Benefits
Visceral fat area and body fat mass in adults with larger abdominal fat areas
In 210 adults with larger visceral fat areas on CT, 200 g a day of fermented milk with the strain for 12 weeks lowered visceral fat area, the main outcome, by about 8% versus under 1% on the same milk without it, and body fat mass fell by about 0.5 kg as it rose on the control milk. Four weeks after stopping, the fat mass change had largely faded; visceral fat was not rescanned. Maker scientists ran the trial.
Body weight, BMI and waist size during daily fermented milk intake
In the 210-person trial, BMI, waist and hip fell slightly more than on the control milk at 12 weeks, BMI by about 1 to 1.6%. In an earlier 87-person trial, body weight fell about 1.1 kg and waist about 1.7 cm within the strain group while none fell significantly on the control milk; that abstract reports within-group changes only.
Fat excretion and blood fatty acids after a fat-rich meal
In 20 adults with high fasting triglycerides, 4 weeks of strain fermented milk lowered blood free fatty acids after a high-fat test meal compared with an earlier control period, in a fixed, single-blind order. In 30 healthy adults on a set diet for 7 days, fecal fat rose on the strain, but the gap versus control milk was not significant.
Self-rated nose and throat symptom days during winter
In three 12-week winter trials of about 200 adults each, drinkable yogurt or capsules with the strain cut the share of days with several self-rated symptoms such as plugged nose and hoarseness. The tests pooled symptom-days rather than people, chill, headache, tiredness or runny nose were more frequent on the strain in some trials or subgroups, and the maker ran all three.
Antibody response after a seasonal vaccine
In 188 adults given drinkable yogurt with the strain for 16 weeks and a flu vaccine at week 4, antibody titers to two of three vaccine strains were higher than on plain yogurt at some time points, while the third strain and seroconversion rates did not differ. In later winter trials, NK activity and serum antibodies did not differ from placebo.
Survival through the human gut
In small feeding studies, a traceable variant of the strain was recovered from stool after oral intake, and in seven adults eating yogurt with the strain, fecal lactobacilli rose and most were L. gasseri by week 2. In the capsule trial, the share of Lactobacillus in stool was slightly higher than on placebo at 12 weeks.
Mechanism of action
Larger fat droplets and slower fat absorption (lab and rat work)
In the lab, the strain enlarged fat emulsion droplets and slowed fat breakdown by pancreatic lipase more than four other lactic acid bacteria. In rats, milk fermented with it lowered peak triglyceride transport in lymph and raised fecal fat. A 7-day human study did not show a significant fecal fat gain versus control.
Gut barrier and fat tissue inflammation in mice (animal work)
In mice fed a high-fat diet for 21 weeks, the strain limited weight and visceral fat gain, reduced gut leakiness and blood antibodies to bacterial wall material and shifted fat tissue immune cells toward a less inflammatory type. These maker-run results have not been measured in people.
Dendritic cell signaling through bacterial DNA (lab work)
In human blood cell cultures, DNA from the strain activated plasmacytoid dendritic cells and raised interferon-alpha through the TLR9 receptor. In the human trials, these cell markers did not differ from placebo overall and rose only in subgroups.
Clinical trials
Multicenter, double-blind, randomized parallel-group trial run by a contract research organization; 200 g a day of fermented milk made with 10^7 or 10^6 CFU of SBT2055 per gram (measured about 7.9 x 10^7 and 6.9 x 10^6) or 0 (control milk with the same yogurt cultures) for 12 weeks, then 4 weeks off; the stated primary outcome was the change in CT visceral fat area; between-group comparisons of change from baseline were Bonferroni-adjusted (the sample size was powered on within-group change), and the paper names no analysis population beyond the 210 in its baseline table; no registry number is reported; no specific grant, and six of nine authors work for Megmilk Snow Brand (Kadooka et al. 2013, Br J Nutr)
210 healthy Japanese adults aged 35 to 60 (105 men, 105 women) with visceral fat areas of 80.2 to 187.8 cm2 and a mean BMI of about 27.
At week 12, visceral fat area changed by -8.5% and -8.2% in the two strain groups versus -0.7% on control milk, significant against control for both doses. Body fat mass (about -0.6 and -0.5 kg versus +0.5 kg), BMI, waist and hip also differed from control; subcutaneous fat did not. Four weeks after stopping, the BMI, waist, hip and fat mass changes had shrunk and fat mass was no longer significantly below baseline; visceral fat was not rescanned after stopping. No product-related adverse events.
Multicenter, double-blind, randomized placebo-controlled trial; 200 g a day of fermented milk with SBT2055 or the same fermented milk without it for 12 weeks, with abdominal fat area measured by CT; the follow-up paper describes this product as 10^8 CFU per gram, while the maker's website gives 5 x 10^8 per gram; the first author was at Snow Brand Milk Products, and the abstract states no funding source (Kadooka et al. 2010, Eur J Clin Nutr)
87 Japanese adults with a BMI of 24.2 to 30.7 and visceral fat areas of 81.2 to 178.5 cm2 (43 strain, 44 control).
Within the strain group, visceral fat area fell 4.6% (about 5.8 cm2), subcutaneous fat 3.3%, body weight 1.4% (about 1.1 kg), BMI 1.5%, waist 1.8% and hip 1.5% from baseline, while none of these fell significantly in the control group. High-molecular-weight adiponectin rose in both groups. The abstract reports changes within each group, not a between-group test.
Single-blind, placebo-controlled, within-subject trial (UMIN000011605) in a fixed order: 4 weeks of control fermented milk, a 4-week washout, then 4 weeks of fermented milk with SBT2055 (about 5 x 10^10 CFU per 100 g), 200 g a day, with an 8-hour fat-loading test after each period; three of five authors list Megmilk Snow Brand affiliations (Ogawa et al. 2014, Lipids Health Dis)
20 Japanese adults (15 men, 5 women) with fasting triglycerides above 200 mg/dl.
After the strain period, blood free fatty acids from 2 to 8 hours after the test meal and triglycerides at 2 hours were lower than after the control period, and fasting free fatty acids fell more. The overall triglyceride response, body weight and BMI did not differ between periods. The order was not randomized, so period effects cannot be excluded.
Double-blind, randomized, placebo-controlled trial (UMIN000015772); 100 g a day of fermented milk with SBT2055 (about 5 x 10^9 CFU per 100 g) or without it for 7 days after a 7-day run-in, with all meals provided; fecal fat was the clinical measure; all five authors work for Megmilk Snow Brand (Ogawa et al. 2015, Lipids Health Dis)
30 healthy Japanese adults aged 27 to 69 (12 men, 18 women), 15 per group.
Fecal fat rose from the run-in period in the strain group and not in the control group, but the difference in change between groups was not significant (P = 0.086). Body weight and BMI fell similarly in both groups. No participant dropped out.
Randomized, double-blind, placebo-controlled parallel-group trial (UMIN000019264); 100 g a day of drinkable yogurt with at least 10^9 CFU of SBT2055 per 100 g or the same yogurt without it for 16 weeks, with a trivalent flu vaccine at week 4; the primary objective was the vaccine-specific antibody response; four of six authors work for Megmilk Snow Brand; not indexed in PubMed (Nishihira et al. 2016, Funct Foods Health Dis)
200 healthy Japanese adults randomized, 188 analyzed (94 per group), about 82% women, mean age about 49.
Antibody titers against the H1N1 and B vaccine strains were higher than on placebo at some time points, and seroprotection against B was higher at week 11, while titers against H3N2 and seroconversion rates did not differ. Changes in plasma IgG, salivary IgA and NK cell activity favored the strain at some time points. No safety concerns were found.
Randomized, double-blind, placebo-controlled parallel-group trial (UMIN000045901); one bottle a day of drinkable yogurt with at least 10^9 CFU of SBT2055 per 100 g or the same yogurt without it for 12 weeks; the primary outcome was a daily diary of cold-like symptoms, analyzed as pooled symptom-days by chi-square test without adjustment across ten symptoms; funded by Megmilk Snow Brand, which employs four of six authors (Kobatake et al. 2022, Front Nutr)
200 Japanese adults aged 20 to 64 who said they catch colds easily; 193 analyzed per protocol.
Nine of ten symptoms were recorded on a smaller share of days on the strain (for example plugged nose on 17.7% versus 27.7% of days), while chill was more frequent. Salivary IgA rose more at week 4 only; NK cell activity, serum IgA and IgG did not differ. Of 112 adverse events, none was judged related to the product.
Randomized, double-blind, placebo-controlled parallel-group trial (UMIN000049183); three enteric-coated capsules a day giving more than 10^9 CFU of SBT2055, or starch capsules, for 12 weeks; the primary outcome was the daily symptom diary, analyzed as pooled symptom-days by chi-square test; no external funding, and three of five authors work for Megmilk Snow Brand (Kobatake et al. 2023, Nutrients)
200 Japanese adults aged 20 to 64 who catch colds often; 191 analyzed.
Runny nose, plugged nose, sneezing, sore throat, hoarseness and chill were recorded on fewer days, but headache and tiredness on more days, and cough and fever did not differ. Dendritic cell activation markers, salivary IgA, serum antibodies and NK activity did not differ overall; CD86, a dendritic cell marker, rose in a low-salivary-IgA subgroup. No product-related adverse events.
Randomized, double-blind, placebo-controlled parallel-group trial (UMIN000055950); one 100 g bottle a day of drinkable yogurt with at least 10^9 CFU of SBT2055 or the same yogurt without it for 12 weeks; the primary outcome was the daily symptom diary (pooled symptom-days, chi-square test), with dendritic cell activity and IFN-alpha production secondary; no financial support declared, and three of five authors work for Megmilk Snow Brand (Kobatake et al. 2025, Front Nutr)
200 Japanese adults aged 20 to 64 who catch colds easily; 188 analyzed.
Nine of twelve symptoms were recorded on fewer days over 12 weeks, while runny nose, sore throat and fatigue did not differ over 12 weeks, and runny nose was more frequent on the strain in weeks 1 to 4. Dendritic cell markers and IFN-alpha production did not differ overall; markers rose in participants under 40 in a prespecified age analysis, and in those 40 and over runny nose and sore throat were more frequent on the strain. One mild case of itching was judged probably related.