How Do Live B420 and Pasteurized Akkermansia Compare?

Live B420 vs. Pasteurized Akkermansia: How to Compare the Evidence

Live B420 and pasteurized Akkermansia can't be ranked by the number on the label. B420 is a living bifidobacterium counted in colony-forming units (CFU). Pasteurized Akkermansia is heat-killed and counted as total cells. Their key trials studied different people, doses, and questions, so compare each product with its own trial.

What Is the Difference Between Live B420 and Pasteurized Akkermansia?

Bifidobacterium animalis subsp. lactis B420 is a probiotic strain sold as live bacteria. Its main weight trial gave 10 billion CFU a day, and the count was checked during the study to confirm the bacteria stayed viable.¹

Akkermansia muciniphila is a gut bacterium that lives in the mucus layer of the intestine. In the pasteurized form, the cells are heat-treated after growth. In the first human trial, that meant 70°C for 30 minutes.³ When the European Food Safety Authority (EFSA) assessed the ingredient, it set a condition that viable cells stay below 10 CFU per gram, the limit of detection.⁷

So one ingredient is meant to arrive alive, and the other is meant not to. Brands often call heat-killed bacteria a postbiotic. The scientific definition, "a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host," also requires evidence of a benefit, so the label alone doesn't settle that question.¹⁸

Why Can't You Compare CFU With Cell Counts?

A CFU count comes from spreading a sample on a growth plate and counting the colonies that form. Only cells that can still grow show up. A total cell count, often reported as TFU (total fluorescent units), comes from flow cytometry, which counts stained cells whether or not they can grow.

EFSA's review of pasteurized Akkermansia shows how far apart these numbers can be. Batch tests listed roughly 93 billion to 223 billion cells per gram by flow cytometry, while plate counts on the same batches found under 10 to 400 CFU per gram.⁷ Same powder, two methods, results that differ by a factor of hundreds of millions.

Brands add a third label, AFU, usually spelled out as active fluorescent units. Pendulum uses AFU for its live Akkermansia, and FOLONA uses AFU for a pasteurized one.¹¹,¹³ The product pages don't describe how their counts were run, and there is no fixed conversion between flow-cytometry counts and plate counts.

In practice:

• 10 billion CFU of B420 and 10 billion cells of Akkermansia are not "the same dose." They are different organisms counted with different methods.
• A larger number doesn't mean a stronger product. A billion counted cells of one species tells you nothing about a billion colonies of another.
• Compare a label with the trial behind that same ingredient, using the same unit the trial used.

What Did the B420 Weight Trial Measure?

The main human trial for B420 is Stenman 2016, a six-month, double-blind study run at clinical centers in Finland.¹ It enrolled adults aged 18 to 65 with a BMI of 28 to 34.9 who were otherwise metabolically healthy. People with diabetes or cardiovascular disease were excluded. About 80% of participants were women, and everyone kept their usual diet and activity.

Participants mixed one sachet a day into a fruit smoothie. The four groups were placebo, polydextrose fiber (12 g), B420 alone (10 billion CFU), or B420 plus polydextrose. The prespecified primary outcome was the relative change in body fat mass measured by DXA scan.¹

Of 225 people randomized, 209 formed the intention-to-treat population, 199 entered the main body fat analysis, and 134 made up the per-protocol group of participants who followed the protocol.¹

• Main analysis: no significant difference in body fat across the four groups (P=0.46).
• Per-protocol group: B420 plus fiber showed a 4.5% lower body fat mass than placebo in an exploratory comparison. B420 alone showed −3.0%, which was not significant.
• Waist: in the per-protocol group, a post-hoc factorial analysis that pooled both B420 groups found waist circumference about 2.4 cm smaller than in the groups without B420 (P=0.004).
• Body weight: fat changes were not fully reflected in body weight. Body weight was only a trend in the B420-alone group.

Because the registered plan allowed group-by-group tests only after a significant overall test, the per-protocol and post-hoc findings stay exploratory.² DuPont Nutrition & Health, which owned B420 at the time, fully funded the study, and five authors were DuPont employees.¹

What Did the Pasteurized Akkermansia Trials Measure?

Depommier 2019: a small pilot trial

The first human trial of Akkermansia was a three-month pilot published in Nature Medicine in 2019.³ The paper reports 40 adults with overweight or obesity who also had insulin resistance and metabolic syndrome, randomized to three arms. Thirty-two completed it: 11 on placebo, 12 on pasteurized Akkermansia, and 9 on live Akkermansia. The registry record lists 54 people across four arms, including a lower-dose live arm, so the paper covers the three-month, three-arm cohort.⁴

Each active group took 10 billion cells a day, frozen in a glycerol solution and taken on an empty stomach each morning. Participants were asked to keep their normal diet and activity. The authors called it a proof-of-concept exploratory study, and they listed safety, tolerability, and metabolic markers as primary endpoints.³,⁴ The main conclusion was that both forms were safe and well tolerated.

The pasteurized group had better insulin sensitivity than placebo (+28.6%, P=0.002). That group also started with significantly worse insulin sensitivity than the placebo group, which leaves more room to improve.³ On weight and waist, nothing reached significance:

• Body weight: −2.27 kg versus placebo (P=0.091).
• Fat mass, by bioimpedance: −1.37 kg (P=0.092).
• Hip circumference: −2.63 cm (P=0.091).
• Waist circumference: about −1.56 cm, not significant.

The paper is inconsistent on the fat mass and hip results. The abstract describes them as changes from baseline, while the results section describes them as differences from placebo.³

Research grants and a prize funded the trial, including the Funds Baillet Latour, the Walloon Region, the European Research Council, and a Banque Transatlantique Belgium prize. Five authors were inventors on patent applications covering A. muciniphila in obesity, and two were co-founders of A-Mansia Biotech.³

Two newer company-sponsored trials

Two larger trials of pasteurized A. muciniphila MucT came out in 2026, and they asked different questions.

• **Weight-loss maintenance (Mount 2026, Nature Medicine):** 90 adults with overweight or obesity first followed an 8-week low-energy diet aimed at losing at least 8% of body weight. They then took pasteurized MucT or placebo for 24 weeks of unrestricted healthy eating. The primary outcome was weight change during maintenance. People on MucT regained 1.2 kg, compared with 3.2 kg on placebo (P=0.012).⁵ The Akkermansia Company sponsored the study. Its co-founder and chief technology officer, its chief medical officer, and an employee were authors, and the senior author was a scientific advisor to the company. Four authors are inventors on a patent application related to the study.⁵
• **Insulin sensitivity (Suenaert 2026, Gut Microbes):** 142 adults with metabolic syndrome took capsules with 30 billion cells of pasteurized MucT or placebo for four months. The primary endpoint, whole-body insulin sensitivity, did not differ from placebo in the intention-to-treat analysis. Lower trunk fat appeared only in an exploratory subgroup with low starting Akkermansia levels, and the weight difference in that subgroup did not reach significance (P=0.06).⁶ Two authors were company employees and three were consultants, and two co-founders of The Akkermansia Company among the authors are inventors on A. muciniphila patents.

Of the three Akkermansia trials here, the maintenance trial is the only one with a positive primary weight result, and it applies to people keeping weight off after a diet. The insulin sensitivity trial missed its primary endpoint.

How Do the Weight and Waist Results Line Up?

Sources: Stenman 2016, Depommier 2019, Mount 2026.¹,³,⁵

B420 was tested for its effect on body fat over six months in people eating as usual. Depommier tested safety and metabolic markers in a much more insulin-resistant group. Mount tested regain after a structured diet. None of these trials compared B420 with Akkermansia directly.

What Have EFSA and FDA Said About Pasteurized Akkermansia?

In 2021, EFSA concluded that pasteurized A. muciniphila is safe as a novel food at up to 34 billion cells a day for adults, excluding pregnant and breastfeeding women.⁷ The assessed strain was MucT (ATCC BAA-835), and EFSA treated the Depommier pasteurized group as having taken that ingredient. EFSA was explicit that its opinion "is not an assessment of the efficacy of the NF with regard to any (claimed) benefit."⁷ A 2025 opinion added adolescents, at up to 21 billion cells a day for ages 12 to 13 and 30 billion for ages 14 to 17. It also found that safety in pregnancy and breastfeeding has not been established.⁸

In the US, FDA's GRAS Notice Inventory concerns notices for particular ingredients and intended food uses.⁹ A GRAS notice is not approval of a dietary supplement or proof that a different strain has the same safety profile. Supplement ingredients can have other regulatory pathways, including a new dietary ingredient notification where required. FDA does not approve dietary supplements before marketing.¹⁰

How Well Do Akkermansia Products Match the Studied Formulas?

Akkermansia products sold in the US come in two forms: live or pasteurized. Depommier tested both forms, and the two 2026 trials tested pasteurized MucT. Here is how three widely sold products line up, using the formulations described on their brand and retailer pages.

Pendulum Akkermansia (live). Each capsule lists 100 million AFU of A. muciniphila WB-STR-0001 plus 276 mg chicory inulin, and the serving is one capsule.¹¹ It costs $64.99 at Vitacost, and pendulumlife.com sells it by membership at $54 a month.¹¹,¹² None of the trials above tested WB-STR-0001: the 2019 pilot's live arm was prepared by the study team, and the 2026 trials used pasteurized MucT.

FOLONA Akkermansia with Berberine (pasteurized). Each capsule lists 3 billion AFU of A. muciniphila strain AH39, 165 mg berberine HCl, and 160 mg oat beta-glucan, and FOLONA states the Akkermansia is "pasteurized rather than live." It is $30.99 on folona.com.¹³

Toniiq GLP-Core 2000 (pasteurized). A four-capsule serving lists 50 mg (5 billion TFU) of pasteurized A. muciniphila AH39 with 200 mg dihydroberberine, 1,000 mg inulin, cinnamon, gymnema, quercetin, and chromium. It is $34.97 at Vitacost for 30 servings.¹⁴

Three things decide how far the trials apply:

1. Strain. The human trials used MucT. FOLONA and Toniiq list AH39. The AH39 study cited here is a laboratory and mouse study, not a human trial. It cannot establish that AH39 reproduces the human findings for MucT.¹⁵
2. Amount and unit. The trials used 10 billion and 30 billion cells a day. The products list 3 to 5 billion in AFU or TFU, and those numbers can't be lined up with the trial counts unless the methods match.
3. Formula. The trials tested Akkermansia alone. The combination products add berberine or dihydroberberine and fibers, so their effects can't be traced to the Akkermansia alone.

How WonderBiotics Probiotics for Weight Management Matches the B420 Trial

We built WonderBiotics Probiotics for Weight Management around B420 because its trial uses the same unit as our label. Our Lab of Biotics page lists B420 at 10 billion CFU a day, the amount given in Stenman 2016, with HN019 at 2 billion CFU and dihydroberberine at 100 mg per serving.¹⁶ CFU on our label is CFU in the trial, so you can compare them directly.

The formula has 8 named strains for 20 billion CFU at expiration, plus dihydroberberine and a lemon fruit extract standardized to 70% eriocitrin, in one capsule a day.¹⁶,¹⁷ The trial gave B420 as a powder in a smoothie, with or without polydextrose. Our capsule pairs it with other strains and ingredients, so B420's trial supports the B420 dose, and no trial has tested the finished capsule as a whole.¹,¹⁶ It fits adults with overweight who want support for body fat and waist size alongside their usual eating and activity, the setting B420 was tested in.

Take one capsule a day, ideally within 30 minutes after a meal. WonderBiotics Probiotics for Weight Management is $55.40 as a one-time purchase or $47.09 a month on subscription.¹⁷

It is a supplement to support your eating, movement, and sleep plan, not a treatment for obesity or diabetes. Because the formula includes dihydroberberine, a modified form of berberine, talk with your doctor first if you take a GLP-1 medication, insulin, or another diabetes medicine. Don't stop or change a prescribed medication on your own.

A Quick Checklist for Comparing Any Two Weight Probiotics

Before you weigh one label against another, check five things:

1. Live or heat-killed? Look for "pasteurized," "heat-treated," or "thermally stabilized."
2. Which unit? CFU, AFU, and TFU don't convert into one another.
3. Which strain code? Match it to the strain named in the trial.
4. Which people and which outcome? Weight maintenance after a diet, insulin sensitivity, and body fat change in people eating as usual are separate questions.
5. Who paid for the trial? Industry funding is common, and the disclosure tells you how to weigh the results.

As a precaution, do not use our dihydroberberine-containing Weight Management formula during pregnancy or breastfeeding; safety in these groups has not been established.¹⁹

References

1. Stenman LK, Lehtinen MJ, Meland N, et al. Probiotic with or without fiber controls body fat mass, associated with serum zonulin, in overweight and obese adults: randomized controlled trial. EBioMedicine. 2016;13:190-200. PMID 27810310.
2. ClinicalTrials.gov. NCT01978691: The Effect of Separate or Combined Supplementation of Probiotic (Bifidobacterium Lactis B420) and Polydextrose on Body Fat Mass.
3. Depommier C, Everard A, Druart C, et al. Supplementation with Akkermansia muciniphila in overweight and obese human volunteers: a proof-of-concept exploratory study. Nat Med. 2019;25(7):1096-1103. PMID 31263284.
4. ClinicalTrials.gov. NCT02637115: Evaluation of the Effects Associated With the Administration of Akkermansia Muciniphila on Parameters of Metabolic Syndrome Related to Obesity.
5. Mount S, Canfora EE, Jocken JW, et al. Pasteurized Akkermansia muciniphila MucT for weight loss maintenance in people with overweight and obesity: a controlled randomized trial. Nat Med. 2026;32(6):2107-2116. PMID 42120725.
6. Suenaert P, Segers A, Rymenans L, et al. Effect of pasteurized Akkermansia muciniphila MucT on insulin sensitivity, body composition, and GLP-1 production in subjects with metabolic syndrome: impact of low baseline gut Akkermansia levels. Gut Microbes. 2026;18(1):2690689. PMID 42343233.
7. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA). Safety of pasteurised Akkermansia muciniphila as a novel food pursuant to Regulation (EU) 2015/2283. EFSA J. 2021;19(9):e06780. PMID 34484452.
8. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA). Safety of an extension of use of pasteurised Akkermansia muciniphila as a novel food pursuant to Regulation (EU) 2015/2283. EFSA J. 2025;23(9):e9632. PMID 41018002.
9. US Food and Drug Administration. GRAS Notice Inventory (ingredient-specific notices and intended food uses).
10. US Food and Drug Administration. Questions and Answers on Dietary Supplements.
11. Vitacost. Pendulum Akkermansia, 30 Capsules (product page and Supplement Facts).
12. Pendulum. Akkermansia, product page.
13. FOLONA. Akkermansia with Berberine and Oat Beta-Glucan, product page.
14. Vitacost. Toniiq GLP-Core 2000, 120 Capsules (product page and Supplement Facts).
15. Feng S, Wang S, Qu D, et al. Species- or genus-dependent immunostimulatory effects of gut-derived potential probiotics. J Genet Genomics. 2023;50(10):786-794. PMID 36356718.
16. WonderBiotics. Lab of Biotics.
17. WonderBiotics. Probiotics for Weight Management, product page.
18. Salminen S, Collado MC, Endo A, et al. The International Scientific Association of Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of postbiotics. Nat Rev Gastroenterol Hepatol. 2021;18(9):649-667. PMID 33948025.
19. Memorial Sloan Kettering Cancer Center. Berberine: pregnancy, breastfeeding, and medication precautions. These berberine precautions do not establish identical clinical risks for dihydroberberine.