Chapters
Take the gut check and we will sort the chapters by relevance for you.
Gut barrier
The gut lining as the border between gut contents and the body. 1 chapter – expand
- Level:Intermediate Gut and endurance sport: runner’s gut, cramps and what helps During long, hard sessions the gut gets less blood, briefly becomes leakier and digests less well. Why runners are hit more often, what heat and ibuprofen have to do with it, and why the gut can be trained. ExerciseDiarrhoeaFODMAPMedicationNutrientsBloating Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
Opportunistic pathogens
Germs that only become a problem when the balance is off. 4 chapters – expand
- Level:Intermediate After antibiotics: C. difficile and faecal transplants A germ that can take over after antibiotics, and a treatment that works better than any drug. AntibioticsFaecal transplantProbioticsDiarrhoeaGut infectionsBile acidsToxins and mould Established How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Intermediate When the gut does not settle after an infection Stomach bug, food poisoning, traveller's diarrhoea: why symptoms sometimes stay. Gut infectionsIBSDiarrhoeaBile acids Well supported How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Intermediate Parasites in the gut: worms, protozoa and Blastocystis Which parasites make you ill, which are probably harmless lodgers and how to detect them reliably. ParasitesGut infectionsDiarrhoeaTests and diagnostics Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
- Level:Intermediate Saccharomyces boulardii: the probiotic yeast Why a yeast survives antibiotics, what it is proven to help with, and when it can become dangerous. ProbioticsAntibioticsDiarrhoeaGut infections Well supported How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
Microbial diversity
Why many different species keep the gut stable. 1 chapter – expand
- Level:Intermediate Spore-forming bacteria: Bacillus and co. as probiotics How probiotics in spore form survive stomach acid, what they do in the gut and where the evidence ends. ProbioticsIBSDiarrhoea Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
Gut-brain axis
How stress, sleep and nerves steer digestion. 2 chapters – expand
- Level:Intermediate Hormones, the cycle and the gut Why gut symptoms change around your period, in pregnancy and at menopause, and when endometriosis or the thyroid may be behind them. IBSConstipationDiarrhoea Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Beginner Abdominal pain and cramps: where the pain comes from Cramp, fullness or stabbing: why the gut signals pain, when it is harmless and when it needs checking. IBSBloatingConstipationDiarrhoeaStressExercise Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
Digestive function
Stomach acid, bile and enzymes as groundwork for the gut. 5 chapters – expand
- Level:Intermediate Bile acids: when bile causes diarrhoea Primary and secondary bile acids, the role of gut bacteria and why antibiotics can shift the balance. Bile acidsDiarrhoeaIBSTests and diagnostics Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
- Level:Intermediate Life without a gallbladder: diarrhoea, fat and symptoms after surgery Gallbladder removal is one of the most common operations, and most people do well afterwards. Why some get diarrhoea, what lies behind post-cholecystectomy syndrome and why cutting the sphincter usually does not help. Bile acidsDiarrhoeaTests and diagnostics Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
- Level:Beginner Diarrhoea: understand it, place it and react the right way Watery, urgent, acute or chronic: the four mechanisms, the most common causes and when it needs checking by a doctor. DiarrhoeaIBSFODMAPBile acidsGut infectionsTests and diagnosticsTravel Well supported How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Intermediate Nutrient deficiency in gut problems: when food no longer arrives Why gut symptoms can leave you short of iron, vitamin B12, vitamin D, the fat-soluble vitamins and zinc, how to read blood results correctly and when supplements really help. NutrientsVitamins and fatty acidsDiarrhoeaTests and diagnosticsBody weight Well supported How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Beginner When the supplement itself is the problem: iron, magnesium, excipients and more People struggling with their gut often take several supplements at once. Some of them trigger exactly the symptoms they are meant to relieve. Which products typically cause diarrhoea, constipation or bloating, what tablets contain besides the active ingredient, and how to find the culprit. MedicationVitamins and fatty acidsNutrientsProbioticsSweetenersBloatingDiarrhoeaConstipation Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
Small intestine colonisation
When bacteria grow where few belong. 2 chapters – expand
- Level:Expert Where the small intestine meets the colon: ileum, valve and caecum At the end of the small intestine, the gut switches from few to very many bacteria. What the last stretch of small intestine does, how the valve separates the two worlds, and how this transition can be disturbed. Bile acidsDiarrhoeaInflammationTests and diagnostics Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Expert Hydrogen sulfide and methane: the other gases in the gut Methane is linked to constipation, hydrogen sulfide to diarrhoea. Which microbes produce them, what a three-gas breath test can and cannot show, and what to make of low-sulfur diets and bismuth. ConstipationDiarrhoeaBloatingTests and diagnosticsAntibiotics Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
Immune system and inflammation
The gut as the body's largest immune organ. 3 chapters – expand
- Level:Intermediate Histamine intolerance: much searched, little proven Headache after red wine, diarrhoea after cheese? What is known about histamine and what is not. HistamineFermented foodsAlcoholTests and diagnosticsDiarrhoea Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. Community
- Level:Intermediate PEA (palmitoylethanolamide): the body's own inflammation brake in a capsule A fatty substance the body makes itself to calm mast cells and inflammation. As a supplement it is taken for gut and nerve pain. What studies show and where they are thin. IBSInflammationHistamineDiarrhoea Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Level:Intermediate Crohn’s disease and ulcerative colitis: understanding inflammatory bowel disease In Crohn’s disease and ulcerative colitis, the immune system permanently attacks the gut wall. What distinguishes the two, what role genes, smoking, antibiotics and gut microbiota play, why early treatment matters, and what diet, probiotics and faecal transplants really achieve. InflammationDiarrhoeaTests and diagnosticsMedicationAntibioticsNutrientsProbioticsFaecal transplantMediterranean diet Established How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.