The Evidence-Based
Probiotic Strain Guide

Lactobacillus rhamnosus GG is the world's most studied probiotic strain, with over three decades of clinical research backing its ability to keep your gut resilient during and after antibiotic treatment. Think of it as your digestive system's personal bodyguard — one that survives the harsh acid of your stomach, clings to the gut wall, and holds the line against the bad guys. Whether you're dealing with travel tummy, antibiotic fallout, or unpredictable IBS flares, this strain has a track record that speaks for itself.

Unlike every other probiotic on this site, Saccharomyces boulardii CNCM I-745 isn't a bacterium at all — it's a beneficial yeast, and that one difference makes it uniquely powerful. Because antibiotics only target bacteria, this probiotic sails right through a course of antibiotics completely unaffected, actively working to protect your gut while the medication does its job. It's one of the most extensively researched probiotics in the world for fighting antibiotic-associated diarrhea, traveler's diarrhea, and the dangerous gut infection caused by C. difficile.

If bloating and gut pain have taken over your life, Bifidobacterium infantis 35624 is one of the most rigorously researched probiotic strains on the planet specifically for IBS relief. It works by calming the inflammatory signals in your gut — like a skilled peacekeeper quieting a riot — so your digestive system can finally get back to normal. Clinical research consistently singles it out as the probiotic of choice for people struggling with abdominal discomfort, excessive gas, and unpredictable bowel habits.

Lactobacillus acidophilus NCFM is one of the most researched probiotic strains on the planet — and for good reason. It's clinically studied to help ease the bloating, cramping, and unpredictable bathroom trips that come with IBS and lactose intolerance. Think of it as a trusted daily partner for a calmer, more comfortable gut.