Updated 2nd August 2023

Chronic diarrhea? Here’s what to do

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    We’ve all had unpleasant toilet experiences in our time. It can be distressing to deal with, and it’s not something most of us like talking about. 

    But when does normal diarrhea become chronic? And when do we need to seek medical care? 

    In today’s episode, Jonathan and Dr. Will ask: What is chronic diarrhea, and how can we rule out something more serious?

    Will also shares tricks of the trade to ease your symptoms, and he tells us how our amazing guts work to keep our whole bodies healthy.

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    If you want to uncover the right foods for your body, head to joinzoe.com/podcast and get 10% off your personalized nutrition program.

    Mentioned in today's episode:

    Episode transcripts are available here.

    Is there a nutrition topic you’d like us to explore? Email us at podcast@joinzoe.com, and we’ll do our best to cover it.

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    [00:00:00] Jonathan: Hello, and welcome to ZOE Shorts, the bite-sized podcast where we discuss one topic around science and nutrition. I'm Jonathan Wolf, and today I'm joined by Dr. Will Bulsiewicz. And today's subject is chronic diarrhea.

    [00:00:18] Will: That's right, Jonathan. The rather distressing sounding chronic diarrhea. There's a lot more to this topic than you might think. Above all else, the most important thing is to understand the underlying cause of the diarrhea. 

    [00:00:31] Jonathan: I think we're also gonna discover some more about how our amazing guts work and keep our whole bodies healthy.

    [00:00:38] Will: Definitely, and I, I wanna share a few tricks of the trade to that people can look for if they have symptoms, and sometimes it even involves your sleep patterns. 

    [00:00:48] Jonathan: Interesting. Let's jump into it then.

    [00:00:55] Jonathan: Well, everyone unfortunately knows what diarrhea is. I think we've all had some unpleasant toilet experiences at some point in the past. And we did a podcast on that topic already. But what I want to know, first of all will, is what's the difference between sort of normal diarrhea and what you are describing as chronic diarrhea.

    [00:01:13] Will: Chronic diarrhea, Jonathan is defined as loose or watery stools, which happens three or more times within 24 hours. But the key here is how long it's been going on for. So this is not a one day or one week thing. This is at least four weeks of this type of diarrhea. 

    [00:01:30] Jonathan: Wow. I mean, that sounds really terrible. Are there any other symptoms that people would watch out for if this is happening to them? 

    [00:01:38] Will: Yeah, I hate to say it, but many of us have experienced this you could experience anal irritation when you have this kind of chronic diarrhea. Of course there can be loss of bowel control which leads to incontinence.

    [00:01:49] Will: You could have abdominal discomfort or the urgent need to run to the loo.. 

    [00:01:55] Jonathan: This is all sounds really miserable, presumably chronic diarrhea is something that people should be seeing a doctor about? 

    [00:02:03] Will: So when it's been going on for this period of time, Jonathan, I would definitely recommend that you seek medical care because if left untreated, this could cause dehydration or malnutrition.

    [00:02:13] Will: But the other thing too is that the manifestation of diarrhea could actually be the harbinger of something more serious that's going on with your body. And in that particular setting, you definitely would rather know early in the process so that you can get the treatment that you need. Things can be a little more urgent, but there's certain things that I look for as a gastroenterologist.

    [00:02:31] Will: We sort of call them red flag signs, and these are things like rectal bleeding or progressive abdominal pain, intense abdominal pain, having a fever getting low iron levels. If you don't, if you don't have an explanation for why your iron levels are low. For some people, if you have a family history of inflammatory bowel disease or a family history of colorectal cancer, these would all be reasons to seek medical care earlier in the process.

    [00:02:56] Will: And the other thing too is we have to consider age. So not to be discriminating or anything like that, but as people age, we wanna take these conditions more seriously. So over age 50, we wanna get checked out.

    [00:03:07] Jonathan: So it sounds like in all these situations, it's best to see your doctor if you go and do that, what kind of tests can they do to, to confirm what's going on?

    [00:03:16] Will: So there's a number of different ways that chronic diarrhea can be diagnosed. And in the initial sort of phases of evaluating this, we start with very basic stuff. So the, the medical doctor is gonna wanna take a history, look for certain clues. By the way, we'll talk about some of these clues during the episode.

    [00:03:32] Will: Today, Jonathan they'll wanna do a physical exam and then they may want to do some additional testing, like they could do stool tests, which allow them to check for abnormal bacteria in the digestive system they may want to do blood tests to, to check for things like celiac disease. In some cases, when the answer is not clear based upon the initial testing, then you may move forward with some additional tests, and that could include something like a sigmoidoscopy where the physician will actually be checking your margin test and using a very short, very skinny tube that has a light on it and a camera.

    [00:04:09] Jonathan: I've never heard of this, but I've definitely heard of a colonoscopy. What is the, the difference? 

    [00:04:16] Will: Yeah, so colonoscopy, sigmoidoscopy... they're conceptually similar diagnostic tools . The difference is that with a sigmoidoscopy, first of all, the prep is more straightforward you don't have to completely evacuate your bowels.

    [00:04:31] Will: Second of all, with a sigmoidoscopy you don't necessarily need anesthesia to do this because you're not going very far into the colon. And that's because the key differentiator is how far into the colon you're going. So with the sigmoidoscopy, you see the last half of the colon, the large intestine, whereas with a colonoscopy, the goal is to see the entire colon.

    [00:04:54] Will: And in addition to that, in most cases, when we're trying to figure out what's causing chronic diarrhea, will also be able to use the colonoscope to go into the small intestine and take a look at the very, very last parts of the small intestine, which is important because Crohn's disease can hang out in that specific location. So these are the main things. Now, I've actually had a colonoscopy myself in the United States, colonoscopy is recommended for colon cancer screening. This is a different approach that we take in the US compared to the uk, and that's a debate of its own and there's strengths and weaknesses on both sides.

    [00:05:26] Jonathan: So Will, what are all these tests actually looking for? 

    [00:05:30] Will: Well, this is the thing, Jonathan. There's no global cause for chronic diarrhea. There's a lot of specific diagnoses that your physician has to work through in order to ultimately discover what it is. What is the one that's your particular issue?

    [00:05:46] Will: But what is sort of global or universal when it comes to chronic diarrhea is what's going on inside the body in some regard, which is that water is being either pulled into the intestine or you're not absorbing the water appropriately. And as a result of this, the water is sort of overflowing and causing the diarrhea.

    [00:06:04] Will: And you know, this, this is what sort of brings us to what I consider an essential question. Which has to do with how a person sleeps, right? 

    [00:06:14] Jonathan: So everything made sense until you sort of lost me at the end. Will, why are you suddenly asking about how I sleep? 

    [00:06:20] Will: Actually, this is the critical question from my perspective in terms of understanding what's causing the diarrhea.

    [00:06:26] Will: Cause I can very quickly start to separate things out and understand. And the question is, do you wake up at night to poop? 

    [00:06:35] Jonathan: Right, so this is sort of what you talked a little bit on the previous podcast. So if you have like ibs, irritable bowel syndrome, or something else like that, then actually your gut is just gonna shut down at nighttime in this normal 24 hour rhythm, and you're gonna rest and there's definitely not going to be anything going on.

    [00:06:55] Will: Exactly. So if you are waking up in the middle of the night to have a bowel movement, then there's this whole list of things that includes the most common diagnosis, cerebral bowel syndrome, that you can, I mean, really effectively rule out in that particular setting. It's not likely to be IBS. What it is likely to be, Jonathan is either something infectious or inflammatory.

    [00:07:16] Jonathan: So will, can we start with maybe inflammatory diarrhea? What would typically cause that?

    [00:07:20] Will: When we say inflammatory, we're, we're referring to overactivity of the immune system. And this sort of leads us into specific diagnoses like Crohn's disease and ulcerative colitis, which are forms of inflammatory bowel disease.

    [00:07:36] Will: Another one that people need to know about is microscopic colitis. This is a common condition that causes chronic watery diarrhea. Again, it could wake up in the middle of the night, and it's most classically seen in people as they age, like beyond age 50. Most of the time. Classically in women, all of these conditions that I just mentioned, Crohn's disease, ulcerative colitis, and microscopic colitis, they can be diagnosed with a colonoscopy or in some cases sigmoidoscopy.

    [00:08:04] Will: The one caveat is that microscopic colitis is only seen under the microscope, hence its name. When the gastroenterologist is performing this endoscopic procedure, the colon looks completely normal. So this requires tissue biopsies to make the diagnosis. So if you're going to have one of these tests, sigmoidoscopy or colonoscopy for diarrhea, make sure that your doctor is going to take biopsies during the exam.

    [00:08:36] Jonathan: Thank you. Well, and what about infectious causes? 

    [00:08:41] Will: So these infections, we spoke previously about viruses and things like E-Coli, salmonella, viruses should not be causing chronic diarrhea. And in most cases, in most cases, it's not going to be the sort of classic bacteria like salmonella or E-coli.

    [00:09:01] Will: Usually we think about things like something called clostridioides difficile, which you've probably heard of, and I've mentioned it before as c diff. This usually occurs after people take antibiotics, and this is one of the questions that I always want to know as a gastroenterologist, if you've had chronic diarrhea.

    [00:09:21] Will: My question is, have you had any recent courses of antibiotics? 

    [00:09:26] Jonathan: What would be required if you are sort of worried about this? Is it something that can be diagnosed? 

    [00:09:32] Will: You can get the c diff infection by it being transmitted in the hospital. We take steps in the hospital to really try to protect that sort of transmission from taking place.

    [00:09:41] Will: But you can also get it in the community, Jonathan. And classically it would be after taking an antibiotic. One of the classic antibiotics where people develop c diff infection afterwards is clindamycin so it's just something to be aware of as there's these risks and to answer your question, Jonathan, the way that we would diagnose c diff is with a stool test and you don't have to go to the hospital to get a stool test. You can go to your GP 

    [00:10:03] Jonathan: And if you've got an infectious co cause of diarrhea is it a bad idea to take some sort of anti-diarrhea medicine? 

    [00:10:11] Will: Actually, in most cases, Jonathan, when you have an infection, it's not a good idea to take anti-diarrheal medicine. And the reason why is because your body is actually trying to shed the infection.

    [00:10:22] Will: This is why you're having the diarrhea. And when you take medicines like loperamide, which is available over the counter as Imodium, it actually is going to slow things down and it's gonna start to back you up. And this is potentially dangerous. This is why prior to taking these types of medicines, even when the diarrhea is severe you initially want to get the stool tests done first.

    [00:10:42] Will: That way you can be confident that it's not a bacterial infection that's causing your diarrhea. 

    [00:10:47] Jonathan: So what if people are having this chronic diarrhea, but it's just when they're awake, it's not happening at night. 

    [00:10:55] Will: Yeah. So this is where you can sort of cut things in half very quickly with that question of are you pooping at night? And for the people who are pooping only during the day, this is where we start to think about things more on the spectrum of digestion or absorptive type issues, absorption. 

    [00:11:10] Jonathan: And so will those people generally be having, like the other symptoms we often talk about to do with intolerances, like bloating and all these others.

    [00:11:20] Will: That's exactly right Jonathan. And that kind of diarrhea could be a sign of many different types of absorption related issues. So an example would be celiac disease, or you could have a food intolerance like for example, lactose intolerance, which we've talked about previously on, on this podcast.

    [00:11:36] Will: But there's another one that I should mention here, which is something called exocrine pancreatic insufficiency. We call it EPI for short. And this is a condition that actually is more common than people realize. Tends to occur as we age. And what's happening here is that the pancreas is not able to produce enough enzymes to help us to adequately digest our food.

    [00:11:59] Will: And the issue really tends to occur with fat because that's sort of our area of vulnerability. We, we really need our pancreas to be strong in order to break down and process our fat. So in this particular setting, people who have this issue, they find that fatty foods will trigger diarrhea for them.

    [00:12:15] Jonathan: That's really interesting. I, I'd actually never heard of this so you also mentioned I think bowel syndrome as a potential cause for this daytime diarrhea. 

    [00:12:22] Will: Yeah, and I would say that this is the most common cause of chronic diarrhea but of course, IBS is a diagnosis of exclusion.

    [00:12:29] Will: What that means is that I don't have some sort of specific test that I can do to prove that it's IBS. I have to instead prove that it's not these other things. So if you have these symptoms, you're gonna wanna make sure that it's not celiac disease as an example. So, Some of the signs of IBS that you want to look for include abdominal discomfort.

    [00:12:48] Will: There's always some sort of pain element to IBS. And then in addition to having diarrhea, most people who have IBS will also notice that their discomfort improves after a bowel movement. It's sort of one of the classic signs. 

    [00:13:03] Jonathan: Got it. And we've talked about IBS quite a lot, and I think also some of the ways that, that, that's probably linked with your microbiome.

    [00:13:09] Jonathan: What other questions would you ask your gastroenterologist your doctor, if if this is happening? 

    [00:13:15] Will: Okay, so we, we, we talked about whether or not you're pooping at night. We talked about whether or not you recently had antibiotics, and now the new question that I wanna know is, have you had a cholecystectomy?

    [00:13:28] Jonathan: Okay, you've lost me again, Will. What's that? 

    [00:13:32] Will: So cholecystectomy is the medical term for having your gallbladder removed. And this is of course a rather common surgery that many people have had to remove the gallbladder for a number of different reasons usually gallstones is the classic thing.

    [00:13:47] Will: Now the issue is that a huge percentage of these people, Jonathan, in the weeks or months after their gallbladder is removed, they will have diarrhea. This is pretty common, but the problem is that it can become a chronic issue that's ongoing for a longer period of time. Or in some cases people have had their gallbladder removed, they're fine, and then diarrhea starts later.

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    [00:14:09] Will: In both cases, it can be the gallbladder missing. That's the issue, and the key here is that it's easily treatable. Beyond sort of drilling down on those specific issues. You know, it's really important to also use dietary strategies, and these are things that anyone can, can potentially apply to their life.

    [00:14:28] Will: This includes temporarily cutting out dairy and artificial sweeteners to see if your symptoms get better you could also temporarily remove gluten containing foods, alcohol and caffeine. These are for people who have issues with one of these things, when you for example, routinely consume alcohol or routinely consume coffee, it could exacerbate that problem and actually make it a chronic diarrhea.

    [00:14:57] Will: Also, we should not lose sight of the fact that many medications and supplements can cause diarrhea. And many people, they will take these things and not realize that it's something that you're taking and that's causing it. There's some classics, magnesium non-steroidal anti-inflammatory drugs like ibuprofen or aspirin, vitamin C supplements, metformin for diabetes, and of course the classic — antibiotics.

    [00:15:23] Will: You know, the thing with chronic diarrhea beyond sort of these initial steps is that it's really important to stay hydrated. We talked previously about how water and broth are two great options for this particular thing you could also consider using the BRAT diet. 

    [00:15:39] Jonathan: And Will, I've never heard of this. What is the BRAT diet?

    [00:15:42] Will: BRAT. B-R-A-T. So BRAT is our way of saying bananas, rice, apple sauce, and toast for the short term in terms of trying to improve the symptoms that you're experiencing with your diarrhea. There's not a tremendous downside to trying this this approach. And these are bananas, rice, apple sauce, and toast, as you can imagine.

    [00:16:03] Will: We're talking about things that are sort of starchy and that will help to bind up your stool and give it more form. And one of the big things, Jonathan, is when you're having chronic diarrhea, if you can transition it away from water and towards something more solid, many of the symptoms, including urgency, will improve substantially.

    [00:16:24] Will: And that's one of the, one of the main ways that I've always approached this issue as a medical doctor. You could also consider supplements there's a few that have clear data to be helpful and beneficial in this particular setting. One of them is Saccharomyces boulardii. The dose of this is five grams per day.

    [00:16:41] Will: That's, by the way, is a probiotic. It's a yeast probiotic and it's a yeast that's beneficial and good for us.

    [00:16:47] Jonathan: That's very cool cuz almost always we talk about bacteria. So it's a great example where it's not always a bacteria. 

    [00:16:54] Will: Yeah, it's not always a bacteria. In fact, this probiotic, if you start to dig into the literature surrounding probiotics, there's probably been more studies on this particular probiotic than any. So it's easy to get lost in the shuffle. And the other thing is there's no sort of company that's pumping this because it's not the trendy new thing, but it's the tried and true. And this is one of the settings where it can help. The the other thing too, Jonathan beyond dietary strategies, and of course I'm always a believer diet first.

    [00:17:19] Will: But the other thing too is that prebiotic supplements can help. So when I say prebiotic supplements, I'm specifically referring to fiber supplements, and one of the ones that can really, really help in terms of forming up the stool is partially hydrolyzed guar gum, which we also call P H G G for short.

    [00:17:40] Jonathan: Amazing. Well, Will, that was a great tour around this topic. What's the verdict on chronic diarrhea? 

    [00:17:47] Will: Well, the verdict, Jonathan, is that chronic diarrhea, first of all, let's define what we're talking about. What we're talking about here is three or more stools, looser, watery stools per day that's going on for at least four weeks.

    [00:18:00] Will: And when you're having that particular issue, the biggest question from my perspective is understanding what's going on. What's the actual cause of this issue? Are you pooping at night? Have you taken antibiotics recently? Did you have your gallbladder removed? Those are three of the questions that I would want to know as a gastroenterologist.

    [00:18:17] Will: Beyond this, there's testing. Testing could include stool tests, it could include blood tests or imaging tests, and in some cases invasive testing like sigmoidoscopy or colonoscopy. In some cases, it's absolutely essential in order to get the diagnosis and so don't be fearful or avoidant of those things cuz they can be so beneficial and helpful in terms of understanding it.

    [00:18:37] Will: So that's sort of the process, but let's not lose sight of the fact that there's certain dietary strategies that we could use, specifically a temporary elimination of dairy, artificial sweeteners, caffeine, alcohol, spicy foods, fatty foods, the, these sort of temporary things that you can do while you're getting it all sorted out.

    [00:18:55] Will: Let's think about all those things and try to improve those symptoms while we get to the bottom of this. Amazing. And 

    [00:19:01] Jonathan: I think positive to hear there are things you can do because this obviously sounds like something that is really tough to live with. 

    [00:19:07] Will: Yeah. It's not, it's certainly not fun. It negatively affects quality of life. And a big part of what I have done throughout my career as a gastroenterologist, it's to focus on improving people's quality of life. So, there's so many people out there who are suffering with this and they don't necessarily wanna talk about it openly, but I want them to know that we see them, we know they're out there and we wanna help them and make them better.

    [00:19:26] Will: And so part of it is delivering this information, and part of it is talking to your GP and getting the help that you need. 

    [00:19:33] Jonathan: Thank you. Will. If you'd like to try ZOE's personalized nutrition program to improve your health, you can get 10% off by going to joinzoe.com/podcast. I'm Jonathan Wolf. 

    [00:19:44] Will: And I'm Will Bulsiewicz.

    [00:19:46] Jonathan: Join us next week for another ZOE Podcast.

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