Benefits
Waist size and body mass index over 12 weeks
In 126 adults with abdominal obesity, heat-killed BPL1 (10 billion cells a day) lowered waist size versus placebo, while live BPL1 lowered body mass index versus placebo and showed only a trend for waist. These were registered secondary measures compared across each whole group; the main outcome, visceral fat, did not differ. Average waist loss was under 2 cm, and split by sex the differences held only in women.
Visceral fat measured by MRI
Visceral fat area, the registered main outcome of the adult trial, did not change more than placebo with live or heat-killed BPL1 after 12 weeks. It fell from baseline only in the heat-killed group. A trial of heat-inactivated BPL1 in seafood sticks with inulin and omega-3 also found no visceral fat difference.
Body fat in a 12-week crossover trial in children
In 35 children and teens with Prader-Willi syndrome, a genetic condition with intense appetite, live BPL1 did not change total body fat mass versus placebo, the main outcome. Abdominal fat as a percentage fell versus placebo only in a secondary subgroup older than 4.5 years, and appetite scores and energy intake did not change.
Fasting insulin markers (markers only)
In the same children's trial, live BPL1 lowered fasting insulin and HOMA-IR, an index calculated from fasting glucose and insulin, versus placebo, while fasting glucose and HbA1c did not differ. In adults, HOMA-IR fell from baseline with heat-killed BPL1 only. No glucose tolerance test was reported, so these are markers, not a functional result.
Visceral fat with a multi-ingredient synbiotic (blend data)
In 112 adults with overweight, a synbiotic of BPL1, three L. rhamnosus strains, two prebiotic fibers and chrysanthemum extract reduced visceral fat on DXA versus placebo after 12 weeks, while waist size and BMI did not differ. BPL1 was not given alone, so the result cannot be credited to it.
Mechanism of action
Cell wall lipoteichoic acid and fat storage (lab work)
In the nematode C. elegans, BPL1 lowered total fat and triglycerides, and lipoteichoic acid taken from its cell wall reproduced this through the IGF-1 pathway. The authors propose this cell wall molecule as a postbiotic. These are worm studies, not human results.
Weight gain and appetite hormones in rats (animal work)
Zucker fatty rats given 10 billion CFU a day of BPL1 in skim milk for 12 weeks gained less weight, ate less and had lower ghrelin than rats given skim milk alone; glucose markers did not change. In dogs, live and heat-treated BPL1 did not change glucose or insulin responses.
Gut bacteria shifts (human marker)
In the adult trial, Akkermansia in stool rose more with live BPL1 than with heat-killed cells or placebo, and its rise was inversely related to weight. In the children's trial, BPL1 caused no major change in gut microbiota composition. These are associations, not proof of how BPL1 works.
Clinical trials
Randomized, double-blind, placebo-controlled, three-arm parallel trial in Reus, Spain (NCT02921217, sponsor Biopolis S.L.); one capsule a day of 10 billion CFU of live CECT 8145, the same count heat-killed at 121 °C for 30 minutes, or maltodextrin, for 12 weeks. Registered primary outcome: change in abdominal visceral fat by MRI. Funded by the Spanish CDTI agency; five authors worked for Biopolis/ADM or Lifesequencing/ADM (Pedret et al. 2019, Int J Obes (Lond))
135 participants enrolled, adults with waist circumference of at least 102 cm (men) or 88 cm (women); 126 received the products (40 placebo, 42 live, 44 heat-killed; 83 women, 43 men).
Primary outcome null: visceral fat area did not differ from placebo for either form (P = 0.148 live, P = 0.120 heat-killed; P = 0.086 for heat-killed after also adjusting for baseline waist), although it fell from baseline in the heat-killed group. In whole-group comparisons with placebo, live cells lowered BMI (P < 0.05) and heat-killed cells lowered waist circumference, waist-to-height ratio and conicity index (P < 0.05); BMI and waist were registered secondary outcomes, the two ratios were not registered; for live cells the waist change versus placebo was only a trend (P < 0.07). When men (43) and women (83) were analyzed separately, significance remained only in women. Subcutaneous fat did not change, the two forms did not differ from each other, and the published text gives no separate result for body weight, a registered secondary outcome. Diastolic blood pressure and HOMA-IR fell from baseline in the heat-killed group, and Akkermansia rose most with live cells.
Randomized, placebo-controlled crossover trial in Barcelona, Spain (NCT03548480); live BPL1 capsules (10 billion CFU a day) or maltodextrin for 12 weeks each, separated by a 12-week washout. Main outcome: adiposity by DXA. Funded by the Barcelona Magic Line fundraising program; capsules from ADM-Biopolis, which employed three authors (Amat-Bou et al. 2020, Nutrients)
39 children and adolescents with genetically confirmed Prader-Willi syndrome, a disease population (mean age 10.4); 35 completed.
Main outcome null: total fat mass did not differ from placebo (P = 0.635), and abdominal fat showed only a trend (P = 0.082). In a secondary subgroup older than 4.5 years (n = 28), abdominal fat as a percentage fell versus placebo (P = 0.017). Fasting insulin (P = 0.033) and HOMA-IR (P = 0.031) fell versus placebo, while glucose, HbA1c, lipids, blood pressure, appetite scores and energy intake did not differ. No serious adverse events occurred.
Randomized, double-blind, placebo-controlled parallel trial in Spain (NCT03630588); 50 g a day of seafood sticks with 10 billion CFU of heat-inactivated CECT 8145, 370 mg omega-3 and 1.7 g inulin, or plain sticks, for 12 weeks, plus a 4-hour single-dose test. Primary outcome: visceral fat area by MRI. Funded by the Spanish CDTI agency; two authors were employees of Angulas Aguinaga Research Center (Companys et al. 2022, Eur J Nutr)
120 adults with abdominal obesity.
Primary outcome null: visceral fat area showed no within- or between-group differences. The abstract reports lower fasting insulin and HOMA-IR, lower pulse pressure in women, and a smaller 4-hour rise in blood triglycerides after one serving (23.9 versus 49.0 mg/dL). Because three active ingredients were given together, these results cannot be credited to BPL1 alone.
Randomized, double-blind, placebo-controlled parallel trial in China with a 6-week follow-up (ChiCTR2400088457); a synbiotic of B. animalis subsp. lactis CECT 8145, three Lacticaseibacillus rhamnosus strains, inulin, fructooligosaccharides and chrysanthemum extract, or matched placebo. Primary outcome: visceral fat area by DXA. Authors included employees of the Nutrilite Health Institute and of ADM (Li et al. 2026, Clin Nutr)
112 adults with BMI 24.0 to 34.9.
Visceral fat area fell more than on placebo by week 12 (p = 0.048), with the clearest effect in the BMI 24 to 28 subgroup, where subcutaneous fat rose (p = 0.027). BMI, waist circumference and blood biochemistry did not change significantly. As a multi-ingredient product, the result cannot be credited to BPL1 alone.
Randomized, double-blind, placebo-controlled trial in Alicante, Spain (NCT02585986); a daily capsule with 1 billion CFU in total of B. lactis CECT 8145, B. longum CECT 7347 and L. casei CECT 9104, or maltodextrin, for 12 weeks. Outcomes: SCORAD skin score and days of topical steroid use. Supported by Biopolis and Korott; three authors were Biopolis employees (Navarro-López et al. 2018, JAMA Dermatol)
50 children aged 4 to 17 with moderate atopic dermatitis, a disease population.
The SCORAD score fell 19.2 points more than on placebo (P < .001), and topical steroids were used on 7.7% versus 10.8% of patient-days. Because three strains were given together, the result cannot be credited to BPL1 alone.