Short answer: Yes, there is a probiotic for visceral fat that has been tested in people. In a 12-week randomised, double-blind, placebo-controlled trial at Seoul National University Hospital, adults taking 10 billion CFU of Lactobacillus gasseri BNR17® a day finished with 21.6 cm² less visceral fat than placebo, measured by CT scan. The result belongs to the BNR17® strain, not to every product that says Lactobacillus gasseri on the label. Individual results may vary.
Same name on the label. Very different evidence inside.
You have seen them: rows of probiotics, side by side on a pharmacy shelf. Most list “Lactobacillus” on the label. Prices run from very expensive to very affordable, and online you will find cheaper ones still, making similar claims. Among all of them, very few contain a strain that has been tested in a randomised, placebo-controlled human trial for its effect on visceral fat, and nothing on the label tells you which.
That is not a labelling oversight. It is the central complication in probiotic research: strains within the same species can behave nothing alike, and most of what gets marketed as “a probiotic for gut health” or “a probiotic for weight” has never been tested for that specific outcome at all.
Lactobacillus gasseri BNR17® has. This article sets out what the strain was measured doing in human trials, at what dose, and in whom.
A strain, not a species
Lactobacillus gasseri is a species found naturally in the human gut and in breast milk. Dozens of separately isolated strains carry the name, and research on one does not transfer to another.
BNR17® is one specific strain. It was isolated from human breast milk in 2006, is patented in 10 countries, and is developed by AceBiome in Seoul. In 2017 it became the first probiotic in South Korea individually recognised by the Ministry of Food and Drug Safety (MFDS) for reducing visceral fat.
Recognition tells you a regulator reviewed the evidence. The trials tell you what that evidence is.
What the 12-week visceral fat trial measured
In 2018, a team at Seoul National University Hospital published a randomised, double-blind, placebo-controlled trial in the Journal of Medicinal Food.
- Who: 90 adults aged 20 to 75, with a body mass index between 25 and 35.
- What they took: placebo, 1 billion CFU of BNR17® a day, or 10 billion CFU a day, for 12 weeks.
- What else: every group followed the same mild diet and activity plan, so the only difference was the probiotic.
- How fat was measured: by CT scan, not by a bathroom scale or a tape measure alone.
The result: the 10 billion CFU group finished with 21.6 cm² less visceral fat than placebo (P = .012). Waist circumference also fell from baseline in both BNR17® groups. No adverse events were reported.
The lower dose did not reach significance on visceral fat. The effect showed at 10 billion CFU a day, which is the dose in one BNRThin Slim+ sachet.
Body weight did not differ significantly from placebo. The change was in where fat sits, which is the part a scale cannot see. Inches, not hype.
Not one trial. Four.
BNR17® has been studied in four human clinical trials.
- Jung et al., 2013 (n = 57, 12 weeks). From baseline in the BNR17® group: waist −2.0 cm, hip −2.8 cm, BMI −0.5.
- Kim et al., 2018 (n = 90, 12 weeks). The visceral fat trial described above.
- Shin et al., 2018. Gut comfort in adults with diarrhoea-type irritable bowel symptoms. This was not a body-fat study.
- Kim JY et al., 2018. BNR17® was found in the stool of 26 of 30 people who took it, and none of 12 on placebo. In plain terms: it arrives alive. Live to gut.
Why strain specificity matters
Does any of this apply to Lactobacillus gasseri in general? No, only to this strain, and that is true across the category.
Lactobacillus gasseri SBT2055, a different strain studied mainly in Japan and reported in a 2010 trial in the European Journal of Clinical Nutrition, has its own separate evidence for abdominal fat. The two share a species name. Their trials, doses and results are their own.
So the useful question at the pharmacy shelf is not “does it contain Lactobacillus gasseri?” It is “which strain, at what dose, and where is the trial?”
How it may work
In laboratory studies in mice, BNR17® did two things: it raised the activity of genes that burn fatty acids, and it turned dietary sugars into indigestible, fibre-like chains that left the body instead of being absorbed.
These are laboratory findings. They offer a mechanism that fits the human results; they have not yet been confirmed directly in people.
Questions people ask
Is there a probiotic for visceral fat?
Lactobacillus gasseri BNR17® is the first probiotic in South Korea recognised by the MFDS for reducing visceral fat. In its 12-week human trial, the 10 billion CFU group had 21.6 cm² less visceral fat than placebo, measured by CT scan.
Is every Lactobacillus gasseri probiotic a belly fat probiotic?
No. Evidence is strain-specific. The trials described here used the BNR17® strain at 10 billion CFU a day. A product with a different L. gasseri strain, or a lower dose, cannot borrow these results.
Did people in the trial lose weight?
Body weight did not differ significantly from placebo. The measured differences were in visceral fat (against placebo) and in waist, hip and BMI (from baseline). That is why BNR17® is described as a fat composition probiotic.
How long does it take?
The trials ran for 12 weeks. Two weeks to begin. Twelve weeks to see what the science saw.
Where can I buy BNR17® in Malaysia?
BNRThin Slim+ carries BNR17® at the trial dose: 10 billion CFU in one 2 g green-apple sachet a day, tipped straight onto the tongue. It is sold at bnr17.my, the sole authorised AceBiome distributor in Malaysia, and through selected pharmacies and clinics. Pricing and how to spot authentic stock are in the Malaysia buyer’s guide.
Where this leaves you
The label on a probiotic still will not tell you which Lactobacillus has trial data behind it. For BNR17®, the record is specific: four human trials, a CT-measured difference in visceral fat at 10 billion CFU a day, and a named strain you can look up.
Fifteen seconds a day, melted on the tongue. Individual results may vary.
BNRThin Slim+: full product details →
Related reading: L. gasseri BNR17® and Visceral Fat: What the Trials Found · Probiotic for Belly Fat? · How to Reduce Visceral Fat · TOFI explained · Fat Loss Probiotic: What the Evidence Supports · Belly Fat After 40 · The science behind BNR17®
References
- Kim J, Yun JM, Kim MK, Kwon O, Cho B. Lactobacillus gasseri BNR17 Supplementation Reduces the Visceral Fat Accumulation and Waist Circumference in Obese Adults: A Randomized, Double-Blind, Placebo-Controlled Trial. J Med Food. 2018; 21(5): 454–461.
- Jung SP, et al. Effect of Lactobacillus gasseri BNR17 on Overweight and Obese Adults: A Randomized, Double-Blind Clinical Trial. Korean J Fam Med. 2013; 34: 80–89.
- Shin et al. J Clin Biochem Nutr. 2018; 62(2): 179–186.
- Kim JY, et al. Food Sci Biotechnol. 2018; 27(3): 853–857.
- Kang et al. PLoS One. 2013; 8(1): e54617.
- Jo et al. J Microbiol. 2024; 62: 907–918.
- Kadooka Y, et al. Regulation of Abdominal Adiposity by Probiotics (Lactobacillus gasseri SBT2055) in Adults with Obese Tendencies in a Randomized Controlled Trial. Eur J Clin Nutr. 2010.