Startup Tiny Health raised $33 million in a Series B funding round led by B Capital, bringing its total funding to $46 million. The company plans to direct the capital toward expanding its work with healthcare providers and companies, developing research into the relationship between the gut microbiome and health outcomes, and expanding its team.
Existing investors, including Spero Ventures, The Venture City, and Overwater Ventures, participated in the round, along with new investors such as Black Opal Ventures and Alumni Ventures. Nick Whitehead of B Capital will also join the company’s board of directors. Tiny Health did not disclose its revenue or valuation, but said its valuation had increased substantially compared with its Series A round.
From Infant Testing to a Broader Market
Cheryl Sew Hoy founded the company in Austin in 2020, after a family experience led her to study research on the gut microbiome in children. After two years of developing the platform, Tiny Health launched an at-home infant gut microbiome test in 2022, then expanded its offerings to include pregnancy, vaginal microbiome, and adult tests. According to the company, adults now represent its largest testing segment.
Customers collect a small stool sample using a swab and send it to the company. They then receive a report explaining the microorganisms detected and what they may do, along with suggestions for next steps and links to supporting research. Tiny Health uses shotgun metagenomic sequencing to analyze microbial DNA, which, according to the company, enables it to detect a broader range of organisms than tests that look for a limited group of them.
What Is Changing in Practice?
Tiny Health no longer relies solely on direct-to-consumer sales. Through its Powered by Tiny arm, the company provides tests to healthcare providers and companies that integrate them into their services. Its partners include Superpower, Fullscript, and Mayo Clinic’s Executive Health and Longevity programs. It also serves more than 6,000 healthcare practitioners and provides training on using the reports in patient care. The company said its total revenue doubled year over year, while its business serving companies grew fourfold last year.
The company is also collecting data to develop a tool called TinyAI, which will use nearly 200,000 microbiome samples and research findings reviewed by its scientific team to help users understand their results. Tiny Health says the health data provided by customers is used after details that identify them have been removed.
Limitations and Open Questions
Cheryl Sew Hoy emphasizes that the company’s products are wellness tests, not diagnostic tools, and are not covered by insurance. The test can identify the microbes present in a sample, but it does not prove that a particular microbe caused a person’s symptoms. The long-term goal of predicting disease risks and intervening before they appear also remains a research area requiring clinical validation.
The company says it has published four scientific papers, including a study involving infants, and plans to support additional research on adults. It will allocate $5 million to make its tests and data available to researchers and clinical partners. The significance of the round, therefore, lies in moving the test from a direct-to-consumer product toward a data and research infrastructure connected to healthcare providers. However, the value of this health data will remain tied to its ability to prove that microbiome-guided interventions actually improve outcomes, rather than merely identifying microbial differences.