Jan 1, 2026 · 2h 14m
Gastroenterologist Will Bulsiewicz outlines how to repair a damaged gut barrier
Leaky Gut Expert: This Gut Mistake Leads To Cancer. The Cheap Spice That Helps Repair A Damaged Gut!
Understanding the mechanics of gut permeability is essential for preventing chronic inflammation and protecting long-term systemic health.
- 1A compromised gut barrier allows harmful toxins to enter the bloodstream, driving systemic inflammation and chronic disease.
- 2Diversifying dietary fiber and incorporating healing spices can rapidly rebuild and strengthen the gut microbiome.
- 3Prioritizing gut health serves as a powerful preventative measure against long-term metabolic and immune disorders.
Don't miss
Dr. Will Bulsiewicz explains the biological mechanics of leaky gut and how simple dietary spices can help repair the intestinal lining.
The brief
Gastroenterologist Dr. Will Bulsiewicz joins entrepreneur Steven Bartlett to demystify gut health, explaining how the gut microbiome serves as the central operating system for the human body's immune and metabolic functions.
A damaged gut lining, often referred to as leaky gut, allows toxins to enter the bloodstream, triggering systemic inflammation that can ultimately elevate the risk of chronic illnesses and cancer.
Modern lifestyle factors, including highly processed diets and chronic stress, actively degrade our microbial diversity, but targeted dietary adjustments can rapidly initiate the repair of a damaged gut.
Simple, accessible dietary interventions—such as incorporating specific spices and increasing diverse plant fiber—can significantly strengthen the gut barrier and optimize overall physical health.
What was said on this episode
105 statements · 55 positive · 40 negative · 10 neutral
Fecal transplantation rapidly resolved a patient’s severe gut infection.
“By the next day, the entire infectious issue got shut down.”
Listen at 1:23
Constipation is the leading cause of bloating.
“So constipation is the number one cause”
Listen at 2:08
Antibiotics, bottle feeding, and cesarean birth affect microbiomes and increase disease risks.
“antibiotics, bottle feeding and birth by cesarean section are associated with an impact on the microbiome, such as an increased risk of allergic autoimmune and metabolic dise.”
Listen at 2:27
The gut barrier is rebuilt every three to five days.
“every three to five days, you build a new gut barrier”
Listen at 2:40
Optimizing the microbiome through diet and routine improves longevity and reduces disease.
“And when you do these, you will thrive and you will live longer and you will have less disease.”
Listen at 2:48
Following his diet and routine recommendations improves longevity and reduces disease.
“when you do these, you will thrive and you will live longer and you will have less disease.”
Listen at 2:48
Following the book’s advice will transform people’s lives.
“if people take the advice that's in this book and they actually follow it, which is the hardest part, I'm completely convinced it will transform your life.”
Listen at 3:55
Persistent unnecessary immune activation causes health problems and new conditions.
“we're turning on the immune system when we don't need to. And it's staying on 24 hours a day, seven days a week. And that ultimately creates problems because it leads to new issues, new health conditions.”
Listen at 5:05
Chronic inflammation drives fatigue, concentration, sleep, pain, and skin problems.
“Inflammation is driving many of those issues.”
Listen at 6:11
Competitive bodybuilders can have digestive problems despite appearing physically fit.
“these people often suffer with digestive health problems. I know because they reach out to me, including many people that are well known who look incredible and they're suffering with gut issues and then ultimately they're at risk for other health related problems afterwards.”
Listen at 7:03
Gut-barrier epithelial cells turn over every three to five days.
“These cells, they turn over every three to five days.”
Listen at 9:51
Gut-barrier breakdown permits substances to cross through increased intestinal permeability.
“when the gut barrier starts to break down, then things can sneak across, which we would refer to as increased intestinal permeability. But the common language is leaky gut.”
Listen at 10:20
Restoring gut microbes can help repair and restore the gut barrier.
“if you can heal the gut microbes, then the gut microbes can get back to work and do their job of repairing and restoring the gut barrier.”
Listen at 11:14
Neuroinflammation is associated with depression, Alzheimer’s disease, and Parkinson’s disease.
“inflammation in the brain, which we call neuroinflammation, has been associated with mood disorders. So, like major depression, inflammation in the brain has been associated with cognitive disorders like Alzheimer's disease, Parkinson's disease.”
Listen at 13:09
Severe C. difficile infections can be life-threatening.
“those infections, this infection can be life threatening.”
Listen at 15:00
Modern lifestyles damage the gut and gut microbiome.
“the modern world and the way in which we live is damaging our gut, damaging our microbiome.”
Listen at 16:14
The human body produces 3.8 million cells per second.
“Your body produces 3.8 million cells every second.”
Listen at 16:56
Antibiotics before immune checkpoint inhibitors are associated with poorer cancer-treatment outcomes.
“If someone received antibiotics before the immune checkpoint inhibitor, they didn't do well.”
Listen at 18:41
Fecal transplantation before melanoma immunotherapy produced strong treatment results.
“with incredible results.”
Listen at 19:15
Fecal transplantation doubled melanoma cancer response relative to expectations.
“Like, literally twice as many people were beating cancer relative to the expectation.”
Listen at 19:17
Parkinson’s disease may begin in the gut.
“Parkinson's probably starts in the gut”
Listen at 19:45
Constipation can precede Parkinson’s disease.
“they've now shown that the constipation comes before the Parkinson's disease.”
Listen at 20:46
Fecal transplantation produced sustained movement benefits in Parkinson’s patients after one year.
“they had a durable continued benefit in terms of their movement issues.”
Listen at 21:28
People should not perform fecal transplants at home.
“Do not do that. Please do not do that.”
Listen at 22:02
Gas commonly travels alongside stool through the intestines.
“The gas travels with the poop.”
Listen at 28:11
Soluble prebiotic fiber can produce a larger, healthier bowel movement the next day.
“you're gonna have a bigger, healthier bowel movement tomorrow as a result of what I just did.”
Listen at 28:49
Constipation promotes gas and bloating through prolonged microbial fermentation.
“this is a big part of the reason why constipation is so strongly associated with gas and bloating.”
Listen at 29:54
Abnormal intestinal motility can cause diarrhea or constipation.
“If the intestines move too fast and out of rhythm, you get diarrhea. If the intestines slow down too much sluggish, you get constipation.”
Listen at 30:23
Large amounts of unfamiliar fructans can cause gas and bloating.
“if you consume a very large amount of them and you're not used to eating these foods. It can cause gas and bloating these days.”
Listen at 32:32
A gluten-free diet can cause problems without appropriate dietary adaptations.
“it can cause problems to be gluten free unless you know what adaptations to make.”
Listen at 33:37
Glyphosate disrupts the microbiome by reducing beneficial bacteria and favoring inflammatory bacteria.
“We know that glyphosate disrupts the microbiome, that it depletes the beneficial bacteria, and the ones that tolerate it the best are the inflammatory ones.”
Listen at 35:34
Glyphosate disrupts the microbiome, depletes beneficial bacteria, and favors inflammatory bacteria.
“glyphosate disrupts the microbiome, that it depletes the beneficial bacteria, and the ones that tolerate it the best are the inflammatory ones.”
Listen at 35:35
Fermenting wheat dough reduces its fructan content.
“When you ferment your wheat, when you ferment your dough, you actually reduce the fructan content.”
Listen at 36:31
Fermenting bread may improve tolerance among people sensitive to fructans.
“if you ferment the bread, it reduces the fructane content, and actually, then you can tolerate it.”
Listen at 37:12
Fructans, rather than gluten, triggered symptoms in a non-celiac study group.
“the gluten is not the problem, but when they ate the fructan containing bar, they were triggered.”
Listen at 38:21
Many perceived gluten intolerances are actually fructan intolerances.
“we have been taking this concept of gluten intolerance and we've misnamed it. It's not a gluten intolerance, it's a fructan intolerance.”
Listen at 38:34
Many presumed gluten intolerances may actually be fructan intolerance.
“It's not a gluten intolerance, it's a fructan intolerance.”
Listen at 38:39
Inflammatory bowel disease can be placed into deep remission without flares.
“It's possible to put them into remission so deeply that they don't have a flare.”
Listen at 40:02
Children’s microbiomes are approximately adult-sized by age three.
“by three years of age, you are basically fully adult sized in terms of your microbiome.”
Listen at 41:46
A healthy early-childhood microbiome supports a healthier immune system.
“when the microbiome is healthy during childhood, during those first three years, it results in a healthier immune system.”
Listen at 42:03
Ulcerative colitis and Crohn’s disease cases increased up to 55% from 1970 to 2010.
“from 1970 to 2010, ulcerative colitis and Crohn's disease cases were increasing by up to 55%.”
Listen at 43:29
Antibiotic use doubles next-year inflammatory bowel disease risk.
“If you take antibiotics, your risk of developing an inflammatory bowel disease in next year just doubled.”
Listen at 43:49
Antibiotics reduce gut diversity, disrupt the gut barrier, and activate immunity.
“reducing gut diversity, disrupting the gut barrier by 50% during a course of antibiotics and activating the immune system.”
Listen at 44:04
Fecal transplantation rapidly restored a critically ill patient’s condition.
“By the next day, she was a normal human being.”
Listen at 47:38
Restoring the microbiome resolved the patient’s severe C. difficile infection.
“the entire severe infectious issue that she was facing got shut down and corrected by restoring her microbiome.”
Listen at 47:52
An all-meat or organ-only diet is not optimal for longevity.
“I don't believe that a 100% meat or organ only diet is in balance or the optimal solution for longevity.”
Listen at 50:42
A fruit-only diet should not be recommended.
“a fruit only diet, I would never support or recommend either. That's completely insane.”
Listen at 50:54
Removing irritating foods can temporarily improve gut symptoms.
“you will often feel better if you have gut issues and you take away the stuff that's irritating your gut.”
Listen at 51:20
Dietary choices can alter the microbiome by the following day.
“the choices that you make today will be reflected in your microbiome by tomorrow.”
Listen at 51:47
People should increase fiber gradually rather than abruptly.
“you have to ease your body into it.”
Listen at 53:28
Most Americans and Britons consume insufficient fiber.
“95% of people in the United States and 90% of people in the UK are deficient in fiber”
Listen at 53:52
Fiber feeds beneficial bacteria and enables short-chain fatty-acid production.
“Fiber is the principal food for the good bacteria and it is the precursor to short chain fatty acids.”
Listen at 54:06
Short-chain fatty acids are highly anti-inflammatory.
“these are the most anti inflammatory thing that I've ever come across.”
Listen at 54:35
Fruits, vegetables, whole grains, seeds, nuts, and legumes contain fiber.
“Fruits, vegetables, whole grains, seeds, nuts and legumes, they all have fiber.”
Listen at 57:03
Butyrate is needed to produce proteins that maintain the gut lining.
“you literally need butyrate in order to produce the proteins that hold your gut lining together.”
Listen at 58:53
Hunter-gatherer lifestyles protected tribal populations against age-related inflammation.
“they were protected against inflammation regardless of their age, because of their lifestyle.”
Listen at 1:00:40
Alcohol-related gut-barrier disruption activates inflammation.
“So, and this is where inflammation comes from.”
Listen at 1:02:45
No amount of alcohol is safe according to his interpretation of the evidence.
“I don't think there's any amount of alcohol that's safe”
Listen at 1:03:50
Any detectable blood alcohol level can cause leaky gut.
“any amount of alcohol that's detectable in the bloodstream can.”
Listen at 1:04:39
Gut destruction is a necessary step toward alcohol-related cirrhosis and liver disease.
“that's actually a requisite step on the pathway towards developing cirrhosis and alcoholic liver disease.”
Listen at 1:04:55
Turmeric may reduce inflammation by blocking a cytokine.
“Turmeric is helping inflammation to go down because it blocks another one of the cytokines.”
Listen at 1:09:10
Curcumin, the active turmeric compound, is a polyphenol.
“curcumin is what we call a polyphenol.”
Listen at 1:09:41
Curcumin and colorful plant-food polyphenols affect the gut.
“curcumin is what we call a polyphenol. So polyphenols, as we sit here and we look at this beautiful array of all of these colors, every single one of these foods contains polyphenols that define the color and that impact the gut.”
Listen at 1:09:41
Excessive turmeric supplementation can cause problems.
“if you overdo it, if you take too much, that could create an issue”
Listen at 1:10:22
He recommends beginning the day with quiet reflection before other activities.
“what I want you to do in the first five minutes of your day is I want you to initially just focus on waking up and thinking about your day”
Listen at 1:12:03
He recommends morning water with a prebiotic fiber supplement.
“we're going to opt for water. And in a perfect world, I would love to add a prebiotic fiber supplement to that water.”
Listen at 1:12:27
Morning sunlight or bright light is a primary circadian-rhythm lever.
“Number one, sunlight. Or at a minimum, bright light exposure.”
Listen at 1:13:34
Morning light exposure can increase the cortisol peak by 50%.
“by getting morning light exposure, you can bump it by 50%.”
Listen at 1:15:23
Light morning exercise can support circadian activation.
“if you just move your body, right, which during the summertime, what you would do is like, you might go outside and you might have a ruckfest and you take a walk”
Listen at 1:15:44
Eating earlier improves blood sugar and blood-fat control.
“when you eat it at 7:45, you will get better blood sugar control. You will get better blood fat control.”
Listen at 1:19:15
He recommends high-fiber, moderate-protein, low-sugar breakfasts.
“I would argue that we go high fiber and moderate protein, low sugar, no sugar.”
Listen at 1:19:37
He recommends organic, minimally processed oats.
“The oats should be organic, and if you were to do them, do them as minimally processed.”
Listen at 1:20:36
Higher maternal fiber intake during pregnancy may reduce children’s later allergy risk.
“moms who increase their fiber intake during pregnancy reduce the likelihood of their kids developing allergic diseases later on as well.”
Listen at 1:22:37
Human milk oligosaccharides feed the developing infant microbiome.
“Human milk oligosaccharides in breast milk were basically designed to feed the developing baby microbiome.”
Listen at 1:24:05
Early antibiotic exposure and bottle feeding predict later allergic disease.
“exposure to antibiotics in the first year of life, number two, being bottle fed.”
Listen at 1:25:18
Infant microbiome patterns can predict later allergic disease.
“you can look at the microbiome and predict who will later on go on to develop the confused immune system with these allergic diseases.”
Listen at 1:26:16
He recommends vitamin D, omega-3s, and turmeric as morning supplements.
“the morning supplements, the ones that I recommend that are evidence based are vitamin D, omega 3s and turmeric.”
Listen at 1:26:44
Supplements are most useful when testing shows a deficiency.
“If you have enough, you don't need to take the supplement. But if you're deficient, that's where supplements play an important role.”
Listen at 1:27:04
Morning light exposure contributes to a healthy bowel movement.
“when you get your morning light exposure, that helps to contribute to that bowel movement.”
Listen at 1:27:51
Loneliness has health and longevity impacts comparable to routine cigarette smoking.
“Loneliness has been shown to be on par with smoking cigarettes on a routine basis in terms of the impact that it has on your health and your longevity.”
Listen at 1:29:09
A ten-minute walk can improve blood-sugar control by 30–40%.
“a 10 minute walk, just 10 minutes of simple walking, is enough to get 30 to 40% improvement in your blood sugar control.”
Listen at 1:33:15
A post-meal outdoor walk can reduce bloating and support gut rhythm.
“the outdoor walk also activates our gut and helps our gut to get into rhythm and that reduces bloating after a meal.”
Listen at 1:33:46
Matcha has the highest polyphenol content among teas and benefits the microbiome.
“this is, of all the teas that exist, that has the highest polyphenol content and it's phenomenal for the microbiome”
Listen at 1:34:06
Spacing meals approximately four hours apart supports digestive rhythm.
“We've spaced things out by about four hours and that's actually the perfect time from the perspective of your digestive rhythm.”
Listen at 1:36:12
Four-hour meal spacing improves digestion by supporting gut rhythm.
“it's ideal to give a four hour space between these meals and that if you do that, you will actually notice a difference in terms of how you feel with your digestion.”
Listen at 1:36:45
Evening household light can reduce melatonin by 30%.
“casual lights within your home can cut your melatonin down by 30%.”
Listen at 1:37:29
A cool, dark bedroom improves sleep.
“we want a cool room, we want a dark room and that will help us to sleep better”
Listen at 1:40:03
Consistent sleep timing is more important than a specific bedtime.
“Consistency is key.”
Listen at 1:40:26
Late-night eating worsens metabolism and sleep.
“when you eat late at night, it hits you different metabolically and then it carries and it lingers into the next day and it will affect your sleep.”
Listen at 1:41:18
Time-restricted eating longer than twelve hours benefits the gut.
“anything over 12 hours is good for the gut.”
Listen at 1:42:01
Chronic sympathetic activation harms gut function.
“We live our lives on sympathetic overdrive, which basically is the equivalent of constantly feeling threatened, right? Heart rate, heart rate pumping, blood pressure up, more focused, but then you suffer the consequences within your gut. The gut gets sacrificed.”
Listen at 1:45:40
Trauma can leave the amygdala persistently activated.
“people that suffer from trauma is that they live with the amygdala perpetually turned on.”
Listen at 1:47:44
Persistently elevated cortisol disrupts the gut barrier and causes inflammation.
“the cortisol then disrupts their gut barrier and leads to inflammation.”
Listen at 1:50:35
Trauma-related gut problems should be addressed with professional help.
“the solution is to accept and acknowledge that the trauma is the root of the problem. Because then you need to actually turn towards it. And that's under professional. That's with professional help.”
Listen at 1:51:23
Trauma-related gut problems should be addressed with professional help such as cognitive behavioral therapy.
“that's under professional. That's with professional help. So there's different things that you can do, different approaches, including cognitive behavioral therapy.”
Listen at 1:51:31
Bristol stool type four represents a normal bowel movement.
“the Bristol 4 is the normal bowel movement”
Listen at 1:52:50
Bristol stool types one and two indicate constipation; six and seven indicate diarrhea.
“type one and two are constipation and types six and seven are diarrhea.”
Listen at 1:53:33
Magnesium supplementation can complement fiber for severe constipation.
“sometimes you have to add magnesium. Magnesium supplements are great with fiber.”
Listen at 1:54:59
Magnesium oxide is his preferred magnesium form for constipation.
“For constipation, magnesium oxide is the one that I would typically go with”
Listen at 1:55:36
Diarrhea can result from overflow in people with chronic constipation.
“there are some people who suffer from chronic constipation and then they start having diarrhea and actually that's overflow.”
Listen at 1:56:02
The most effective dietary pattern is the one a person can sustain.
“The one that's going to work the best for you is the one that you're actually willing to do.”
Listen at 1:56:43
Healthy dietary patterns share fiber, polyphenols, healthy fats, and fermented foods.
“I've identified four things, and these four things you find in all of the healthy dietary patterns.”
Listen at 1:57:07
Oil is extremely calorie-dense and should be limited during weight loss.
“if you are obese and you're trying to lose weight. The problem with any oil, not just seed oils, also including extra virgin olive oil, is that this is the highest calorie thing that exists on the entire planet.”
Listen at 1:57:48
Adding fermented foods for eight weeks increased microbiome diversity and lowered inflammation.
“in just eight weeks, by adding fermented food to their diet, people could increase the diversity of their gut microbiome. That means a healthier gut, and they lowered inflammation.”
Listen at 1:59:08
Changing diet, lifestyle, and exercise contributed to his physical transformation.
“I changed my diet. I changed my lifestyle. I grew up eating junk food. I grew up eating fast food. We celebrated that sort of diet. And I shifted towards eating the way that I'm describing to you today. I obviously started going to the gym and working out.”
Listen at 2:00:39
Statements are attributed to the speaker as said on the episode and reflect their view at the time, not PodLume's. They are not advice.
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