The Science Behind Flore

Last updated: March 2026

Flore represents a fundamental shift in how probiotics are developed and delivered. Rather than offering a single formula to millions of different people, Flore creates a unique, custom-manufactured probiotic formulation for every individual based on their specific microbiome data, health history, symptoms, and goals. This page explains the science, the technology, the evidence, and the clinical infrastructure that makes this possible.

The Flore Formulation Engine

At the core of Flore is a proprietary formulation engine that has been refined over more than two decades of microbiome research. This engine processes an extraordinary depth of biological data to produce a probiotic formula tailored to each individual.

The numbers define the scope of the system:

• 352 biomarkers are analyzed for each individual, covering microbial composition, metabolic markers, inflammatory indicators, and digestive function parameters.
• 23,000+ microbial species are mapped in Flore's reference database, enabling precise identification of what is present, what is missing, and what is overrepresented in each person's gut ecosystem.
• 209 health conditions are cross-referenced against microbial patterns, allowing the formulation engine to connect an individual's symptoms and diagnoses to specific microbiome imbalances.

The formulation library itself includes 68+ clinically validated probiotic strains and 40+ prebiotics, each with documented mechanisms of action and known interactions. The engine selects from this library to build a multi-strain, multi-prebiotic formula that addresses the individual's specific needs. This is not a selection from pre-made blends. Every formula is built from scratch and custom-manufactured at Flore's facility in Joliet, Illinois.

40,000+ Formulations: Why Real Human Outcomes Data Matters

Flore has created more than 40,000 personalized probiotic formulations to date, producing a dataset of real human outcomes that is unmatched in the probiotic industry. Across all health systems, Flore maintains a 94.2% success rate, measured by patient-reported outcomes and clinician assessments.

This dataset is significant for several reasons. Most probiotic research is conducted in controlled laboratory settings (in vitro) or in animal models (typically mice). While these studies can suggest mechanisms, they often fail to translate to human outcomes. Mouse microbiomes differ fundamentally from human microbiomes. Laboratory conditions do not replicate the complexity of a living human gut. And single-strain studies rarely capture the multi-strain, multi-prebiotic interactions that determine real-world efficacy.

Each formulation outcome feeds back into the engine, making subsequent formulations more precise. This creates a compounding advantage: the more formulations Flore creates, the better the engine becomes at predicting which combinations of strains and prebiotics will produce the best results for a given microbiome profile.

Peer-Reviewed Research: The ASD Microbiome Study

Flore's approach is validated by peer-reviewed research published on PubMed. The study, available at PMC11097633, examined the impact of personalized probiotic formulations on individuals with Autism Spectrum Disorder (ASD) and represents one of the largest studies of its kind.

Study Design and Participants

The study enrolled 296 ASD participants along with 123 neurotypical controls. Of the ASD participants, 170 completed the full intervention protocol. This is a substantially larger cohort than most probiotic intervention studies, which typically involve 20 to 60 participants.

Key Findings

• 62% of ASD participants reported overall improvement across multiple domains after receiving personalized probiotic formulations.
• More than 50% showed improvement in language, cognition, and gastrointestinal symptoms, representing meaningful gains across the domains most affected in autism.
• Significant increase in microbiome diversity was observed, indicating that the personalized formulations successfully shifted the gut ecosystem toward a healthier, more diverse state.
• Significant reduction in GI symptoms as measured by the Gastrointestinal Symptom Rating Scale (GSRS), a validated clinical instrument for assessing digestive health.

Microbiome Differences in ASD

The study also characterized how ASD microbiomes differ from neurotypical controls. ASD participants showed higher levels of pathogenic bacteria, including Shigella, Klebsiella, and Clostridium, and lower levels of beneficial bacteria, particularly Faecalibacterium, which is known for its anti-inflammatory properties and its role in producing butyrate, a critical short-chain fatty acid for gut barrier integrity.

These findings explain why generic, one-size-fits-all probiotics often fail for individuals with ASD. The microbiome imbalances are specific and complex, requiring formulations that address the unique microbial patterns present in each individual.

Whole-Genome Sequencing Technology

In 2026, Flore Inc. raised capital and acquired Sun Genomics, gaining access to advanced whole-genome sequencing technology for microbiome analysis. Sun Genomics had attracted venture funding from notable investors including Danone Manifesto Ventures, SOSV/IndieBio, and Pangaea Ventures, reflecting the quality and potential of the technology.

Whole-genome sequencing (WGS) represents the most comprehensive method for analyzing the gut microbiome. Unlike 16S rRNA sequencing, which only identifies bacteria at the genus level by reading a single gene, WGS reads the entire genetic content of every organism in a sample. This provides:

• Species-level and strain-level identification, which is critical because different strains of the same species can have vastly different effects on health.
• Functional gene analysis, revealing what the microbiome is capable of doing, not just what organisms are present.
• Detection of antibiotic resistance genes, virulence factors, and metabolic pathways that inform formulation decisions.
• Higher sensitivity for detecting low-abundance organisms that may be clinically significant but missed by less comprehensive methods.

This technology integrates directly into Flore's formulation engine, providing the deepest possible view of each individual's gut ecosystem and enabling the most precise formulations.

Clinician Monitoring: What It Means and Why It Matters

Flore is the only personalized probiotic company where every formula is clinician-monitored. This is not a marketing claim attached to an occasional consultation. It is a structural feature of how Flore operates.

Here is what clinician monitoring means in practice:

• Every formulation is reviewed by a clinician before it is manufactured. This review considers the individual's health history, current medications, diagnoses, and any contraindications.
• Ongoing monitoring of patient progress allows clinicians to assess whether the formulation is producing the expected outcomes.
• Formulas are adjusted based on patient progress. If an individual responds well but has remaining symptoms, the formula can be modified. If a patient's health status changes, the formulation adapts.
• Clinical oversight ensures safety, particularly for individuals with complex health conditions, those taking medications, or those with compromised immune systems.

This clinical infrastructure is supported by Flore's HIPAA Business Associate compliance and a dedicated clinical provider portal at portal.floreclinical.com, where healthcare providers can order formulations, track patient progress, and view microbiome data.

How Formulas Are Adjusted Based on Patient Progress

Personalization does not end when a formula is manufactured. Flore's system is designed for iterative improvement. Here is how the adjustment process works:

1. Initial formulation is created based on the individual's data (symptom quiz, lab results, or both).
2. Progress monitoring captures patient-reported outcomes including changes in symptoms, energy, digestion, mood, and other health indicators.
3. Clinician review evaluates the progress data and determines whether adjustments are warranted.
4. Formula modification can include changes to strain composition, prebiotic selection, CFU counts, or the introduction of new strains to address emerging patterns.
5. Re-manufacturing produces the updated formula, which is shipped to the patient for their next cycle.

This iterative approach recognizes that the microbiome is dynamic. It changes with diet, stress, illness, medication, and time. A static formula cannot account for this. Flore's system can.

The Formulation Library: 68+ Strains and 40+ Prebiotics

Flore's formulation library is one of the most extensive in the personalized probiotic space. It includes:

• 68+ probiotic strains spanning multiple genera including Lactobacillus, Bifidobacterium, Saccharomyces, Bacillus, and others. Each strain has documented mechanisms of action, safety profiles, and evidence for specific health outcomes.
• 40+ prebiotic compounds that serve as fuel for beneficial bacteria. Prebiotics are selected to support the specific strains in each formula and to promote the growth of beneficial bacteria already present in the individual's gut.

The combination possibilities are vast. This is precisely why Flore does not use pre-made blends. The likelihood that any pre-made combination would be optimal for a given individual is extremely low. Custom manufacturing from this extensive library ensures each formula is genuinely tailored.

Frequently Asked Questions

FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. Flore products are not intended to diagnose, treat, cure, or prevent any disease. The information on this page is for educational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider before starting any new supplement regimen.