Cheryl Sew Hoy, co-founder and CEO of Tiny Health, was inspired by her daughter’s eczema and allergies to explore infant gut microbiome research. After learning that early microbial exposure could influence health, she founded Austin‑based Tiny Health in 2020. The company announced a $33 million Series B round led by B Capital, bringing total funding to $46 million.

Existing investors Spero Ventures, The Venture City, Overwater Ventures, and new backers Black Opal Ventures and Alumni Ventures participated. B Capital’s Nick Whitehead joins the board. Tiny Health’s at‑home tests, which use shotgun metagenomic sequencing, have driven rapid growth: overall revenue more than doubled annually, and the B2B arm, Powered by Tiny, grew fourfold last year.

Initially focused on infant testing, the firm now serves adults as its largest segment, offering pregnancy, vaginal, and adult microbiome tests. The platform provides detailed reports and actionable lifestyle recommendations, supported by a team including Chief Science Officer Kimberley Sukhum, co‑founder Donald Koo, and Chief Medical Officer Dr. Elisa Song.