Our "No Return Necessary"
Money-Back Guarantee

If you don’t like something of ours, guess what happens next?

No, we don’t request you deliver it to a PO box in the Gobi Desert by carrier pigeon. Nor do we ask you to fill a cursed inkwell with orc’s blood and demon saliva and then use it to complete reams of return forms written in ancient Cyrillic script.

We just . . . wait for it . . . give you your money back. Holy moo cows. And that means you can say "yes" now and decide later.

Will Biome “power wash” your gut and automagically eradicate acne, allergies, and asthma?

No.

Will it supercharge your metabolism and flatten your stomach in 30 days?

Absolutely not.

But will Biome improve nutrient absorption, reduce stomach pain and bloating, and decrease intestinal and whole-body inflammation?

Yes. Or your money back.

  • Total formulation transparency (no proprietary blends)[8] This means you know exactly what’s in every serving of Biome—every dose of every ingredient—and can verify the accuracy and efficacy of the formulation.
  • Made in the USA with globally sourced ingredients in NSF-certified and FDA-inspected and cGMP-compliant facilities
  • Backed by our “No Return Necessary” money-back guarantee that works like this: If you don’t absolutely love Biome, just let us know, and we’ll give you a full refund on the spot. No forms or returns necessary.

So order now, try Biome risk free, and see for yourself why we believe it’s the perfect probiotic supplement.

Will Biome “power wash” your gut and automagically eradicate acne, allergies, and asthma?

No.

Will it supercharge your metabolism and flatten your stomach in 30 days?

Absolutely not.

But is Biome the only[1] Most popular probiotics are all-natural. Some contain the right mix of high-quality bacteria strains. Some provide clinically effective doses. But only Biome checks each of these boxes. natural[2] Biome doesn’t just “contain natural ingredients''—every ingredient is naturally sourced. Biome contains no artificial or synthetic substances of any kind. probiotic supplement with clinically effective doses[3] Every serving of Biome contains 1,192 milligrams of active ingredients that have been shown to be safe and effective in peer-reviewed scientific research. of 4 ingredients scientifically shown[4] Each active ingredient in Biome is backed by published scientific studies that show benefits in healthy humans. to improve digestive health and function and promote a leaner body composition?

And will it improve nutrient absorption, reduce stomach pain and bloating, and decrease intestinal and whole-body inflammation?

Yes. Or your money back.

  • 19 peer-reviewed scientific studies support Biome's combination of ingredients and doses[5] That’s 250 pages of scientific research that shows Biome works exactly like we say it does.
  • Contains no artificial fillers, food dyes, or other chemical junk[6] While these types of chemicals may not be as dangerous as some people claim, studies suggest that regular consumption of them may indeed be harmful to our health. And that’s why you won’t find them in Biome.
  • Analyzed for purity and potency in a state-of-the-art ISO 17025 accredited lab[7] Every bottle of Biome is guaranteed to provide exactly what the label claims and nothing else—no heavy metals, microbes, allergens, or other contaminants.
  • Total formulation transparency (no proprietary blends)[8] This means you know exactly what’s in every serving of Biome—every dose of every ingredient—and can verify the accuracy and efficacy of the formulation.
  • Made in the USA with globally sourced ingredients in NSF-certified and FDA-inspected and cGMP-compliant facilities

Biome is also backed by our “No Return Necessary” money-back guarantee that works like this:

If you don’t absolutely love Biome, just let us know, and we’ll give you a full refund on the spot. No forms or returns necessary.

So order now, try Biome risk free, and see for yourself why we believe it’s the perfect probiotic supplement.

Notice to California Consumers

WARNING: Consuming this product can expose you to chemicals including lead which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov/food.

Legion Biome Ingredients (1,192 milligrams per serving)

Bifidobacterium lactis B420® (10 billion CFU per serving)

Bifidobacterium lactis B420® is a strain of probiotic bacteria that reduces the production of toxic compounds that are produced by harmful intestinal bacteria and can cause inflammation throughout the body.[9]

Bifidobacterium lactis B420® also boosts levels of healthful bacteria in the digestive tract as well as concentrations of a protein called GLP-1 that influences the release of insulin from the pancreas (and thus glucose control) and other hormones that impact appetite.[10][11]

Research shows supplementation with Bifidobacterium lactis B420® . . .

  • Decreases intestinal inflammation[12]
  • Reduces food intake and promotes fat loss (particularly in the stomach region) and weight maintenance through mechanisms not fully understood yet, but possibly related to improvements in the function of the gut barrier[13]
  • May improve the function of the gut barrier, which controls the absorption of nutrients, electrolytes, and water, as well as the containment and elimination of toxins and pathogens[14][15][16]

The clinically effective dose of Bifidobacterium lactis B420® is 10 billion CFU.

Bacillus subtilis DE111® (5 billion CFU per serving)

Bacillus subtilis DE111® is a strain of probiotic bacteria that increases the production of white blood cells in response to inflammation, positively influences hormones related to satiety (fullness), and boosts levels of healthy bacteria in the digestive tract.[17][18][19]

Research shows supplementation with Bacillus subtilis DE111® . . .

  • Increases the body’s ability to fight off infections[20]
  • Reduces whole-body inflammation levels[21]
  • Improves cholesterol levels and blood vessel function[22]
  • May promote fat loss through mechanisms not fully understood yet, but possibly related to improvements in the function of the gut barrier[23]

The clinically effective dose of Bacillus subtilis DE111® is 5 billion CFU.

Lactobacillus plantarum 299v® (10 billion CFU per serving)

Lactobacillus plantarum 299v® is a strain of probiotic bacteria that improves the function of the gut barrier, which controls the absorption of nutrients, electrolytes, and water, as well as the containment and elimination of toxins and pathogens.[24]

Lactobacillus plantarum 299v® also reduces the levels of “bad” bacteria in the digestive system and enhances the production of short-chain fatty acids, which nourish intestinal cells.[25]

Research shows supplementation with Lactobacillus plantarum 299v® . . .

  • Reduces abdominal pain, cramping, bloating, and flatulence[26][27]
  • Improves symptoms of Irritable Bowel Syndrome (IBS)[28][29]
  • Improves the body’s ability to absorb iron[30]

The clinically effective dose of Lactobacillus plantarum 299v® is 10 billion CFU.

PreticX® Xylooligosaccharide (1,000 milligrams per serving)

A prebiotic is a form of non-digestible fiber that serves as food for beneficial gut bacteria, helping them grow faster and replace the “bad” bacteria in your digestive system. A xylooligosaccharide is a form of prebiotic that’s naturally found in fruit, vegetables, milk, and honey.

We chose PreticX® xylooligosaccharide specifically because studies show that it’s effective at lower doses than most other prebiotics.[31]

Research shows supplementation with PreticX® xylooligosaccharide . . .

  • Increases levels of healthy intestinal bacteria[32]
  • Reduces the growth of gut bacteria that cause inflammation and are associated with an increased risk of type-2 diabetes[33]

The clinically effective dose of PreticX® xylooligosaccharide is 1,000 milligrams.

No Artificial Food Dyes or Other Chemical Junk

Artificial food dyes aren’t a hazard per se, but studies show they can cause negative effects in some people, including gastrointestinal toxicity and behavioral disorders.[34][35][36][37][38]

No Artificial Food Dyes or Other Chemical Junk

Third-Party Lab Tested for Potency & Purity

Every bottle of Biome is analyzed in a state-of-the-art ISO 17025 accredited lab to verify what is and isn’t in it. That way, you know exactly what you’re getting and putting into your body.

Third-Party Lab Tested for Potency & Purity
Biome Lab Test

See how Legion Biome compares to the rest.

  • Active Ingredients
  • Clinically Effective Ingredients & Doses
  • Bifidobacterium lactis
  • Bacillus subtilis
  • Lactobacillus plantarum
  • Xylooligosaccharide
  • Third-Party Lab Tested
  • Labdoor Certified Brand
  • Price Per Serving
  • Legion Biome
    Probiotic

    Biome
  • 1,192 mg
    per serving
  • True
  • 10 billion CFU
    per serving
  • 5 billion CFU
    per serving
  • 10 billion CFU
    per serving
  • 1,000 mg
    per serving
  • True
  • True
  • $
  • Transparent Labs
    Probiotic

    Post JYM Post-Workout
  • 1,000 mg
    per serving
  • False
  • 10 billion CFU
    per serving
  • False
  • 10 billion CFU
    per serving
  • False
  • True
  • True
  • $1.53
  • Garden of Life
    Probiotic

    PEScience TruCreatine+
  • 625 mg
    per serving
  • Question Mark
  • close
    (proprietary blend)

    A proprietary blend is a group of ingredients that lists their names but not amounts, making it impossible to know if the dosages are at clinically effective levels.

  • False
  • close
    (proprietary blend)

    A proprietary blend is a group of ingredients that lists their names but not amounts, making it impossible to know if the dosages are at clinically effective levels.

  • False
  • Question Mark
  • True
  • $1.43
  • NOW Foods
    Probiotic-10

    Cellucor M5 Ultimate
  • 640 mg
    per serving
  • Question Mark
  • close
    (proprietary blend)

    A proprietary blend is a group of ingredients that lists their names but not amounts, making it impossible to know if the dosages are at clinically effective levels.

  • False
  • close
    (proprietary blend)

    A proprietary blend is a group of ingredients that lists their names but not amounts, making it impossible to know if the dosages are at clinically effective levels.

  • False
  • Question Mark
  • False
  • $1.50

The #1 brand of all-natural sports supplements.

Over 5+ million bottles sold to over 1+ million customers who have left us over 45,000 5-star reviews.

Natural Ingredients
Natural Ingredients

Biome doesn’t just “contain natural ingredients”—every ingredient is naturally sourced. We don’t use artificial or synthetic substances of any kind.

Science-Backed Ingredients
Science-Backed Ingredients

Every ingredient in Biome is backed by peer-reviewed scientific research demonstrating clear benefits in healthy humans.

Clinically Effective Doses
Clinically Effective Ingredients & Doses

Every ingredient in Biome is included at clinically effective levels, which are the exact amounts shown to be safe and effective in peer-reviewed scientific research.

Lab Tested
Third-Party Lab Tested

Biome is tested by third-party labs for heavy metals, microbes, allergens, and other contaminants to ensure it meets FDA purity standards.

Made in USA
Made in the USA

Biome is made in America with globally sourced ingredients in NSF-certified, FDA-inspected facilities that adhere to Current Good Manufacturing Practice (cGMP) standards.

100% Money-Back-Guarantee
"No Return Necessary"
Money-Back Guarantee

If you don't absolutely love Biome, you get a prompt and courteous refund. No forms or returns necessary.

Trusted by scientists, doctors, and everyday fitness folk alike.

Previous
  • Sal Di Stefano, Justin Andrews, and Adam Schafer

    "When it comes to quality and integrity, Legion is among the best. Their products only include ingredients that are backed by research and in doses that are proven to be effective in scientific studies."

    Sal Di Stefano, Justin Andrews, and Adam Schafer

    Hosts of The Mind Pump Podcast
  • Dr. Bill Campbell, PhD

    "Legion is science-based at its core. Not only do they dose all of their products based on the clinical doses proven to be effective by scientific studies, they go above and beyond the their competitors by funding new research."

    Dr. Bill Campbell, PhD

    Professor of Exercise Science at University of South Florida
  • Jordan Syatt

    "Legion is a tremendous company run by people I trust and respect. The quality of their supplements is second to no one. And while I don’t use many supplements, the only ones I do come from Legion."

    Jordan Syatt

    Strength and Nutrition Coach
  • Dr. Spencer Nadolsky, MD

    "There are a lot of sleazy supplement companies out there, but Legion is not one of them. Their products are free of fillers and inactive ingredients and they take the time (and money) to test them with independent labs to ensure you're getting what you pay for."

    Dr. Spencer Nadolsky, MD

    Board-Certified Family Medicine Physician and a Diplomate of the American Board of Obesity Medicine
  • Menno Henselmans, MS

    "Legion consults with nutrition experts to make honest, science-based products and then proves they're genuine with independent lab work. That's how all supplement companies should operate."

    Menno Henselmans, MS

    Founder of Bayesian Bodybuilding, Published Scientist, and Physique Coach
  • Kurtis Frank

    "With Legion, you really do get what you pay for. Each and every product is packed with effective doses of effective ingredients, and what’s on the label is what's actually in the bottle."

    Kurtis Frank

    Co-Founder and Former Lead Researcher & Writer of Examine.com
  • James Krieger, MS

    "There are three reasons I like Legion. First, they use ingredients backed by independent, peer-reviewed scientific studies. Second, the quality of their supplements exceeds many in the industry and you know you’re getting what’s on the label. Third, Mike Matthews is a solid evidence-based guy who doesn’t over-hype."

    James Krieger, MS

    Published Scientist, Author, and Speaker
  • Chris Barakat, MS

    "Legion is the only company doing everything right. They make effective products that are backed by scientific evidence, properly dose all of their ingredients, source every ingredient from the highest-quality sources, and are transparent about exactly what goes in each and every product."

    Chris Barakat, MS

    Published Scientist and Physique Coach
Next

Frequently Asked Questions

How do I use Biome?
What makes Biome different from other probiotics on the market?
Can Biome help me if I don’t have any digestive issues?
What’s the difference between Biome and Balance?
Can I take Biome and Balance together?
How long will it take before I notice results?
Does Biome require refrigeration?
What does the Prop65 warning on the labels mean?
Can I take Biome while pregnant or breastfeeding?
Can Biome be taken with medication?
Is Biome gluten-free? Soy-free? Dairy-free?
Is Biome vegetarian friendly?
Is Biome vegan friendly?

+References

9. Science Review: Bifidobacterium lactis 420

Metagenics Institute. Accessed October 16, 2022.

10. Science Review: Bifidobacterium lactis 420

Metagenics Institute. Accessed October 16, 2022.

11. Probiotic or synbiotic alters the gut microbiota and metabolism in a randomised controlled trial of weight management in overweight adults.

Hibberd AA, Yde CC, Ziegler ML, et al. Benef Microbes. 2019;10(2):121-135. doi:10.3920/BM2018.0028.

12. Bifidobacterium animalis subsp. lactis 420 for Metabolic Health: Review of the Research.

Uusitupa HM, Rasinkangas P, Lehtinen MJ, et al. Nutrients. 2020;12(4):892. Published 2020 Mar 25. doi:10.3390/nu12040892.

13. Probiotic With or Without Fiber Controls Body Fat Mass, Associated With Serum Zonulin, in Overweight and Obese Adults-Randomized Controlled Trial.

Stenman LK, Lehtinen MJ, Meland N, et al. EBioMedicine. 2016;13:190-200. doi:10.1016/j.ebiom.2016.10.036.

14. Probiotic or synbiotic alters the gut microbiota and metabolism in a randomised controlled trial of weight management in overweight adults.

Hibberd AA, Yde CC, Ziegler ML, et al. Benef Microbes. 2019;10(2):121-135. doi:10.3920/BM2018.0028.

15. Cross-talk between Akkermansia muciniphila and intestinal epithelium controls diet-induced obesity.

Everard A, Belzer C, Geurts L, et al. Proc Natl Acad Sci U S A. 2013;110(22):9066-9071. doi:10.1073/pnas.1219451110.

16. Probiotic With or Without Fiber Controls Body Fat Mass, Associated With Serum Zonulin, in Overweight and Obese Adults-Randomized Controlled Trial.

Stenman LK, Lehtinen MJ, Meland N, et al. EBioMedicine. 2016;13:190-200. doi:10.1016/j.ebiom.2016.10.036.

17. Examining the Gastrointestinal and Immunomodulatory Effects of the Novel Probiotic Bacillus subtilis DE111.

Freedman KE, Hill JL, Wei Y, et al. Int J Mol Sci. 2021;22(5):2453. Published 2021 Feb 28. doi:10.3390/ijms22052453.

18. Effects of Probiotic (Bacillus subtilis) Supplementation During Offseason Resistance Training in Female Division I Athletes.

Toohey JC, Townsend JR, Johnson SB, et al. J Strength Cond Res. 2020;34(11):3173-3181. doi:10.1519/JSC.0000000000002675.

19. Presence and Germination of the Probiotic Bacillus subtilis DE111® in the Human Small Intestinal Tract: A Randomized, Crossover, Double-Blind, and Placebo-Controlled Study.

Colom J, Freitas D, Simon A, et al. Front Microbiol. 2021;12:715863. Published 2021 Aug 2. doi:10.3389/fmicb.2021.715863.

20. Examining the Gastrointestinal and Immunomodulatory Effects of the Novel Probiotic Bacillus subtilis DE111.

Freedman KE, Hill JL, Wei Y, et al. Int J Mol Sci. 2021;22(5):2453. Published 2021 Feb 28. doi:10.3390/ijms22052453.

21. Effects of Probiotic (Bacillus subtilis DE111) Supplementation on Immune Function, Hormonal Status, and Physical Performance in Division I Baseball Players.

Townsend JR, Bender D, Vantrease WC, et al. Sports (Basel). 2018;6(3):70. Published 2018 Jul 26. doi:10.3390/sports6030070.

22. Bacillus subtilis DE111 intake may improve blood lipids and endothelial function in healthy adults.

Trotter RE, Vazquez AR, Grubb DS, et al. Benef Microbes. 2020;11(7):621-630. doi:10.3920/BM2020.0039.

23. Effects of Probiotic (Bacillus subtilis) Supplementation During Offseason Resistance Training in Female Division I Athletes.

Toohey JC, Townsend JR, Johnson SB, et al. J Strength Cond Res. 2020;34(11):3173-3181. doi:10.1519/JSC.0000000000002675.

24. Lactiplantibacillus plantarum 299v (LP299V®): three decades of research.

Nordström EA, Teixeira C, Montelius C, Jeppsson B, Larsson N. Benef Microbes. 2021;12(5):441-465. doi:10.3920/BM2020.0191.

25. Survival of Lactobacillus plantarum DSM 9843 (299v), and effect on the short-chain fatty acid content of faeces after ingestion of a rose-hip drink with fermented oats.

Johansson ML, Nobaek S, Berggren A, et al. Int J Food Microbiol. 1998;42(1-2):29-38. doi:10.1016/S0168-1605(98)00055-5.

26. Clinical trial: Lactobacillus plantarum 299v (DSM 9843) improves symptoms of irritable bowel syndrome.

Ducrotté P, Sawant P, Jayanthi V. World J Gastroenterol. 2012;18(30):4012-4018. doi:10.3748/wjg.v18.i30.4012.

27. Effect of probiotic species on irritable bowel syndrome symptoms: A bring up to date meta-analysis.

Ortiz-Lucas M, Tobías A, Saz P, Sebastián JJ. Rev Esp Enferm Dig. 2013;105(1):19-36. doi:10.4321/s1130-01082013000100005.

28. British Dietetic Association systematic review of systematic reviews and evidence-based practice guidelines for the use of probiotics in the management of irritable bowel syndrome in adults (2016 update).

McKenzie YA, Thompson J, Gulia P, Lomer MC; (IBS Dietetic Guideline Review Group on behalf of Gastroenterology Specialist Group of the British Dietetic Association). J Hum Nutr Diet. 2016;29(5):576-592. doi:10.1111/jhn.12386.

29. Choosing an appropriate probiotic product for your patient: An evidence-based practical guide.

Sniffen JC, McFarland LV, Evans CT, Goldstein EJC. PLoS One. 2018;13(12):e0209205. Published 2018 Dec 26. doi:10.1371/journal.pone.0209205.

30. Freeze-dried Lactobacillus plantarum 299v increases iron absorption in young females—Double isotope sequential single-blind studies in menstruating women.

Hoppe M, Önning G, Hulthén L. PLoS One. 2017;12(12):e0189141. doi:10.1371/JOURNAL.PONE.0189141.

31. Xylooligosaccharide increases bifidobacteria but not lactobacilli in human gut microbiota.

Finegold SM, Li Z, Summanen PH, et al. Food Funct. 2014;5(3):436-445. doi:10.1039/c3fo60348b.

32. Xylooligosaccharide increases bifidobacteria but not lactobacilli in human gut microbiota.

Finegold SM, Li Z, Summanen PH, et al. Food Funct. 2014;5(3):436-445. doi:10.1039/c3fo60348b.

33. Xylooligosaccharide supplementation alters gut bacteria in both healthy and prediabetic adults: a pilot study.

Yang J, Summanen PH, Henning SM, et al. Front Physiol. 2015;6:216. Published 2015 Aug 7. doi:10.3389/fphys.2015.00216.

34. Toxicological significance of azo dye metabolism by human intestinal microbiota.

Feng J, Cerniglia CE, Chen H. Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, AR , USA. Front Biosci (Elite Ed). 2012 Jan 1;4:568-86.

35. Artificial food dyes and attention deficit hyperactivity disorder.

Kanarek RB. Department of Psychology, Tufts University, Medford, Massachusetts, USA. Nutr Rev. 2011 Jul;69(7):385-91.

36. Meta-analysis of attention-deficit/hyperactivity disorder or attention-deficit/hyperactivity disorder symptoms, restriction diet, and synthetic food color additives.

Nigg JT, Lewis K, Edinger T, Falk M. Oregon Health and Science University, Portland, OR, USA. J Am Acad Child Adolesc Psychiatry. 2012 Jan;51(1):86-97.e8.

37. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial.

McCann D, Barrett A, Cooper A, Crumpler D, Dalen L, Grimshaw K, Kitchin E, Lok K, Porteous L, Prince E, Sonuga-Barke E, Warner JO, Stevenson J. School of Psychology, Department of Child Health, University of Southampton, Southampton, UK. Lancet. 2007 Nov 3;370(9598):1560-7.

38. Effect of food azo dye tartrazine on learning and memory functions in mice and rats, and the possible mechanisms involved.

Gao Y, Li C, Shen J, Yin H, An X, Jin H. Scientific and Technological College of Chemistry and Biology, Yantai Univ., Yantai, PR China. J Food Sci. 2011 Aug;76(6):T125-9.