Pasteurized vs. Live Akkermansia: What the Human Trials Actually Show
One bacterium, two forms, three small human trials — and no straightforward answer about which form "wins". Here is the full trial record, including what each study did and did not measure.
The short version
- Pasteurized akkermansia is an inactivated form. By the ISAPP definition it is technically a postbiotic, not a probiotic [6].
- The two completed pasteurized-form human trials (2019, n=32 completed; 2026, n=90) showed metabolic-marker effects; the 2019 trial's weight endpoint did not reach significance, and the 2026 trial's effect was on weight rebound prevention after a diet phase — not weight loss [3][4].
- The one live-form trial (n=130) used the same strain as our formula and compared live cells against a postbiotic preparation from the same bacterium [5].
- The results do not line up neatly. The honest reading: effects appear concentrated in people starting with low baseline Akkermansia — a finding consistent across trials.
One bacterium, two forms — and the naming matters
Akkermansia muciniphila reaches the market in two distinctly different states. The live form is a true probiotic in the strict ISAPP sense: live microorganisms that, in adequate amounts, confer a health benefit on the host [1]. The heat-treated form is sold as pasteurized akkermansia — and because those cells are no longer alive, the scientific community classifies it as a postbiotic: "inanimate microorganisms and/or their components that confer a health benefit on the host" [6].
Neither label is a quality judgment. Both are legitimate ingredient categories. But they are different ingredients with different stability profiles, different dose units, and — critically — different regulatory filings. Marketing that quietly blends the two forms' evidence into one story is the most common exaggeration in this category. Any of the serious akkermansia probiotics on the market should state on the label which form it contains.
Why form matters more for this bacterium than most
For typical lactobacilli, live-vs-inactivated is a settled question — the probiotic category is defined around live cells, and inactivated derivatives sit in a separate lane. For Akkermansia, the question is genuinely open, for two reasons.
First, the biology: A. muciniphila is a strict anaerobe that lives in the mucus layer and is notoriously oxygen-sensitive [2]. Keeping cells fully viable through manufacturing, shelf life and stomach transit is an engineering challenge. Pasteurization sidesteps it entirely — a heat-treated cell cannot die on the shelf.
Second, the surprise: in mouse work, a purified outer-membrane protein (Amuc_1100) partly explained why the pasteurized bacterium improved metabolic markers in obese and diabetic mice — the beneficial interaction with the gut barrier survived the heat treatment [7]. That mouse finding is what justified testing the pasteurized form in humans first. An akkermansia muciniphila probiotic buyer should understand that the live form's advantage is not obvious a priori — it has to be shown.
Trial 1 — Depommier 2019: the proof-of-concept (n=32 completed)
The first human test enrolled 40 volunteers with overweight or metabolic syndrome; 32 completed. Participants took 1010 bacteria daily for three months — live, pasteurized, or placebo [3].
| Endpoint (pasteurized arm vs. placebo) | Result | Significant? |
|---|---|---|
| Insulin sensitivity (HOMA-IR, insulin-resistant subgroup) | Improved | Yes (P=0.002) |
| Body weight | ≈ −2.27 kg | No (P=0.091) |
| Fat mass | ≈ −1.37 kg | No (P=0.092) |
| Hip circumference | ≈ −2.63 cm | No (P=0.091) |
| Waist circumference | ≈ −1.56 cm | Not the primary test |
The frequently repeated claim that this trial "showed weight loss" is not accurate: the weight endpoints trended favorable but did not reach statistical significance, and the study was an exploratory proof-of-concept, not a weight-loss trial [3]. The live arm showed weaker effects than the pasteurized arm — an unexpected result that shaped the next decade of research.
Trial 2 — Mount 2026: the maintenance question (n=90)
Published in Nature Medicine in 2026, this randomized, placebo-controlled trial tested the pasteurized form in 90 adults — with a design feature that is often misreported. Participants first completed an eight-week calorie-restricted diet that produced weight loss. They were then randomized to pasteurized Akkermansia or placebo for 24 weeks of maintenance [4].
The result: during maintenance, the placebo group regained on average about 3.2 kg while the Akkermansia group regained about 1.2 kg — a statistically significant difference (P=0.012), with roughly 40% of the treated group continuing to lose rather than regain. Subgroup analysis found the effect concentrated in participants whose baseline Akkermansia abundance was low.
The weight change in this trial happened during the diet phase, not the supplement phase. What the supplement was tested for — and showed — was less regain afterward. Writing "pasteurized Akkermansia caused weight loss" reverses the design. It is also a mouse-to-human leap to generalize this to a metabolic daily probiotic taken without any dietary program; the trial tested a specific protocol in a specific population.
Trial 3 — You 2025: the live-form test with our own strain (n=130)
The largest trial to date tested the live form — and it used the same strain contained in our formula: A. muciniphila AKK PROBIO (strain CGMCC No. 20955). One hundred thirty adults were randomized to live cells, a postbiotic preparation of the same strain, or placebo [5]. The live arm outperformed the postbiotic arm on the study's metabolic endpoints. The trial was published in a journal not indexed in PubMed, so we link the record rather than a PMID — and we flag that openly rather than dressing it up.
So which form is better?
Some brands answer this question with their own product photo. Here is the honest version:
| Trial | Form | n | Main finding | Key caveat |
|---|---|---|---|---|
| Depommier 2019 [3] | Pasteurized (also live arm) | 32 completed | Insulin sensitivity improved (insulin-resistant subgroup); weight trended, not significant | Exploratory pilot; live arm weaker |
| Mount 2026 [4] | Pasteurized | 90 | Less weight regain during 24-week maintenance (1.2 vs. 3.2 kg, P=0.012) | Weight loss itself came from the diet phase; effect concentrated in low-baseline group |
| You 2025 [5] | Live (AKK PROBIO) | 130 | Live arm outperformed postbiotic arm | Journal not PubMed-indexed; endpoints differ from trials 1–2 |
The trials differ in form, dose, population, duration and endpoints. Their conclusions genuinely conflict on live-vs-pasteurized superiority — 2019 favored pasteurized, 2025 favored live. What does replicate is narrower and more useful: the effect signal is strongest in people whose baseline Akkermansia levels are low. Any brand claiming the form question is settled — in either direction — is claiming something the record does not show.
How regulators treat each form
The regulatory paper trails are separate, and worth understanding before you buy anything:
- United States. The pasteurized form of our strain is the subject of FDA New Dietary Ingredient notification 1468 (filed March 13, 2026; FDA response May 20, 2026). An NDI notification is a safety filing — not an approval, and not an evaluation of effectiveness [8].
- European Union. The EU authorized the pasteurized form of a different strain (MucT, ATCC BAA-835) as a Novel Food under Commission Implementing Regulation (EU) 2022/168, with a maximum of 3.4×10¹⁰ cells/day and the same pregnancy/lactation exclusions [9]. That authorization is strain-specific — it does not automatically extend to other strains, including ours.
What this means when you are choosing
If you are comparing labels for the best akkermansia probiotic for your own routine, the form question is one of five worth asking — and it is answerable from the label:
- Which form? Live (check the CFU statement) or pasteurized (check for TFU and "pasteurized"/"heat-treated"). Evidence does not transfer between them.
- Which strain? A strain number (like CGMCC No. 20955 or ATCC BAA-835) tells you which trials the product can legitimately cite. Species-level names tell you nothing.
- Which dose unit? TFU for total cells, CFU for live cells — both are legitimate, but the unit should match the form claimed.
- What conditions attached? Regulatory filings for this bacterium — both the FDA notification and the EU authorization — say 18+, not for pregnant or lactating women. That is a reasonable baseline for any brand's label.
One practical note: the bacterium's name is routinely misspelled in search — even the phrase "ackermansia probiotic" shows up in query data as a common variant of the correctly spelled term. If you found this page that way, you are in the right place; the organism is named after the Dutch microbiologist Antoon Akkermans.
Our own position
GLP-X +MAX uses the live form of Akkermansia muciniphila AKK PROBIO (CGMCC No. 20955) — the strain tested in the 130-participant trial — at a disclosed dose per serving. We present the pasteurized-form trials above because you deserve the whole record, including the parts that complicate the story.*
See GLP-X +MAX →Common questions
Is pasteurized Akkermansia dead?
Yes — pasteurization inactivates the cells. That is why it is classified as a postbiotic rather than a probiotic. Inactivated does not mean inert: membrane components remain intact and are the basis of the pasteurized-form trials above.
Which form did the positive human trials use?
The 2019 pilot included both live and pasteurized arms, while the 2026 weight-maintenance trial tested a pasteurized form. The largest trial to date (2025, n=130) used the live form of our strain and compared it directly against a postbiotic preparation. There is no trial that tested both forms head-to-head against placebo under identical endpoints.
Does the FDA approve Akkermansia supplements?
No. The FDA accepted a New Dietary Ingredient notification (a safety filing) for the pasteurized form of our strain. Acceptance is procedural; it is not an approval and does not evaluate effectiveness.
Can I take Akkermansia if I am pregnant?
The regulatory filings for this bacterium exclude pregnant and lactating women from their conditions of use. If you are pregnant or nursing, talk to your doctor before taking any supplement.
Why do brands disagree about live vs. pasteurized?
Because the trial record genuinely supports different readings: the earlier trials used pasteurized cells, the largest trial favored live cells, and no head-to-head trial exists. Brands tend to cite the trial that matches their own form. We have presented both above.
References
- Hill C, Guarner F, Reid G, et al. Expert consensus document: The ISAPP consensus statement on the scope and appropriate use of the term probiotic. Nat Rev Gastroenterol Hepatol. 2014;11(8):506–514. doi:10.1038/nrgastro.2014.66. PMID 24912386.
- Derrien M, Vaughan EE, Plugge CM, de Vos WM. Akkermansia muciniphila gen. nov., sp. nov., a human intestinal mucin-degrading bacterium. Int J Syst Evol Microbiol. 2004;54(Pt 5):1469–1476. doi:10.1099/ijs.0.02873-0. PMID 15388697.
- 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. doi:10.1038/s41591-019-0495-2. PMID 31263284.
- Mount J, et al. Randomized controlled trial of pasteurized Akkermansia muciniphila for weight maintenance after dietary intervention. Nat Med. 2026. PMID 42120725.
- You T, et al. Randomized controlled trial of live Akkermansia muciniphila AKK PROBIO (CGMCC No. 20955) versus postbiotic preparation, n=130. 2025. (Journal not PubMed-indexed; record held in supplier dossier.)
- Salminen S, Collado MC, Endo A, et al. ISAPP consensus statement on the definition and scope of postbiotics. Nat Rev Gastroenterol Hepatol. 2021;18(9):649–667. doi:10.1038/s41575-021-00440-6. PMID 33948025.
- Plovier H, Everard A, Druart C, et al. A purified membrane protein from Akkermansia muciniphila or the pasteurized bacterium improves metabolism in obese and diabetic mice. Nat Med. 2017;23(1):107–113. doi:10.1038/nm.4236. PMID 27892954. (Mouse study.)
- FDA (R. Philip Yeager, Director, Division of Research and Evaluation). Response to New Dietary Ingredient Notification 1468 — Akkermansia muciniphila AKK PROBIO. May 20, 2026. Letter on file.
- Commission Implementing Regulation (EU) 2022/168 of 8 February 2022 authorising the placing on the market of pasteurised Akkermansia muciniphila as a novel food. OJ L 28, 9.2.2022, p. 5–9. See also EFSA J. 2021;19(9):e06780.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
This article is educational and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease, and it is not a substitute for consultation with a qualified healthcare professional. Where a study was conducted in animals, the species is stated in the text.
The FDA response letter was referenced in the supplied ingredient manufacturer's dossier but is not reproduced on this page. Trial 3 (You 2025) is cited with its indexing limitation stated in the text.