Tiny Health raises $33M Series B and launches TinyAI on 200,000 microbiome profiles
Tiny Health, the Austin microbiome intelligence company, said Tuesday it closed an oversubscribed $33 million Series B led by B Capital, bringing total funding to $46 million, and introduced TinyAI trained on its proprietary dataset of nearly 200,000 microbiome profiles.
A gut or vaginal microbiome test only helps if someone can turn the report into a clear next step. Tiny Health is putting another $33 million behind research and TinyAI, trained on nearly 200,000 of its own profiles, so the guidance sits on the same data as the test.
On Tuesday, 29 September 2026, Tiny Health said it closed a $33 million Series B led by B Capital, bringing total funding to $46 million. A Series B is a later private funding round, named with a letter. GlobeNewswire carried the release, datelined Austin, Texas. The open reprint of that wire stamps it September 29, 2026, 9:00 a.m. Eastern. The company letter from founder and chief executive Cheryl Sew Hoy says the page was last updated on September 29, 2026. That page does not print an hour. The wire calls the round oversubscribed, meaning more investors wanted in than the company took. The letter says the round closed. It does not use the word oversubscribed. Tiny Health calls itself a microbiome intelligence platform for gut and vaginal testing across a person’s life. A microbiome is the community of microbes living in the gut or the vagina. Those lines are the company’s.
Who put the money in, as the pages name them. B Capital led. New investors named on both pages are Black Opal Ventures, Denver Ventures, Pave Health Ventures, Alumni Ventures, Gaingels, and Pari Passu Ventures. Existing investors also participated. The wire names Spero Ventures, The Venture City, Overwater Ventures, and others. The letter prints the same existing names, with TheVentureCity as one word. Neither page says how much each investor put in.
What Tiny Health says the money is for. The wire says the capital will advance clinical research and interventional studies, expand healthcare practitioner education, and scale Powered by Tiny, its business-to-business platform. An interventional study tries a change and watches what happens, rather than only recording what people already do. Practitioner education is teaching clinicians how to use the tests. Business-to-business means the platform is sold to clinics and companies, not only as a kit a person orders at home. Those uses are on the wire. The letter does not restate that three-part list.
The company is introducing TinyAI. Both pages call it the world’s first AI trained on Tiny Health’s proprietary dataset of nearly 200,000 microbiome profiles. Proprietary means the company holds that dataset. A profile, here, is the read of one person’s sample. TinyAI is meant to turn a person’s results into personalized, science-backed guidance tied to that test. The wire says the guidance can get more precise as the dataset grows, and that this is meant to become a better patient experience and improved health outcomes. “World’s first,” “science-backed,” and “improved health outcomes” are the company’s words. The pages do not print an outside test of TinyAI, and they do not say a regulator has cleared it.
Alongside the round, Tiny Health is committing $5 million to a Microbiome Research Program. The wire says the program is there to speed microbiome research and close the gap between the science and clinical practice, and to let researchers, clinicians, and scientific partners use Tiny Health’s testing, data, and research capabilities to study intervention strategies. The letter says the same $5 million gives those partners access to the company’s testing, data, bioinformatics pipeline, and microbiome expertise. A bioinformatics pipeline is the software path that turns a raw sequencing file into a result a person can read. Kimberley Sukhum, PhD, chief science officer, said the next breakthroughs will come from bringing more researchers and institutions into the field, and that the investment is meant to generate new evidence and collaborations. That quotation is hers, in the release.
Cheryl Sew Hoy said: “We founded Tiny Health because the science is so impactful, the need is urgent, and no one else was building for the whole lifespan.” She said what started as a solution for her own family has become the infrastructure for an entire industry, and that the round propels microbiome science as a foundational layer for the next frontier of medicine. That quotation is hers, in the release. The letter adds the family story the wire leaves out. She writes that she started the company for her daughter’s eczema, and for questions she could not get a straight answer on. She writes that four years ago the company launched the first at-home gut microbiome test built for moms and babies, and that her mother hand-packed every kit out of the garage. She writes that Tiny Health is now a gut and vaginal platform for everyone, from newborns to centenarians. A centenarian is a person who has reached 100. Those sentences are hers, in the letter. The letter’s sign-off calls her a mother of three and the founder and chief executive.
What the company says it already serves. Both pages say the platform serves nearly 200,000 customers and more than 6,000 healthcare practitioners, across independent practices, hospital systems, longevity clinics, and precision medicine groups. The wire adds consumer health companies to that list. Partners named on the wire include Fullscript, Mayo Clinic’s Executive Health and Longevity Programs, Atria Institute, and Superpower. The letter names Mayo Clinic’s Executive Health and Longevity Clinic, Atria, Superpower, and Fullscript. The wire says adult testing has now passed pediatric testing in volume, and that Powered by Tiny grew 4x last year, with dozens of enterprise partners. Four times the year before is the company’s figure. The release does not say whether that multiple is revenue, customers, or another count. Nearly 200,000 customers and nearly 200,000 microbiome profiles are two figures the company prints. It does not say that every customer equals one profile.
The wire says Tiny Health was founded in 2020 and launched in 2022. It introduced a gut microbiome test for babies, built on shotgun metagenomic sequencing, along with gut and vaginal testing for moms. Shotgun metagenomic sequencing reads a wide stretch of the genetic material in a sample, instead of checking a short list of known microbes. The company calls that method the gold standard. That phrase is Tiny Health’s. The about box says the test detects microbes across more than 120,000 genomes, down to the strain level. A genome is an organism’s full set of genetic material. A strain is a finer type inside a species. The company says it owns its in-house bioinformatics pipeline. Those lines are in the release.
The research claims, as Tiny Health states them. The letter says that in 2025 the company published a randomized controlled trial in Pediatric Allergy and Immunology, and that infants in its personalized microbiome program had 83 percent lower odds of developing eczema and allergic conditions. A randomized controlled trial assigns people to the program or to a comparison group by chance. Odds are one way to state chance. The wire describes that paper more narrowly: targeted microbiome interventions reduced infants’ odds of developing eczema by 83 percent. The wire also says Tiny Health is the only gut microbiome company that has published an interventional randomized controlled trial. “Only” is the company’s word. Both pages say this is one of four published papers, that another trial is underway, and that newer work reaches into inflammatory bowel disease, menopause, GLP-1 response, and oncology. Inflammatory bowel disease is long-term inflammation of the gut. GLP-1, here, is the company’s shorthand for a class of drugs used for blood sugar and weight. Oncology is cancer medicine. The wire says the work sits on what it calls the world’s largest longitudinal microbiome dataset. Longitudinal means the same people are measured over time. These sentences are Tiny Health’s account of its papers and its dataset. The pages do not quote the journal, and they do not say a regulator has cleared the test as a treatment.
The company says it is extending the same work into longevity and healthy aging. Both pages name Gut Microbiome Age and Gut Resilience. The wire also names Gut Body Connections, tools meant to show the gut as part of a connected system and to point at microbiome factors a person can change. Nick Whitehead, senior principal at B Capital, will join Tiny Health’s board. He said the gut microbiome is one of the most significant and underexplored frontiers in human health, and that Tiny Health has built the platform best positioned to bring that science to patients, providers, and partners at scale. That quotation is his, in the release. Adam Seabrook, a partner at B Capital, said Tiny Health translates microbiome science into insights that can change how people understand and improve their health across every stage of life. That quotation is his. The about box says B Capital manages more than $12 billion. That figure is the firm’s, not the size of this round. The release does not print a valuation for Tiny Health.
In plain terms, an Austin company that sells gut and vaginal microbiome tests said on Tuesday that B Capital led an oversubscribed $33 million Series B, taking total funding to $46 million. The company is putting $5 million into a research program and introducing TinyAI, trained on nearly 200,000 of its own microbiome profiles, so a result comes with guidance from that same data. It does not print a valuation.
The picture is a portrait of Cheryl Sew Hoy, Tiny Health’s founder and chief executive, from the company’s Series B letter. She has long dark hair and a black blazer, against a light background. The Tiny Health wordmark sits in the lower left. It is the company’s portrait for the announcement.