The Ultimate Guide To Overcoming IBS! – with Dr. Mark Pimentel

Are you one of the millions of people around the world who struggles with IBS (Irritable Bowel Syndrome)? IBS is one of the most common chronic disorders globally, but despite being so common, IBS is often misunderstood. That’s why, in today’s episode, we are explaining IBS, the potential causes of IBS, SIBO, stress, how diet can help or hurt with IBS, and more with Dr. Mark Pimentel! 


We answer these questions:

– What is IBS?

– What are some of the top causes for IBS?

– What symptoms could indicate IBS?

– How does SIBO relate to IBS?

– Why do women seem to be more affected than men by IBS?

– Does stress affect IBS?

– What sorts of foods make IBS worse?

– And more!

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About Dr. Pimentel:

Mark Pimentel, MD, is currently the head of the Pimentel Laboratory and executive director of the Medically Associated Science and Technology (MAST) Program at Cedars-Sinai. This program focuses on the development of drugs, diagnostic tests and devices related to conditions of the microbiome.

The Pimentel Lab researches irritable bowel syndrome (IBS), one of the most prevalent gastrointestinal (GI) conditions effecting about 10 percent of the population worldwide and about 10 to 15 percent of people in the U.S. In the past, there was no definitive test to diagnose IBS. For a time, IBS was thought to be a psychological disease; however, the Pimentel Lab discovered a blood test to provide a definitive diagnosis showing that IBS is an organic disease. Having a definitive diagnosis for IBS paved the way for additional research in the Pimentel Lab to treat the condition. 

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Dr. Ann-Marie Barter is a Functional Medicine and Chiropractic Doctor at Alternative Family Medicine & Chiropractic. She is the clinic founder of Alternative Family Medicine & Chiropractic that has two offices: one in Longmont and one in Denver. They treat an array of health conditions overlooked or under-treated by conventional medicine, called the “grey zone”.



Dr. Mark Pimentel [00:00:00] What we do say and what we do know very clearly is stress makes people’s gut uncomfortable. If you’re an acute, really bad stress, you might feel awkward or butterflies or problems with your stomach. But stress is not the cause, not the culprit of IBS.

Intro [00:00:18] Are you struggling with bloating, gas constipation and fatigue, but don’t know what’s causing these problems? The Gut Health Reset podcast with Dr. Ann-Marie Barter dives deep into the root causes behind these issues that start in the gut. This podcast will give you the knowledge you need to heal your gut and reset your health.

Dr. Ann Marie Barter [00:00:39] Today on the Health Reset podcast, we are discussing the origin of that painful bloating or that diagnosis of IBS. Did you know that it could have started one unfortunate night after a food truck experience or after food poisoning? We’re going to drill down to figure out what tests you can run, what treatments are on the horizon for IBS? And today my special guest is Mark Pimentel. And he is an M.D. who is currently the head of the Pimentel Laboratory and executive director of the medically associated science and Technology Program at Cedars-Sinai. This program focuses on the development of drugs, diagnostic tests and devices related to conditions of the microbiome. The Pimentel Lab researches irritable bowel syndrome IBS. One of the most prevalent gastrointestinal conditions affecting about 10 percent of the population worldwide and about 10 to 15 percent of the people in the U.S.. In the past, there was no definitive test to diagnose IBS for a time. IBS was thought to be a psychological disease. However, he has discovered a blood test to provide a definitive diagnosis, showing that IBS is an organic disease. Having a definitive diagnosis for IBS paved the way for additional research in the Pimentel lab to treat their condition. Mark, it is such a pleasure to have you on the podcast. I’m really grateful to have you here today, and I know you are doing amazing work in the IBS field, and that’s why I really want it to have you on the podcast today because there’s a lot of myths around IBS, so let’s just dove right into it. So what is IBS?

Dr. Mark Pimentel [00:02:41] Well, irritable bowel is like you for having me on the show. Regular bowel syndrome is a condition that’s chronic. You have chronic abdominal pain and changes in bowel function and a lot of bloating, gas and distension. But if I can put a plug in right away the term irritable and bowel and that you’re a syndrome and not a disease, that’s the term very frustrating for patients because it’s a really derogatory set of words that we label our patients as irritable.

Dr. Ann Marie Barter [00:03:12] Mm hmm. It’s a good way to put it, and it seems to be a trash can diagnosis that once all the tests are ruled negative for, say, more inflammatory bowel conditions. Well, you have IBS. And so what do you think some of the causes are of folks having this condition because it’s fairly it’s not uncommon.

Dr. Mark Pimentel [00:03:41] Right? I mean, it affects 10 to 15 percent of the population. And if you take that worldwide, it’s about a billion people. We’re not talking about a small disorder. And so it’s shocking that you would treat such a massive amount of patients with this kind of trashcan diagnosis, as you put it. And yes, the original description of IBS as a definition used this word diagnosis of exclusion or trash can diagnosis. And to be honest, that definition in and of itself has made IBS so expensive and so difficult for patients because it puts the obligation on the doctor. Hey, you’ve got to do a colonoscopy, you’ve got to do this, you’ve got to make sure it’s not something else. And then, you know, we’ll call it IBS at that point. And that’s the trashcan analogy that you used. But things are different now. I mean, it’s not what it once was, but I’ll tell you that patients are still frustrated because there are doctors out there who still say, Well, it’s a women’s disease, it’s because of their anxiety. I even had a doctor. An older gentleman who was teaching fellows say IBS is a diagnosis of hysterical women, which is a shame in 2018. Are you kidding me? I mean, that’s a shame. But but you see, this is this is the problem. But we know now in the last decade, we know a ton about what causes IBS. And I know we’re going to get into it. But food poisoning is the start. That’s the thing that starts the whole process, and we know a lot about that process now.

Dr. Ann Marie Barter [00:05:12] So let’s go into that. Like what is, you know, where this is cause or where the causation is from four IBS. So you start you said it starts with food poisoning and let’s kind of drill down from there.

Dr. Mark Pimentel [00:05:24] Yeah. Well, you know, one of the things we’ve known for a little while is that food poisoning seems to trip off the gut in this way. But but in the last decade, and it’s really a ton of work by a lot of people and we’ve been blessed to be part of that group, those groups. But we now know in 2021 that food poisoning and a particular toxin called See DTB sets up antibodies and those antibodies then react with you, a protein called binocular. And then the nerves of the gut get affected by that antibody. That doesn’t flow correctly. The gut builds up bacteria, and then you get all these crazy symptoms the pain, the bloating, the the the diarrhea. And that also sets up an opportunity to understand better treatments, which we’ve really come a long way with.

Dr. Ann Marie Barter [00:06:12] Mm hmm. And so this test to check for this, this isn’t commonly checked for why is that?

Dr. Mark Pimentel [00:06:22] Well, so like anything in medicine, it takes about 10 years for it to filter down to the primary care level when most of the IBS is seen. It just requires education. But this test, which measures anti-wrinkle in an anti KDB if they’re positive, you’re post-test probability of having IBS is 98 percent. So you can walk away from a doctor, visit two days later and say, OK, I’ve got IBS. The test is positive and you know why it’s food poisoning. But think about that compared to what we were doing before. Studies have shown that patients feel confident with their diagnosis of IBS. It can take up to six years because they go to one doctor. Doctor says, Well, everything’s negative. I think you have IBS. Well, the patients like that. How do you know? You know, everything’s negative. You’re just guessing. Right. And and so then they go to another doctor or they try to put up with it for a while. So we can, you know, get an answer now in 48 to 72 hours. And then you stop, pause and start treatment, which saves money and hassle for the patient.

Dr. Ann Marie Barter [00:07:23] Mm hmm. And so what symptoms? I know that bloating, discomfort, constipation or starting this cascade? What other symptoms could? Could somebody present with with IBS?

Dr. Mark Pimentel [00:07:39] Well, bloating is the big one. You know, you wake up in the morning, your abdomen looks flat, feels flat, it’s OK. And then you start to eat the bacteria of the gut or making gas and you really get distended and bloated and you feel uncomfortable. One of the big symptoms that a lot of the patients with diarrhea have is the diarrhea of IBS, unlike other diseases, is unpredictable. So you wake up in the morning, you have nothing and you go to work, you have nothing, and then you’re in the middle of a meeting with your boss and you got to run and you’re gone for half an hour because it just takes that long for the diarrhea to settle. Or you’re just about to get on an airplane and you buckle in your seat, and all of a sudden you need to go in there saying, Well, you can’t take your seatbelt off. I mean, it drives you crazy that it just sort of pops in intermittently or unpredictably. And I think that that part of the the symptoms, the unpredictable nature really is a suffering point for these patients.

Dr. Ann Marie Barter [00:08:33] When you talk about kind of the bloating piece of it, you know, you wake up your abdominal region is flat and then throughout the day you tend to get more distended. That sounds a whole lot like CBO. How does CBO play into this picture, right?

Dr. Mark Pimentel [00:08:52] Well, she was a very in the last two years, CBO and IBS have become very much intertwined. And all of the review articles are starting to put them all together. But but let me talk a little bit about CBO and then weave it into IBS. But CBO can be caused by anything that causes the gut to slow down. So think of think of your pipe or drainpipe in the sink in your kitchen. If it’s flowing, well, nothing is, you know, it’s not dirty, it’s not sewage. But if the drain starts to plug up, you get this dirty material that builds up in the gut is like a plumbing system as well as of the small bowel doesn’t clean itself properly and doesn’t flow correctly. The bacteria will love that food and grow and proliferate. And then when it does, it’s getting fresh food and it produces gas. And so that’s Zebo. And in IBS, we now know from all the clinical trials that have been done that about 60 or more percent of IBS with diarrhea, they have Zebo. And now we know that the bacteria that cause constipation are not bacteria at all. They’re methanogens and they produce methane. So we’ve got sort of in 2021, we now know methane is causing the constipation side from the methanogenic organisms. We know cibo and particular hydrogen sulfide. The new kid on the block is causing the diarrhea side, so all the pieces are starting to come together. It starts with food poisoning. You get this slowing of the gut. And depending upon what bacteria build up, you get these different outcomes in terms of your symptoms.

Dr. Ann Marie Barter [00:10:35] And this is what makes I mean, because you’ll see different cibo cases. And I know sometimes there’s there’s multiple ways you can treat Zebo write. The literature has been, you know, antibiotics will work. Certain herbal concoctions will work for Cipro, but CBO keeps coming back when CBO keeps coming back with these treatments. What does that say to you?

Dr. Mark Pimentel [00:10:59] Well, so that’s why the antibiotics are so important because the anti insulin antibody is causing the gut not to flow correctly. That’s what we’ve seen in our animal studies and in the humans. The higher that is, the worse off you are. So knowing that gives you some prediction of how tough it’s going to be for you, how easy it is to get rid of it. But remember, you can get rid of the bacteria with an antibiotic or an herbal cocktail, but you can’t make the motility or the movement of the gut come back because that antibodies are still there. And right now in 2021, we don’t have a drug to get rid of that antibody, although, you know people are working on it or trying to figure it out. So you have to use something to make the gut move better. We often use pro genetics after, you know, so we treat with an antibiotic. They get better. You put them on the patient, on a pro kenetic to keep the gut moving better. So that is sort of like you’re continuously flushing the drain of your sink so that this doesn’t build up again. And that’s what the motility drug does, rather than replacing the drain. You’re kind of making the flow better.

Dr. Ann Marie Barter [00:12:05] Yeah. Good analogy there. Good analogy. So you said that you don’t really have a treatment for the antibody yet, so there’s not really a treatment at this point. Is that correct?

Dr. Mark Pimentel [00:12:20] That’s correct. But that doesn’t mean that the antibody isn’t so lots of times. Doctors want to do a test in the metal, tell them how to treat patients. But I can tell you when the antibody positive, I know how bad it’s going to be for them. But the other thing is, it also puts them at risk for food poisoning again. So if you know that you have these antibodies, you got to be more cautious than anybody else. When you travel, when you eat, where you eat, how you eat. Maybe a food trucks aren’t the right thing for you because you never know. And because those antibodies can go higher and higher with each and each food poisoning. So we do this routinely in our patients.

Dr. Ann Marie Barter [00:12:57] So many people struggle with bloating, bowel issues, brain fog, fatigue. You might not even have any gut issues, but did you know the cause of it could be food sensitivities or gut infections? What I have? On as I have brought a talented functional nutritionist into my practice, we have very similar training in the nutritional world. And her name is Alexis Appleby. She is awesome. So you can head on over to our website. &Lt. Alti Fam Fam Med Med and have a consultation with her and schedule so that she can help you get to the root cause of your problems. OK? And it does it really just take one food poisoning incident to start this cascade?

Dr. Mark Pimentel [00:13:47] Yes. And the risk factors are you can just have one food poisoning and then suddenly, if it’s bad enough, you’ll have IBS for the rest of your life. I mean, that’s how it can sometimes be. And it also depends on the type of food poisoning and how aggressive it is. So the worse you’re food poisoning is if you have a week of diarrhea, you end up in the hospital. You’re more likely to get IBS than somebody who just has a couple of bowel movements that are runny and then everything goes away. So that’s that’s a really important factor. But but I will say one more thing because women, more women have IBS. But if a woman gets food poisoning, they’re almost twice as likely to develop IBS. And that is that might be the reason why more women have IBS, not the other explanations I gave you earlier that are silly.

Dr. Ann Marie Barter [00:14:35] Mm-Hmm. Yeah, that that’s I think my main question is why are women so much more affected than men in this cascade?

Dr. Mark Pimentel [00:14:45] Well, we don’t have the answer to that, but I will say that we’re starting to think that IBS is an autoimmune disease because of this autoantibodies that we’re finding and more women tend to get autoimmune diseases more than men, rheumatoid arthritis, lupus, those types of illnesses. It doesn’t explain why women are susceptible to autoimmune disease, but I’m just the pieces are starting to set in. That women’s immune system are different and they react differently. For reasons we don’t completely understand. But yes, that happens.

Dr. Ann Marie Barter [00:15:16] You brought up, I think, a great point at the beginning when when a colleague of yours was talking about how women, it tends to be basically an emotional mood disorder that women tend to have. Now we do know that the literature has linked stress to IBS. What’s your feeling on how much that plays a role?

Dr. Mark Pimentel [00:15:39] Well, let me start by saying there is absolutely no randomized controlled trial where they take a thousand people and they randomized half distress and half to no stress to see if IBS develops. Never been done. And so what we do say and what we do know very clearly is stress makes people’s gut uncomfortable. If you’re an acute, really bad stress, you might feel awkward or butterflies or problems with your stomach. But stress is not the cause, not the culprit of IBS. The further along we go year by year, the less likely we’re seeing that as the primary cause. The primary causes food poisoning in most cases. But I’m not minimizing stress, anxiety, depression, historical stressful events and people’s lives. Those things are, of course, important and affecting their psyche. But we’re not saying that’s the cause of their IBS anymore, or we shouldn’t be.

Dr. Ann Marie Barter [00:16:41] Mm-Hmm. Do you think that anything else is contributing to the symptoms of IBS besides food poisoning and cibo? And also, I guess, slow motility?

Dr. Mark Pimentel [00:16:55] Well, there are other theories for some of the remaining patients. So for example, if we think 60 percent of IBS is cibo, there are some people who suggest bile acids may be important. There are others who suggest maybe inflammation or mast cell conditions may be important in another subset. So I guess what I’m stacking together is at the end of the day, in another 10 years when the science tells the truth of what’s going on, the 100 patients of IBS that we started with today, 60, maybe this 10, maybe this five, maybe this and we’re breaking it down and trying to figure it all out. But maybe a good segue way as diet plays an important role in some of the symptoms these patients have. So once you have IBS and Zebo, diet can really affect you in a negative way. And and one of the things I don’t want to keep going down this tangent, but one of the things that patients drive, what also drives patients nuts is they say, you know, I had pasta last night, two three nights ago, I have no problem. Then I had pasta last night, the same restaurant and I had bad diarrhea, and they say it must have been the pasta, but doesn’t make sense. Well, the problem is everybody when they think of. Area, they think of the last thing they ate. But it could have been three days ago or two days ago what they ate. The bacteria levels are going up and up and up from that, and then all of a sudden they eat the pasta they’ve eaten didn’t bother them three days ago. Now it’s bothering them. So it’s really hard for patients to sort out the diet. So that’s where we come in to try to help them.

Dr. Ann Marie Barter [00:18:32] What triggers have you seen with IBS and diet?

Dr. Mark Pimentel [00:18:36] Well, absolutely. Anything that causes excessive ferment tation is going to make this much worse for patients. So beans and legumes are essentially off the list. I mean, you just can’t eat those because you will be uncomfortable. They tend to be lactose intolerant because of the bacteria that are in there. Most humans require the whole small bowel to digest lactose. Even people who can drink milk very well. And if you spread that lactose across bacteria, they’re going to, they’re going to eat it faster than you can and produce gas. So a lot of lactose intolerance in that population. And then what’s amazing in the food industry is all the diet drinks or diet foods have sucralose now as their their sweetener and sucralose is like drinking a sugar that you can’t absorb. Guess who gets it if you don’t get it? All the bacteria and you just blow like crazy and you don’t even realize it because some food items. Three weeks ago, they had aspartame, which is fine, because it’s a protein. And then now it’s sucralose, and you didn’t even know they change the ingredients. And then all of a sudden your bloating. So yeah, those are the big culprits, though.

Dr. Ann Marie Barter [00:19:49] And where have you seen the most relief? What have you done to see the most relief with IBS? At this point, it sounds like changing diet and also treating the cibo infection, as well as trying to move the bowels. Has that been where you’ve seen the most relief?

Dr. Mark Pimentel [00:20:08] Yeah, I think getting rid of the CBO is the key because if you can do that, those are the patients that experience the best benefit. We’ve published a paper on that that shows if you want to make IBS better, your best outcome will be if you can get rid of the bacteria. What we’re doing in our research right now in what’s called a reimagined study, we’ve actually found out who the bacteria are that are part of the Zebo IBS and where they live, because where they live, they’re hiding from the antibiotics and the mucus and in other parts of the gut. So now that we know where they live, we’re going to have better treatments in the very near future that we think will be even better than what we currently do.

Dr. Ann Marie Barter [00:20:48] So I have seen that a lot of maybe folks aren’t on board with testing for Cibo. Why is that?

Dr. Mark Pimentel [00:20:59] Well, you know, some doctors, it’s hard to change. They have their pattern of practice. Other doctors don’t like IBS patients because they’re quote, difficult and hard to get them better. But that also is changing because now the new therapies work quite well, much better than they used to. And and doctors actually are getting some good responses. Unlike previously, but one of the thing about breath testing is that it was always incomplete. We had hydrogen on the breath test. We had methane on the breath test, but we needed to have the third gas hydrogen sulfide, and that’s the new kid on the block because hydrogen doesn’t correlate with symptoms. If it’s positive, yes, you have cibo. But if you had 104 hydrogen, it’s not any worse symptomatically for the patient than it was 40, which is, of course, a lot lower because methane is what’s causing the constipation and hydrogen sulfide is causing the diarrhea. And now that we measure all three gases, that’s that’s the ticket that’s going to help doctors get a better connection to therapy. And what gas you see on the breath test will tell you what therapy is off the.

Dr. Ann Marie Barter [00:22:07] And I think one of the the main questions I get is how do I approach my physician where I know that I have all these symptoms? I listened to your podcasts and have all these symptoms and my physician won’t run a cibo test or won’t look into these things. So how can a person approach their doctor to get some of this testing and treatment done?

Dr. Mark Pimentel [00:22:34] Yeah, I mean, that’s still a challenge. And some of what we call the white spaces places that are in in either rural areas or areas where there isn’t academic medicine as much. And we try to do our best through podcasts like this to get to these patients and give them information or their doctors hopefully will listen to them. But I know what’s out. I don’t have an easy answer for it. Get another doctor, somebody who will listen. There are groups and community groups that are very helpful in providing names of doctors in various areas of the country that can, you know, that are more amenable to understanding this or are up to date because this is this is stuff that’s published in the New England Journal of Medicine. This isn’t fringe science. This is this is contemporary science that their doctor doesn’t read it. It’s really the doctor’s obligation to keep up with what’s going on. Mm-Hmm.

Dr. Ann Marie Barter [00:23:33] Yeah. Well said. Well said. Did we miss anything about really drilling down on IBS that really should be addressed?

Dr. Mark Pimentel [00:23:43] Well, I think what I like to do with talking to theater patients or doctors is that we now know more about the cause of IBS than we do. Crohn’s are all sort of colitis that has flipped in the last 10 years, and we’ve talked a lot about it. But the point of that is imagine how things have changed because IBD was sort of the darling of many different drugs getting approved. But now it’s IBS and we actually know more. And so I think patients should have a strong level of optimism that we’re on it and many others are as well, and that we’re coming up with new ideas, new treatments that will be much better than we currently have just in the next couple of years. So hang tight, try and find a doctor who knows the science and we’ll have more stuff to come.

Dr. Ann Marie Barter [00:24:37] Well, thank you so much for sharing your knowledge. Thank you so much for sharing the cutting edge research that’s being done here. And I think that a lot of folks will benefit from the podcast and hopefully, you know, it’ll change the way that IBS is being treated.

Dr. Mark Pimentel [00:24:53] I really hope so, and it’s been a pleasure to talk to you today. Thank you so much.

Outro [00:24:57] Thank you. Thank you for listening to the Gut Health Reset podcast. Please make sure you subscribe, leave a rating and a review. More people can hear about the podcast and hey, take a screenshot of this episode and tagged Dr. Ann Marie on Instagram or Facebook at Dr. Ann Marie Barter. And for more resources, just visit Dr. Ann Marie 


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