Tiny Health, a microbiome intelligence platform focused on scientifically validated gut and vaginal microbiome testing across the lifespan, announced that it has raised an oversubscribed $33 million Series B round led by B Capital, bringing the company’s total funding to $46 million.
The round also included participation from existing investors Spero, The Venture City, and Overwater Ventures, along with new investors Black Opal Ventures, Denver Ventures, Alumni Ventures, Gaingels, and Pari Passu Ventures.
Tiny Health plans to use the new funding to advance clinical research and interventional studies, expand healthcare practitioner education, and scale Powered by Tiny, its B2B platform. The company is also accelerating development of its consumer technology, including TinyAI, which Tiny Health describes as an AI system trained on nearly 200,000 microbiome profiles to provide personalized, science-backed guidance connected directly to a user’s results.
The company is expanding its platform beyond early-life health and into longevity and healthy aging, with new tools including Gut Microbiome Age, Gut Resilience, and health condition associations designed to help users understand the microbiome as part of a broader biological system.
Founded in 2020 and launched in 2022, Tiny Health initially developed a gut microbiome test for babies using shotgun metagenomic sequencing, along with gut and vaginal microbiome testing for mothers.
The company’s early focus was based on the importance of the first 1,000 days of life, a period when the gut microbiome is particularly malleable and can play an important role in immune development and chronic conditions including metabolic and allergic diseases.
Tiny Health has since broadened its platform across the lifespan. The company now serves nearly 200,000 customers and more than 5,000 healthcare practitioners across independent practices, hospital systems, longevity clinics, consumer health companies, and precision medicine organizations.
Adult testing has now surpassed pediatric testing in volume, reflecting Tiny Health’s expansion beyond its original focus on infant and maternal health.
Tiny Health said its platform is designed around the idea that there is no single universal definition of a “healthy” microbiome, particularly among older children and adults.
Instead, the company evaluates functional characteristics such as microbial diversity, resilience, metabolic markers, immune markers, and potentially pathogenic organisms to provide a more detailed picture of microbiome health.
Using shotgun metagenomics, Tiny Health said it can detect microbes across more than 120,000 genomes down to the strain level, while identifying functional characteristics including metabolic capacity, immune markers, resilience, and potentially pathogenic organisms.
The company said this approach provides a more comprehensive view than traditional stool cultures and narrower qPCR panels.
Tiny Health also owns its full bioinformatics pipeline, which was built internally by PhD microbiologists, giving the company direct control over the analysis and interpretation of its microbiome data.
The company has published four scientific papers to date. Its 2025 randomized controlled trial published in Pediatric Allergy and Immunology found that targeted microbiome interventions reduced infants’ odds of developing eczema by 83%, according to Tiny Health.
Tiny Health has also completed recruitment for a second, larger randomized controlled trial intended to build on that work.
The company is expanding its research into additional conditions including inflammatory bowel disease, Alzheimer’s disease, and oncology drug response, using what it describes as one of the world’s largest longitudinal microbiome datasets.
Tiny Health’s enterprise platform, Powered by Tiny, grew fourfold last year and now works with dozens of partners across healthcare and precision health.
Partners include Fullscript, Joi + Blokes, Resbiotic, Siphox, Nia Health, Mayo Health’s Executive Health and Longevity Clinic, Allina Health, Atria, and Superpower. Tiny Health also collaborates with academic institutions including Stanford Medicine, Mount Sinai, and Massachusetts General Hospital.
The Series B financing will support Tiny Health’s effort to make microbiome data more measurable and actionable across different stages of life while building additional clinical evidence around the relationship between the microbiome, immune health, metabolism, and chronic disease.
KEY QUOTES:
“We founded Tiny Health because the science is so impactful, the need is urgent, and no one else was building for the whole lifespan. What started as a solution for my own family has become the infrastructure for an entire industry. This Series B round solidifies Tiny Health as the industry leader and propels microbiome science as the foundational layer for the next frontier of medicine. We are setting that standard through scientific publications, transparency, and vigorous validation.”
Cheryl Sew Hoy, CEO and Founder of Tiny Health
“What we’re seeing in literature and in our proprietary data is that chronic health conditions aren’t just about having opportunistic pathogenic microbes. In many cases, they’re also associated with missing core beneficial functions. If we focus only on getting rid of the ‘bad’ microbes without restoring the ‘good’ microbes, we may end up with a gut community that is less resilient. Tiny Health’s platform educates consumers and practitioners about what nutrition and lifestyle modifications will help replenish that beneficial flora that’s so important for immune health.”
Kimberley Sukhum, PhD, Chief Science Officer at Tiny Health
