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Rapamycin extends mouse lifespan 9–14%
NAD+ precursors reverse aging in humans
Blue-light glasses improve sleep quality
Walking 10 min after meals blunts glucose
Verdict change — caffeine half-life downgraded

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215 - The gut-brain connection | Michael Gershon, M.D. — Whalespan

Content›Video›215 - The gut-brain connecti…

215 - The gut-brain connection | Michael Gershon, M.D.

Peter Attia2h 13m · 2022-07-25

Claims Made

201

Claims Supported

161

Support Rate

80%

Support rate

161 of 201 claims supported

161 supported40 partial / not

Claims from this content

157

✓Well SupportedRoux-en-Y gastric bypass surgery is an effective treatment for obesity by disrupting the endocannabinoid pathway signaling between the brain and gut.✓Well SupportedMechanical sensory information from the gut is detected by mechanoreceptors and transmitted to the brainstem via the vagus nerve.✓Well SupportedPressure receptors in the gut signal to the brain to regulate food consumption.✓Well SupportedThe stomach and small intestine should ideally be free of bacteria before reaching the colon for proper nutrient absorption.Partially Supported

More from Peter Attia

Peter Attia on Zone 2 Cardio

Peter Attia on Rapamycin (with Matt Kaeberlein)

Attia walks back the clinic protocol: too aggressive for healthy adults

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A. Volkovreader

4h

Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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◐

Varicella-zoster virus remains latent in neurons and can reactivate as shingles.

◐Partially SupportedTaking probiotics during antibiotic treatment may help maintain a healthy gut microbiome and its functions, such as short-chain fatty acid production.

✓Well SupportedGut bacteria digest dietary fiber, producing short-chain fatty acids that are essential energy sources for colonic epithelial cells.

◐Partially SupportedThe gut possesses an intrinsic nervous system, termed the 'second brain,' capable of functioning and controlling reflexes independently of the central nervous system.

✓Well SupportedFecal transplants are being used to treat obesity by transplanting the gut microbiome of thin people into obese individuals, leading to weight loss.

◐Partially SupportedAutism involves the enteric nervous system, potentially contributing to gastrointestinal symptoms like constipation, diarrhea, food sensitivities, and allergies.

✕Not SupportedDietary cleanses are not beneficial for the microbiome and may not be well-understood.

✓Well SupportedExtrinsic innervation of the gut includes nerves from the central nervous system and the sympathetic nervous system.

◐Partially SupportedTight junctions between epithelial cells prevent material from passing through the space between cells, acting as a plug.

◐Partially SupportedSerotonin in the gut is crucial for sensing pain, triggering nausea, and transmitting signals from the gut to the brain.

◐Partially SupportedThe gut has transporters that can absorb amino acids, oligopeptides, and tripeptides into the intestinal wall.

◐Partially SupportedReactivation of VZV in the enteric nervous system can lead to gastrointestinal diseases such as pseudo-obstruction or perforation.

◐Partially SupportedA mouse model with a mutation in the serotonin transporter (SERT) exhibits a 'super SERT' phenotype leading to serotonin deficiency and autism-like behaviors.

◐Partially SupportedThe stomach performs significant mechanical digestion by breaking down food into sub-millimeter particles using contractions and acid.

◐Partially SupportedClostridium difficile is a normal component of the human gut microbiome and is controlled by other bacteria.

✓Well SupportedThe number of bacteria in the colon is roughly equal to the number of human cells in the body.

✓Well SupportedGhrelin secretion is turned down by the presence of nutrients.

◐Partially SupportedThe stomach senses nutrients and regulates its emptying rate, signaling the brain to induce satiety.

◐Partially SupportedThe presence of alpha-1 antitrypsin in stool indicates a problem, likely related to gut permeability.

◐Partially SupportedAllergies causing leaky gut are not always food-specific; other triggers like bee stings or toxins can also cause tight junctions to open.

◐Partially SupportedIf tight junctions in the gut lining open, protein can enter the GI tract, leading to exudative enteropathy and severe edema.

◐Partially SupportedThe small intestine's motility and limited bacterial entry help maintain low bacterial counts.

✓Well SupportedAntibiotics have significant negative impacts on the microbiome.

✓Well SupportedThe gut epithelial barrier replaces itself within five to seven days and can heal if the irritant is removed.

◐Partially SupportedKnocking out the serotonin transporter (SERT) in mice results in excess gut nerve cells.

◐Partially SupportedLow serum albumin levels can indicate a leaky gut.

◐Partially SupportedThe epithelial lining of the intestines is replaced approximately every week through a process involving stem cells.

◐Partially SupportedShingrix, a purified protein vaccine for varicella-zoster virus, is more effective than the live attenuated vaccine Zostavax.

◐Partially SupportedShingles can lead to postherpetic neuralgia, a chronic pain condition.

◐Partially SupportedThe enteric nervous system was discovered around the time of the American Civil War.

◐Partially SupportedBacterial classes in the colon include Firmicutes, Bacteroides, Actinobacteria, and Proteobacteria.

◐Partially SupportedGut bacteria can activate enteroendocrine cells to release serotonin, which communicates with the brain.

◐Partially SupportedEating protein and fat leads to reaching satiety sooner compared to eating only salt and sugar.

◐Partially SupportedThe superior mesenteric artery supplies the midgut, extending to the mid-transverse colon.

◐Partially SupportedUnder conditions of bile salt or pancreatic enzyme deficiency, exogenous fats can reach the colon and be metabolized by bacteria, leading to fatty stools.

◐Partially SupportedInsoluble fiber is important for absorbing toxins, promoting motility, and providing substrate for gut bacteria to produce short-chain fatty acids.

◐Partially SupportedFecal microbiota transplantation is a life-saving treatment for C. difficile infections that do not respond to oral vancomycin.

◐Partially SupportedFecal transplantation for C. difficile requires carefully screened stool to avoid introducing potentially dangerous organisms.

◐Partially SupportedGerm-free mice have underdeveloped spleens and Peyer's patches, indicating a compromised immune system.

✕Not SupportedThe 'leaky gut' hypothesis lacks evidence as a cause for autism spectrum disorder.

◐Partially SupportedEnzymes like trypsin are genetically programmed to cut proteins at specific amino acid sequences.

◐Partially SupportedThe vagus nerve primarily carries homeostatic information to the brain and has a limited role in transmitting pain signals from the gut.

◐Partially SupportedThe liver is a major metabolic center that processes nutrients absorbed by the gut, such as converting fatty acids into chylomicrons.

◐Partially SupportedThe liver receives oxygen from the hepatic artery in addition to blood from the gut's portal system.

◐Partially SupportedSaccharomyces, a yeast-derived product, restores the GI system after antibiotic treatment.

◐Partially SupportedThe primary treatment for cholera is supportive care to prevent dehydration, involving intravenous and oral fluid replacement.

◐Partially SupportedActivia, containing Bifidobacterium animalis, survives stomach acid and reaches the GI tract.

◐Partially SupportedMost fibers excited by increased pressure in the gut are pain fibers that relay signals to the brain via the spinal cord.

◐Partially SupportedThe Shingrix vaccine can cause significant side effects, with younger individuals experiencing more pronounced reactions.

◐Partially SupportedThe immune system can fight off cholera if given sufficient time, with treatment focused on supporting hydration status.

◐Partially SupportedApproximately three million people die from cholera annually, with the majority of cases occurring in Asia and Africa.

◐Partially SupportedGhrelin is a gut hormone that promotes food intake, acting in opposition to hormones that decrease food absorption.

◐Partially SupportedGerm-free animals, raised without any microbial contact, are born via cesarean section and fed sterile food.

◐Partially SupportedThe small intestine neutralizes stomach acid, benefiting from the reduced number of organisms entering it.

✕Not SupportedCommercial gut microbiome tests may be driven by a business model of selling supplements rather than scientific validation.

◐Partially SupportedVZV reactivation is associated with aging and immune suppression, as seen in early HIV patients.

◐Partially SupportedAlpha-1 antitrypsin deficiency can lead to vascular and lung disease due to excessive digestive action damaging these organs.

◐Partially SupportedThe colon absorbs the final ~100ml of water daily, which is crucial for maintaining body fluid content.

◐Partially SupportedThe colon is more susceptible to neoplasia (cancer) than the small intestine due to frequent cell turnover and higher exposure to toxins from the microbiome and gut contents.

◐Partially SupportedCholera toxin causes sodium absorption to turn into chloride secretion, leading to rapid water loss and dehydration.

◐Partially SupportedThe large intestine's microbiome is much larger and its contents remain longer than the small intestine's, increasing toxin exposure.

◐Partially SupportedSSRIs may be used during pregnancy despite potential risks to the child, as depression itself is a potentially lethal illness.

◐Partially SupportedSNRIs inhibit both serotonin and norepinephrine reuptake and have similar effects to SSRIs.

◐Partially SupportedLeaky gut can be assessed using oral peptides, fluorescein, dyes, or non-absorbable sugars.

◐Partially SupportedShort-chain fatty acids produced by gut bacteria are absorbed and can enter the body to provide energy.

◐Partially SupportedIn utero exposure to SSRIs in mice leads to an excess of nerve cells in the gut, causing defective gut motility.

◐Partially SupportedPaneth cells in the small intestine produce defensins, which help keep the lumen near-sterile.

◐Partially SupportedGerm-free mice exhibit underdeveloped gut nerve cells, motility, and lining compared to normally born mice.

◐Partially SupportedPostherpetic neuralgia is a pathological pain originating from within the central nervous system, making it difficult to treat.

◐Partially SupportedProbiotic pills do not necessarily require refrigeration to survive.

◐Partially SupportedFecal transplantation in humans carries inherent dangers.

◐Partially SupportedThe major plexuses of the enteric nervous system are the submucosal plexus and the myenteric plexus, which communicate with each other and the central nervous system.

◐Partially SupportedAdding sugar to oral rehydration fluids for cholera patients significantly saves lives by leveraging the small intestine's ability to absorb glucose.

✕Not SupportedPeter Attia believes that most commercially available gut microbiome tests and supplements are ineffective or nonsensical.

✕Not SupportedHome-brewed fecal transplants or those given between spouses without proper screening have led to patient deaths.

◐Partially SupportedOral vancomycin is a first-line treatment for C. difficile infections because it is not absorbed systemically and acts locally in the gut.

◐Partially SupportedCreating synthetic microorganisms for fecal transplantation is not currently feasible because many gut organisms cannot be cultured in vitro.

◐Partially SupportedCurrent home gut microbiome tests lack the necessary resolution to determine an individual's microbiome composition and its impact on conditions like anxiety or body form.

◐Partially SupportedThe celiac artery supplies the stomach, first part of the duodenum, pancreas, liver, and gallbladder.

◐Partially SupportedThe central nervous system can influence gut function, causing sensations like butterflies or tension-induced diarrhea, and can also lead to constipation.

◐Partially SupportedReactivation of VZV in the esophagus can cause achalasia, leading to difficulty swallowing.

◐Partially SupportedThe central nervous system directly senses the rate of change of glucose, not just the absolute level.

◐Partially SupportedPain in the gut is primarily a response to dilatation or pressure, and cutting the inside of the gut does not cause pain.

◐Partially SupportedAntibiotics are used in agriculture for growth promotion and infection prevention, leading to human exposure.

◐Partially SupportedBleeding into the gastrointestinal tract results in blood loss from the body.

◐Partially SupportedGerm-free mice can develop an immune system if exposed to bacteria after birth.

◐Partially SupportedThe GI tract lining allows only sterile nutritional building blocks to cross from the lumen into the body.

◐Partially SupportedGastric bypass surgery triggers satiety signals by causing small particles to enter the small intestine.

◐Partially SupportedThe immune system cannot eradicate latent varicella-zoster virus within nerve cells because it cannot detect it there.

◐Partially SupportedCholera causes dehydration through sodium absorption blockage and chloride secretion, leading to death within approximately four hours if untreated.

◐Partially SupportedThe enteric nervous system can function autonomously, isolated from the brain and spinal cord.

◐Partially SupportedCholera outbreaks have occurred in the Western Hemisphere, spreading from Peru to New Jersey.

◐Partially SupportedThe frequency of VZV-induced gastrointestinal or esophageal diseases is currently unknown.

◐Partially SupportedSolids delay gastric emptying until particles are ground down to less than one millimeter in diameter.

◐Partially SupportedSmall peptides, if absorbed, would not be able to cross the blood-brain barrier or pass the liver.

◐Partially SupportedPeptic ulcer disease is primarily caused by Helicobacter pylori, not solely by stress.

◐Partially SupportedCutting the vagus nerves did not resolve peptic ulcer disease, indicating the gut's functional independence.

◐Partially SupportedThe stomach empties slower after consuming protein and fat compared to saline or sugar meals.

◐Partially SupportedAccurate gut microbiome analysis requires species-level resolution to enable actionable insights.

◐Partially SupportedFermented foods containing Bifidobacterium animalis can be valuable probiotics that survive stomach acid and reach the gut.

◐Partially SupportedCow's milk can contain penicillin due to agricultural industry practices.

◐Partially SupportedA balanced diet with adequate nutrients and fiber is optimal for gut flora maintenance.

◐Partially SupportedGut bacteria synthesize essential vitamins, such as vitamin K, which is crucial for blood clotting.

◐Partially SupportedSome microbiome tests, like those from Hologuard, are better suited for cancer detection.

◐Partially SupportedFiber can absorb toxins, potentially decreasing long-term carcinogenic effects.

✕Not SupportedDietary cleanses that involve drinking large amounts of water with pepper and nutrients, sometimes supplemented with enemas, may lead to electrolyte imbalance.

◐Partially SupportedFiber and polysaccharides are important nutrients for fueling gut bacteria.

◐Partially SupportedFecal transplants may be effective for anxiety.

◐Partially SupportedCologuard is effective at detecting GI cancers but is not a substitute for colonoscopy.

◐Partially SupportedThe central nervous system can communicate stress to the gut via the vagus nerve.

◐Partially SupportedSerotonin in the gut is primarily made by enteroendocrine cells and secondarily by nerve cells.

◐Partially SupportedInterference with tight junctions can allow material to move between the gut lumen and the body.

◐Partially SupportedLoss of gut epithelial serotonin impairs brain signaling and weakens the peristalsis reflex.

◐Partially SupportedSSRIs can initially speed up gut motility and cause nausea, but may lead to long-term constipation due to receptor desensitization.

◐Partially SupportedDuring development, serotonin acts as a growth factor for nerve cells in the gut, and its absence leads to too few neurons and impaired function.

◐Partially SupportedMilder forms of leaky gut may allow toxins and microorganisms to enter the body without causing a significant drop in serum albumin.

◐Partially SupportedDr. Mike Gershon's research focuses on the neural control of the gastrointestinal tract and the role of serotonin in the gut.

◐Partially SupportedSome bacteria, like Clostridia, can be both harmful and protective.

◐Partially SupportedGastric bypass surgery triggers satiety signals by causing the stomach to release small particles that simulate an emergency response, leading to reduced food intake.

◐Partially SupportedAdministering SSRIs to pregnant mice during fetal development can result in an abnormal nervous system in the offspring.

◐Partially SupportedColonizing germ-free mice with bacteria from lean mice results in lean mice, while colonization with bacteria from fat mice results in fat mice.

◐Partially SupportedMinimizing calorie intake from liquids, including alcohol, is recommended for weight loss.

◐Partially SupportedGut bacteria appear to regulate mood and obesity.

◐Partially SupportedPaneth cells in the gut release antibacterial proteins and nurse stem cells for epithelial regeneration.

◐Partially SupportedExperiments with fecal transplants in humans are difficult due to complexity and inability to control all variables.

◐Partially SupportedColonoscopy preparation does not significantly alter gut flora in a way that prevents it from returning to normal quickly.

◐Partially SupportedBifidobacterium animalis requires refrigeration because it is found in yogurt-based Activia.

◐Partially SupportedPrebiotics enable the body to grow beneficial organisms, while probiotics are consumed directly.

◐Partially SupportedContraction of the circular inner muscle layer shrinks the gut lumen, while contraction of the longitudinal muscle layer shortens the gut.

◐Partially SupportedConsuming up to two cups of Activia daily can accelerate the GI tract.

◐Partially SupportedThe immune system recognizes peptides of nine to eleven amino acids.

◐Partially SupportedAmino acids and fatty acids can suppress ghrelin secretion.

◐Partially SupportedAntibiotics are not effective against cholera.

✕Not SupportedThe hypothesis that gluten-containing material can produce opiate-like products in the digestive tract, which are then absorbed and cause autism in children with immature nervous systems, is incorrect.

✕Not SupportedCommercial home gut microbiome testing kits often provide reports with insufficient resolution for clinical decision-making.

◐Partially SupportedAntibiotics used to treat C. difficile infections can eliminate beneficial gut bacteria, allowing C. difficile to proliferate.

◐Partially SupportedThe large intestine conserves sodium by absorbing it and secreting potassium, with water following sodium absorption.

◐Partially SupportedPaneth cells have a lifespan of approximately three weeks.

◐Partially SupportedAbout 95% of the body's serotonin is produced in the gut by enterochromaffin cells, while the brain produces only about 2-3%.

◐Partially SupportedSerotonin in the gut plays a significant role in pain sensation and digestive processes.

◐Partially SupportedGut-brain communication in appetite regulation involves stomach distension, the rate of rise of blood glucose, and gut hormones like cholecystokinin.

◐Partially SupportedThe enteric nervous system, with over 100 million nerve cells, plays a primary role in gut control, significantly outnumbering extrinsic CNS nerves.

◐Partially SupportedThe gut has a nocturnal cleaning process that propels contents through the intestines during sleep.

◐Partially SupportedThe gut exhibits behaviors including propulsion, cessation of movement, mixing, and a nocturnal cleaning process.

◐Partially SupportedGut hormones like leptin and cholecystokinin can directly affect the CNS via transporters in brain blood vessels.

◐Partially SupportedSympathetic nerves can slow gut motility to prevent defecation during escape responses.

✕Not SupportedCommercial gut microbiome tests lack the resolution to provide actionable information.

◐Partially SupportedA child can develop a penicillin allergy at age two, even without prior exposure, if exposed to penicillin through cow's milk contaminated by agricultural practices.

◐Partially SupportedProbiotics are organisms with beneficial effects, while prebiotics are materials that enable the growth of beneficial organisms.

◐Partially SupportedColoGuard is a valuable tool in areas with limited access to colonoscopy or where there is hesitancy towards the procedure.

◐Partially SupportedSerotonin in the brain is responsible for happiness and makes life worthwhile.

◐Partially SupportedSSRIs prevent serotonin reuptake in the brain, increasing its availability.

◐Partially SupportedGastric banding surgery can reduce food intake by interfering with food grinding, allowing larger particles to pass into the small intestine and trigger satiety signals.