Evidence-based gut health

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Evidence-based guides on the microbiome, probiotics, IBS, leaky gut, and the science of digestive health. Written for curious people, cited from real research.

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Colorful whole foods for gut health
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Essential Reading
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Healthy eating for gut-brain connection
Gut-Brain Axis
The Gut-Brain Axis Explained: How Your Microbiome Shapes Your Mood
95% of serotonin is made in your gut. Here is the science of what that actually means for anxiety, depression, and mental clarity.
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 Fermented foods for gut health
Diet
Fermented Foods and the Microbiome: What the Science Really Shows
Kimchi, kefir, sauerkraut—ranked by clinical evidence. Which fermented foods actually move the needle on gut diversity.
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 Probiotic supplements
Probiotics
Best Probiotics by Strain and Condition: A Buyer's Guide That Actually Helps
Most probiotic labels are meaningless. Here is how to read the strains, match them to your condition, and avoid expensive placebos.
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Just Thrive Probiotic — our top-rated pick Spore-based strains that actually survive stomach acid. Independent third-party tested. Trusted by functional medicine practitioners.
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The library
All 151+ Guides
67 guides
Leaky Gut
What Is Leaky Gut and Does It Actually Exist?
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Probiotics
How to Read a Probiotic Study: Strain, Dose, Endpoint, and Who Paid for It
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Probiotics
Best Probiotics by Strain and Condition
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Gut-Brain
The Gut-Brain Axis Explained
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Diet
Foods That Destroy Your Microbiome
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Testing
How to Test Your Gut Microbiome at Home
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IBS
IBS vs IBD: What Is the Difference?
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Microbiome
Postbiotics: The Next Frontier in Gut Health
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Diet
Alcohol and the Gut Microbiome
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Digestive
Barrett's Esophagus, GERD, and the Microbiome
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Diet
Best Fiber Supplements for Gut Health
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Probiotics
Best Probiotic Brands Compared
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Probiotics
Best Probiotic for IBS
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Probiotics
Best Probiotic for Women
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Probiotics
Seed vs Garden of Life vs Thorne Probiotic
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Digestive
Bile Acid Malabsorption and Chronic Diarrhea
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Microbiome
Bile Acids and the Gut Microbiome
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IBS
Bloating: Causes and Evidence-Based Solutions
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Diet
Butyrate and Short-Chain Fatty Acids Explained
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Microbiome
Candida Overgrowth and Gut Dysbiosis
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Diet
Celiac Disease: Diagnosis and Gut Healing
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IBS
Chronic Constipation: Motility, Fiber and Treatment
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Microbiome
Circadian Rhythm and the Gut Microbiome
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Testing
Colorectal Cancer Screening: A Complete Guide
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IBD
Crohn's Disease: Microbiome, Diet and Treatment
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Diet
Dietary Fiber Types: Prebiotic, SCFA, Resistant Starch
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Diet
Digestive Enzymes: Do You Actually Need Them?
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Digestive
Diverticulitis, Diverticulosis and the Microbiome
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Diet
Elimination Diet: Food Sensitivities and Reintroduction
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Diet
Gut Reset Meal Planner: How to Structure a 30-Day Elimination Diet
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Microbiome
Fecal Microbiota Transplant (FMT) Explained
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Diet
Fermented Foods and Gut Health
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Diet
Fiber, the Microbiome and Butyrate
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IBS
Functional Dyspepsia: Causes and Treatments
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Microbiome
Gallbladder, Bile Acids and the Microbiome
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Probiotics
Garden of Life vs Thorne Probiotic: Compared
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Digestive
Gastroparesis: Delayed Gastric Emptying Explained
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Gut-Brain
The Vagus Nerve and Gut-Brain Communication
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Gut-Brain
Psychobiotics: Probiotics for Mental Health
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Microbiome
Gut Recovery After Antibiotics: A Protocol
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Microbiome
The Gut-Sleep Connection
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Microbiome
Gut Health Starter Guide for Beginners
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Microbiome
Gut Hormones, the Estrobolome and PCOS
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Microbiome
Gut Microbiome Diversity: Why It Matters
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Microbiome
What Is the Gut Microbiome?
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Gut-Brain
The Gut Microbiome and Mental Health
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Testing
Microbiome Testing: 16S rRNA and Viome Explained
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Testing
Viome vs Thryve vs Biomesight: Compared
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Microbiome
Gut Microbiome and Weight Loss
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Metabolic
Gut Microbiome and Type 2 Diabetes
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IBS
Gut Motility and Constipation
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Microbiome
Akkermansia Muciniphila and the Gut Barrier
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Diet
Butyrate, Colonocytes and the Role of Resistant Starch
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Microbiome
Primary vs Secondary Bile Acids: A Deep Dive
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Diet
Celiac Disease, Villi Damage and Gut Healing
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Digestive
Eosinophilic Esophagitis (EoE) and Elimination Diet
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Digestive
Exocrine Pancreatic Insufficiency and Enzyme Replacement
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Gut-Brain
Vagus Nerve, Serotonin and Microbiome Mood Effects
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IBD
Crohn's Biologic Therapy: TNF, Vedolizumab and More
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Gut-Brain
The Gut-Brain Connection: Your Second Brain
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Gut-Brain
Gut Microbiome and Mental Health: The Connection
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Microbiome
Candida Overgrowth in the Gut: Full Guide
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IBS
Constipation and Gut Health
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IBS
Constipation: Magnesium, Fiber and Motility Protocols
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Microbiome
Microbiome Changes That Support Weight Loss
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Gut-Brain
Gut-Brain Axis, Microbiome and Mood Regulation
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Gut-Brain
How the Gut Makes Serotonin
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Microbiome
Alpha vs Beta Diversity: Reading Your Microbiome Report
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Explore by topic
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Microbiome
Bacteria, fungi, diversity
Probiotics
Strains, brands, conditions
Leaky Gut
Permeability, zonulin, healing
IBS & IBD
Crohn's, colitis, SIBO
Diet & Food
Fiber, fermented foods, elimination
Testing
At-home kits, interpretation, labs
Buyer's guides

Before you buy, read the evidence.

Independent guides graded by what the trials show, including the categories we tell you to skip. Some links are affiliate links; see our affiliate disclosure.

Ritual Synbiotic+ Review Seed DS-01 Daily Synbiotic Review Best Probiotic Subscription Services for 2026 Viome Gut Intelligence Test Review Best Probiotics for a New Year Gut Reset Best Fiber Supplements for a January Reset Dry January, Done Gut-Friendly Best Digestive Enzymes After Holiday Overeating Best Gut Health Gifts 2026 Probiotic & Digestive Holiday Survival Kit 2026 Best Fiber Supplements for Holiday Overeating 2026 Black Friday Gut Health Deals 2026 Best Stool Test Kits Best Water Filters for Gut Health Best Sous Vide Machines Best Yogurt Makers Best Low-FODMAP Protein Powder for IBS & SIBO Best Fiber Supplements for Gut Health — Science-Ranked Best Magnesium Supplements for Constipation Best Electrolyte Powders
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