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
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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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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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
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