Probiotics
Live bacteria or yeasts, not a single molecule. What they do depends on the exact strain.
Evidence current to September 2026
What it's pushed for
What the research shows
Probiotics aren't one thing. The American Gastroenterological Association's 2020 guidelines recommended specific strains in only three narrow situations, such as preventing C. difficile infection during antibiotics, and noted major gaps in the evidence.
A 2025 pharmacist review found the most consistent benefits for L. rhamnosus GG and Saccharomyces boulardii, while other strains of the same species didn't reliably work.
Myth vs. fact
Myth"More strains and more billions are better."
FactNeither is supported. Matching a studied strain to a specific problem is what matters.
The detail most people miss
For people with histamine sensitivity: certain strains of L. reuteri, L. casei, and L. bulgaricus can produce histamine. Whether this matters in the body is still debated.
Who should check with a clinician first
People who are immunocompromised, critically ill, or have central lines.
What to look for on the label
Look for the full strain name, meaning the letters or numbers after the species (like "L. rhamnosus GG"). Check that the CFU count is guaranteed through the expiration date, not just "at time of manufacture."
How to read any supplement labelSources
This guide is for education, not medical advice. Supplements can interact with medications and health conditions. Talk with your clinician or pharmacist before starting, stopping, or changing anything. The Lily Perspective earns no income from any supplement brand or retailer.