-blind, placebo-controlled crossover trial; ST11-fermented milk or placebo for two 4-week periods separated by a 6 to 8 week washout, with a grass pollen nasal provocation test after each; the abstract does not give the dose; registered NCT01150253 after the trial ended (Wassenberg et al. 2011, Clin Exp Allergy).
31 adults with grass pollen allergic rhinitis.
Self-rated nasal congestion after the challenge was lower than on placebo (P < 0.05) and nasal itching trended the same way, but the objective combined nasal reaction threshold did not change. IL-5 from blood cells and allergen-specific IgG4 were lower. The abstract and registry name no primary outcome. Nestlé sponsored the trial and the Nestlé Research Center is among the listed affiliations.
Double-blind, randomized crossover trial outside the pollen season; NCC2461 powder (about 1x10^10 CFU per sachet) and a blend of L. acidophilus ATCC SD5221 and B. lactis ATCC SD5219, 4 weeks each with a 6 to 8 week washout, with a nasal provocation test before and after each period; no placebo arm; registered NCT01233154 (Perrin et al. 2014, Clin Transl Allergy).
31 adults with grass pollen allergy; 28 completed.
The primary outcome, blocked nose after the allergen challenge, did not change, nor did the nasal reaction threshold that the registry lists as its primary outcome. NCC2461 reduced self-rated itching of the nose more than the blend did; white cells in nose fluid fell after NCC2461, though that change did not differ significantly from the blend. Some blood cytokine measures and grass pollen IgE rose, the IgE after both products, and the authors described some systemic changes as somewhat unexpected. There was no placebo arm. Seven of the 13 authors listed the Nestlé Research Center, though the paper declares no competing interests.
Double-blind, randomized, placebo-controlled parallel trial of a daily 5 g powder sachet with 5x10^9 CFU NCC 2461 or maltodextrin placebo for 8 weeks during the 2012 Berlin grass pollen season (Nembrini et al. 2015, Clin Transl Allergy).
131 adults with grass pollen allergy confirmed by skin prick test and IgE.
No significant differences from placebo in the daily nasal symptom score (the main outcome), other symptom scores, quality of life or grass pollen IgE. The authors note this contrasts with two earlier allergen challenge studies. All authors were Nestlé researchers, and Nestec funded the work.
Randomized, double-blind, placebo-controlled trial at icddr,b in Dhaka; 1x10^10 CFU lyophilized ST11 or placebo daily for 5 days (Sarker et al. 2005, Pediatrics).
230 boys aged 4 to 24 months admitted with diarrhea of less than 2 days.
No effect was seen in severe rotavirus diarrhea. In children with less severe non-rotavirus diarrhea, cumulative stool output (225 vs 381 mL/kg), stool frequency and oral rehydration solution intake were lower than on placebo, and 76% versus 49% recovered within 6 days. The abstract names no single primary outcome or funder, and lists only the first author's affiliation. This is a disease population.