#15a: Eat for IBD with Dr Alan Desmond (part 1 of 2)

4th Feb 2019

In this episode, we talk about eating for about Inflammatory Bowel Disease (IBD) or Colitis. We talk through exactly what IBD is - but the podcast really covers gut health in general.

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Today I talk to the incredible Dr Alan Desmond who is a Gastroenterologist based in Devon.  He has some really interesting views on how we can utilise diet and lifestyle to improve not only our gut health but also Type 2 Diabetes, Cholesterol and Cardiovascular diseases - all other features that are really important in today’s healthcare landscape.

In these episodes, we cover:

  • Inflammatory Bowel Disease (IBD)
  • Ulcerative Colitis
  • Crohn's Disease
  • Colon Cancer
  • Just how influential lifestyle and diet can be on gut health and associated conditions
  • How beneficial a plant focused lifestyle, including increasing your fibre intake and getting more colours onto your plate, can be for inflammatory conditions such as IBD

Episode guests

Dr Alan Desmond

Dr Alan Desmond, MB BCh, BMedSc, MRCPI, FRCP Dr Alan Desmond is a Consultant Gastroenterologist based in Devon. Board Certified in both Gastroenterology and General Internal Medicine, he completed his specialist training in Cork, Dublin and Oxford.

Dr Desmond is his hospital’s Clinical Lead for the treatment of Inflammatory Bowel Disease, a topic on which he has published numerous research papers. Dr Desmond actively promotes a Whole Food Plant-Based Diet, particularly for patients with chronic digestive disorders.

He is a founding Advisory Board member of Plant Based Professionals UK and is currently engaged in Clinical Research evaluating a Whole Food Plant-based Dietary Intervention as a treatment for patients with Crohn’s disease.

You might find Dr Desmond’s talk on YouTube interesting. It covers the evidence for the role of diet in IBD. The topics discussed are highly relevant to Crohn’s disease in particular, but also have relevance to ulcerative colitis and many other GI disorders. Youll also have heard Alan talk about The Happy Gut Course that he is running with The Happy Pear. 

There are also two scientific reviews of the role of diet in IBD in a paper written for the BMJ and another for the Oxford Academic Journal. During the podcast, we also cover a second paper covering IBD for the Oxford Academic Journal and have attached a copy of the diet referenced here.

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Podcast transcript

Dr Alan Desmond: We live in a country here in the UK where 55% of calories come from ultra-processed foods, which don't have any phytonutrients or fibre in them, where the average bacon consumption is 5 kilos per person per year, where the majority of people aren't getting anywhere near the recommended daily intake of fibre of 30 grams a day. It's more like 14 or 15 grams a day.

Dr Rupy: Today we're going to be talking about eating for inflammatory bowel disease or colitis. We're going to talk about exactly what that is, but it's really going to be a general podcast about eating for gut health. And I'm going to be joined by the incredible Dr Alan Desmond, who is a gastroenterologist who's based in Devon. He has some really interesting views on how we can utilise diet and lifestyle to improve not only our gut health, but also type two diabetes, cholesterol, cardiovascular disease and all other features that are really important in today's healthcare landscape. Don't forget my first book, the best-selling Doctor's Kitchen is out now. So if you haven't got a copy, make sure you pick it up online or in all good book stores. Let's kick off. Alan, it's an absolute pleasure to have you here.

Dr Alan Desmond: I'm delighted to be here and thanks for the coffee.

Dr Rupy: Of course. Thank you so much for coming down. It's the first time we're actually meeting each other.

Dr Alan Desmond: Yeah, yeah, so it's good to meet you in person and as I said, the moustache is even more impressive in real life.

Dr Rupy: For the listeners, I'm currently doing Movember at the moment and it's the final week, and I'm actually looking forward to getting rid of this.

Dr Alan Desmond: Yeah, it's all for a good cause though, so well done.

Dr Rupy: Yeah, thanks. Yeah, it's getting a little bit long now, but the first time we actually talked to each other was via Instagram. You sent me this wonderful YouTube lecture video that you did at a conference earlier this year.

Dr Alan Desmond: That's right. That's right.

Dr Rupy: And that was all about inflammatory bowel disease.

Dr Alan Desmond: Yeah, exactly. So I'm a gastroenterologist, so I treat patients with GI problems. I'm a gut health expert, but one of the diseases that I spend a lot of my time thinking about and a lot of the patients I meet have this condition, is inflammatory bowel disease. So I guess we'd probably talk about a few of the topics that I covered in that lecture today. But I think essentially, I mean what you're all about is the power of healthy eating and the power of the food on your plate to determine your health and longevity and quality of life and everything. And I think IBD, inflammatory bowel diseases, are a great example of a kind of a modern disease that's become increasingly common and is in many ways a lifestyle disease. And certainly the food on our plate can do a huge amount in terms of preventing and perhaps even treating these conditions.

Dr Rupy: Yeah, we were talking a little bit before actually the podcast where you thought, you know, inflammatory bowel diseases, which we'll go into explaining exactly what they are in a second, could really be the poster boy for how lifestyle and diet can really be influential, right?

Dr Alan Desmond: Absolutely. I guess we hear a lot, I mean deservedly so, but we hear a lot about cardiovascular disease, type two diabetes and obesity, those being the main drivers of loss of healthy years lived in the Western world and main causes of premature morbidity and mortality. But right alongside those, I would place inflammatory bowel disease because the evidence base there that diet and lifestyle have a real role to play in these conditions, and also the evidence that the genetics are there, but they really rather load the gun and then lifestyle pulls the trigger. The evidence around inflammatory bowel disease is growing and growing and is entering the mainstream now.

Dr Rupy: And I think just for the listeners, if you're interested in the lecture, I will post that in the show notes on my website, thedoctorskitchen.com, so you can have a click through and watch Dr Alan in action there. But why don't we, why don't we crack on and just define exactly what we mean by inflammatory bowel disease, Crohn's, colitis.

Dr Alan Desmond: Okay, so predominantly when we say IBD or inflammatory bowel disease, we're talking about two different conditions: ulcerative colitis and Crohn's disease. So in both of these conditions, parts of the gastrointestinal tract become red and inflamed and sore. And I guess that's it in its most basic description. In ulcerative colitis, the redness and the soreness is limited to the large bowel or colon. And in Crohn's disease, the redness and soreness can occur anywhere in the gastrointestinal tract, anywhere from the mouth to the stomach, to the small bowel, to the large bowel, and even around the back passage around the anus. But in most cases of Crohn's disease, the inflammation is in the large bowel or small bowel. Crohn's disease can be a bit more severe because the inflammation goes beyond the gut, goes deep through the wall of the gut and can actually go into adjacent structures. So those are the inflammatory bowel diseases. And as you can imagine, if you have sections of your digestive tract that are red or sore or inflamed or infected all the time, it has a huge impact on your quality of life, your ability to enjoy food, your ability to go to work, go to school. And most patients with inflammatory bowel disease, particularly Crohn's disease, would not describe themselves as being in good health.

Dr Rupy: Yeah, yeah. And this is something that we are seeing a lot more of, right, over the last few decades?

Dr Alan Desmond: Hugely. And I mean, that's part of the clue because when I was in university in medical school, what year did you graduate medical school?

Dr Rupy: 2009.

Dr Alan Desmond: 2009. Yeah, nine years ago. Young. So I graduated 2001. And when I was in medical school, we were taught that inflammatory bowel disease was a classic autoimmune condition, that patients with these conditions had gotten unlucky in the genetic lottery. There was something wrong with their genes, so their immune system was out of whack and was attacking their bowel and causing damage to their bowel.

Dr Rupy: And that's essentially a sort of definition of what an autoimmune issue is.

Dr Alan Desmond: It's your own immune system. It's probably genetic. We'll give you some medicine. But what we now know in 2018 is it's a bit more complex than that. And to put the genetics question to bed, a couple of years ago, this huge international group, the IBD Genetics Consortium, did a full genetic analysis on 30,000 people with IBD from around the world. So it's one of the biggest genetic studies done on a chronic disease ever. And what did they find? Well, they found a couple of genes that could perhaps predispose to getting inflammatory bowel disease, and they found a couple of genes that could predict which part of your gut was going to be affected. But in terms of predicting how severe your disease was going to be, and who was going to need the high-level medications, who was going to need surgery, who was going to need parts of their bowel removed, how severe the disease was going to be overall, the genetics didn't tell them anything. So what was really interesting in that paper was even for these scientists who'd spent years doing cutting-edge genetic analysis on 30,000 individuals, in their summary paper in the discussion, it says the genetic signals that we've identified have a limited role to play in the severity of this disease. Lifestyle, diet and smoking are more important. And that's coming from the genetics gurus.

Dr Rupy: I just want to pull back one of the things that you talked about we mentioned at the start. Most IBD sufferers wouldn't describe themselves in good health. And I think that's really a signal of how important the gut system is to digesting nutrients, digesting food, obviously, modulating inflammation. Why don't we talk a little bit about the function of the gastrointestinal system and why this can lead to so many issues?

Dr Alan Desmond: Well, if you think about your day-to-day, I mean, you're obviously a big foodie, but really everybody's a big foodie. Everyone gets up in the morning, they have breakfast, they go and have lunch, they go and have their tea. And if you've got sections of your bowel that are inflamed, not only are you losing the ability to absorb nutrients, and not only are you reducing your energy intake, leading to weight loss and poor energy levels, and not only are you needing to rush for the toilet five or six or seven or eight or nine or 10 times a day, you've also lost a key part of the enjoyment of your day. You can't sit down for a meal with someone, maybe. You can't go for a meal at someone's house. And we know, and really the next factor I was going to say is the thing that kind of drove me to start reviewing the evidence so I could give my patients some evidence-based answers. We know that the vast majority of patients who have ulcerative colitis or Crohn's disease have issues around food. So they suffer from having had a lack of evidence-based professional guidance from their health professional. So they're either trying to go it alone or they're looking for resources online and they're trying to figure out what food makes me feel good, what food makes me feel bad. And sometimes there isn't a clear answer to that. So patients with IBD will often, when you really look at their eating habits, you'll see that they're practicing food avoidance and food inclusion and that they're even practicing binging on foods that they suspect are harmful, but they just really want to eat them. So in many ways, through no fault of their own, they're displaying these abnormal eating patterns, which they've learned over years of trying to figure it out.

Dr Rupy: Yeah, and I think when we as professionals don't talk about this subject, we allow a vacuum of information that is filled up by Dr Google and a lots of other people online who are perhaps spreading the wrong message. And just to bring a patient anecdote, I had a guy come in a few months ago now, and he had a flare up of his colitis. He, you know, went through the whole motions. He didn't need to be admitted. He was actually fairly systemically well. And I spoke to his gastroenterologist. I spoke to him about his interest in diet and IBD. And he actually didn't, he wasn't aware of anything, first of all, but he wasn't actually interested in it either. And his diet was pretty appalling. It was pretty much a standard American or standard Western diet in all features, in all categories. And just starting the conversation with this person and presenting a way of improving his symptoms alongside conventional treatments, I don't like the word conventional, but I have to use it, he was super interested. So there's actually a huge population outside those who are interested in diet and lifestyle for helping their conditions that would benefit, that would otherwise not look for it.

Dr Alan Desmond: You're right. And that goes beyond IBD, doesn't it? I mean, starting that conversation can often be a real catalyst. So when I see patients at clinic, pretty much whatever I'm seeing them with, whether they've got unexplained abdominal symptoms or whether they've got IBD, or whether they've got a pretty clear-cut issue that we can sort out pretty quickly, I always take a social history. So I always ask about alcohol and cigarettes and drug use, but I also ask how many pieces of fruit do you eat per day, how many servings of veg do you eat per day, and how many servings of whole grains do you eat per day? And that takes me about five seconds. And it starts the conversation. And I've had patients who've come to see me who've turned out to have a small surgical problem, maybe they found a diverticular disease or a Meckel's diverticulum or something. But they come back to see me a few months later to go through the results. And I'll have kind of forgotten that I've given them some pointers towards healthy eating. And it just happened this week actually. So I saw a lady, done and dusted, sorted. She attended with her husband for a follow-up appointment. And as she was getting up to leave, she said, oh, by the way, my diabetic control has never been better, my cholesterol is low, and we've both lost weight because we're eating beans and greens and legumes and we really took your advice to heart.

Dr Rupy: That's fantastic.

Dr Alan Desmond: And I didn't have to spend a lot of time doing that. I just had to start the conversation. I've got some online resources on my clinic website that I point my patients to, and then they'll do the, they'll do the work.

Dr Rupy: That's brilliant. And I think that's a really good clinical pearl. I know there's a lot of doctors and medical students and those who are interested in going into medicine who listen to this podcast. It takes you 15 seconds to do that diet history, and it's super, super important. And actually, just highlighting to the person in front of you how much they are eating of those three particular categories is enough. And like you said, you didn't realise that you even had those sort of conversations and they did the work anyway.

Dr Alan Desmond: Well, I've got an opener because I'm a gastroenterologist, okay? So most of my patients have GI problems. But I got to say when I see patients who've got unexplained abdominal symptoms, so they've had some important investigations, so we know that they don't have something dreadful going on in their GI tract, but they're still not feeling better. I can ask those three questions and the answers might be, I have an apple every few days, I don't like vegetables, and I don't eat any whole grains because carbs make you fat. And then we can go a little bit further and they're drinking two pints of milk a day and drinking 15 pints at the weekend of alcohol. Now, I'm not blaming that person because that's pretty standard, okay? And that's how people feel they should eat and live and that that's fine. I'm not trying to lecture anyone. But if those are the answers that I get, and they often are, then it's no wonder this person's got bloating and sluggish bowel habit. I mean, we live in a country here in the UK where 55% of calories come from ultra-processed foods, which don't have any phytonutrients or fibre in them, where the average bacon consumption is 5 kilos per person per year, where the majority of people aren't getting anywhere near the recommended daily intake of fibre of 30 grams a day. It's more like 14 or 15 grams a day. So those three questions that I mentioned a minute ago, almost always turn up something that you can, and it's really to the benefit of the patient because sometimes they haven't heard that before.

Dr Rupy: I didn't realise the proportion of calories is 55% from ultra-processed food. That's, that's incredible.

Dr Alan Desmond: Yeah, and I think about 9 or 10% from fruit and vegetables.

Dr Rupy: And so there is so much scope for doing good with this, which is super interesting. We're going to bring it back to inflammatory bowel disease.

Dr Alan Desmond: So, so I mean that, in a way we're talking about inflammatory bowel disease because having inflammatory bowel disease, as you've alluded to, isn't a straightforward thing for patients. They're often on a lot of medications and steroids and immunosuppressants and injected biologic drugs, which are fantastic, and I prescribe them all the time, and they've definitely got a place in the management of inflammatory bowel disease. But also patients with Crohn's disease, about 50% of them will end up having surgery to remove part of their bowel, and about 15% of patients with ulcerative colitis will end up losing their large bowel and having a colectomy. So these are serious diseases. And just remember now, this is one in 200 people. This isn't rare. This is so common now, and it was so rare 50 or 60 years ago. And there's a real strong evidence base now that's entered the mainstream in gastroenterology, and it tells us that there's certain features of the current dietary patterns that we all enjoy that aren't helpful for inflammatory bowel disease. And I guess the three main things, and I've alluded to them already, would be fibre intake, the intake of ultra-processed foods, and the intake of meat and dairy. So just a quick word on each of those, I guess. We know that fibre protects us from developing inflammatory bowel disease. We know from the Harvard Nurses' study in the United States, when they followed up a large group of nurses, that those nurses who were getting near to the standard requirement of 30 grams, about 27 grams a day, reduced their risk of getting inflammatory bowel disease by 40%. So fibre protects. So why would fibre protect you from inflammatory bowel disease? Fibre is just really important for health in general and the health of the gut microbiome. When we eat fruit and vegetables, we're really eating fibre and these microbiome-available carbohydrates that make their way down to our large bowel. The bacteria in our bowel turn them into short-chain fatty acids. And not only do short-chain fatty acids help us to control our body weight, help us to control our blood sugars, they also help the immune regulation of the gut, recruiting these T-regulatory T-cells to help dampen down too much immune activity in the gut, but also providing a source of energy to the cells that line our gut to maintain the healthy gut barrier, and also encouraging our gut to produce enough mucus to keep the bacteria off the surface of the gut so that the immune system doesn't get triggered. So eating enough fibre is just really important in preventing inflammatory bowel disease.

Dr Rupy: There's been a prevailing sort of argument that I've had from a lot of patients actually, they've been advised by some medical practitioners to go on a low fibre diet. And I'm sure that's something you've come across.

Dr Alan Desmond: There probably is a limited role for the low fibre or low residue diet, but I think it's for the great minority of patients. So if you've got Crohn's disease with narrowings and strictures that are in your bowel and haven't yet been removed by surgery or reversed with medication, then if you bulk out your intestinal content, you will probably develop symptoms and run into trouble. So for those few patients, then yes, it can be useful. But the problem that I see all the time is that concept is broadened out to all patients with inflammatory bowel disease. And I guess the logic is, you've got ulcerative colitis, you're going to the loo eight times a day. Why don't we make you a bit constipated and you'll feel better?

Dr Rupy: Which is kind of counterintuitive if you look at everything we've just talked about.

Dr Alan Desmond: It is counterintuitive because you're taking all the healthy stuff that helps to ameliorate the disease process and you're making it worse, but you're making the patient constipated. You may as well give them codeine. It'll make them, it'll have the same net benefit. And I'm not advocating giving codeine, but it might even cause less harm, who knows.

Dr Rupy: Just for the listeners, codeine is an opioid-based painkiller that can cause constipation.

Dr Alan Desmond: Absolutely. So I spend a lot of time taking patients off low fibre diet. In fact, there was a nice study done in the States a couple of years ago where they took a relatively small number of patients with inflammatory bowel disease who were also on the standard low fibre diet, and they put them, they gave them all, I think just about 15 grams of fibre a day and educated them about the overall health benefits of fibre. And guess what? They all felt better and their GI symptoms improved. In fact, there isn't any evidence base for the low fibre diet. It's very much sort of magical thinking.

Dr Rupy: It's very hearsay, and I find that a lot within medicine as well, not even talking about just gastroenterology, but in lots of other fields, the prevailing bias is sort of just passed down from patient to patient, but also medic to medic as well. And at the end of the day, you can try and find out where this came from, and you can't find an evidence-based answer.

Dr Alan Desmond: Well, the last time they did randomized control trials on low fibre diet in inflammatory bowel disease, Ronald Reagan was the president of the United States. And even then, those studies showed no benefit, probably showed some harm. But they still persist to the day, to today. So that's fibre. So then the next characteristic of the modern diet that we've alluded to already is the intake of ultra-processed foods. So we eat an awful lot of ultra-processed foods in this country and in the United States and in Australia. And I'm picking those three countries out because those are the countries with pretty high prevalences of inflammatory bowel disease. So when we eat ultra-processed foods, we're taking in things that aren't actually food.

Dr Rupy: Just to define ultra-processed food, that's one where it's been modulated very, very far from its original whole food state and likely had a number of different additives added to it in the form of stabilizers, sugars, salt, and refined industrial oils.

Dr Alan Desmond: Yeah, exactly. So you're talking about food that can sit on the shelf. You're talking about a cake that can sit on the shelf for two weeks, and then you buy it and you open it and it's moist and soft. So it's not moist and soft because it's been baked lovingly. It's moist and soft because it's full of emulsifiers and sweeteners and preservatives.

Dr Rupy: I'm just having a flashback of all the cakes that I've eaten on NHS wards that a very loving patient or a nurse has brought in because we're on nights or whatever.

Dr Alan Desmond: Often those are home baking, aren't they? Often that's home baking, so I think you're okay. They're very unlikely to be adding polysorbate 80 or carboxymethyl cellulose or maltodextrin in their home kitchen.

Dr Rupy: I know the ones that I get from supermarkets that I can't name, probably not those, but yeah.

Dr Alan Desmond: Yeah, but so if we look at those things, what effect do those things have on our gut microbiome and our gut health? There's some very technical papers showing under electron microscopy that if you take a section of gut from a person who's got Crohn's disease and you expose it to dietary concentrations of emulsifiers like polysorbate 80, you can accelerate aspects of the disease process, particularly the adherence and invasion of certain bacteria that can provoke the inflammatory process. And there's similarly papers showing that if you do the same experiment and you take an artificial sweetener like maltodextrin, which is in almost everything, you do the same thing. You magnify the disease process. So not only do processed foods that have 9 to 15 to 20 ingredients on the back, most of which you don't really know what they are, not only do those foods predispose to developing inflammatory bowel disease, but they probably also aggravate the disease process in patients who have inflammatory bowel disease. In fact, the evidence for emulsifiers, which you'll find in lots of foods, soft-whipped ice cream, cottage cheese, even purportedly healthy foods, like a lot of plant-based milks will have emulsifiers added to make them feel creamy in the mouth. So the evidence showing the deleterious effect these have in terms of inflammatory bowel disease is so well documented that a few years ago, a team of researchers wrote a paper to the journal of Crohn's and Colitis saying, we've cracked it, guys. Emulsifiers are causing Crohn's disease. And in a way they were right, but I think it's emulsifiers within the whole picture of how we now eat.

Dr Rupy: I think it's important to note that scientists have a habit of doing that, I think, in papers that I've read. They're just like, we've, that's it. We've found it. We just need to remove that and that's it. And like we alluded to at the start, you know, this is a polygenic disease. It's an increasingly complex pathology behind what's driving it and what may work for some patients may not work for others either.

Dr Alan Desmond: No, you're right. And it's never a one thing and there isn't ever one single solution to gastrointestinal problems, whatever the cause. It's usually multifactorial input that has causing the problems and symptoms. But I think certainly these guiding principles can be really useful. So we've talked about fibre, we've talked about emulsifiers, and I guess the...

Dr Rupy: I just wanted to add one more thing about emulsifiers. I had a patient who came in, I think, and they've been trying a vegetarian vegan diet for about 30 days or so, and they didn't have inflammatory bowel disease, but they felt some, definitely some gut symptoms and definitely felt worse in themselves. And I remember just asking them what they were eating, and it was a lot of healthy junk food, like I like to say. It's the ultra-processed foods that have plenty of additives in, but are marketed as very healthy. And this is an issue that I see in a lot of wellness festivals that I go to actually, a lot of branding in the supermarkets as well. And I think a lot more people need to be aware of just because something is in a nice recyclable brand brown packet, it doesn't ultimately mean it's going to be healthy for you.

Dr Alan Desmond: You're absolutely right. I think the my experience with my patients with inflammatory bowel disease has led me to become a very strong advocate for a whole food plant-based diet. And the emphasis there is on whole food. And you're quite right. You can say, well, I'm going to go, I'm going to go vegan, I'm going to go plant-based because I've heard it's really healthy. But I think there are certain benefits to eliminating meat and dairy from your diet beyond what you get from other whole food plant-based foods. But a huge part of the healthful impact is in fact that you're eating whole foods. I mean, on your, all the food that you prepare and that you share online, etc, shows that in a great way. So that's all healthy whole food knocked together in a few minutes, probably really cheap, and probably tastes really delicious.

Dr Rupy: Oh, one day I'll definitely cook for you, Alan. Now I've got that on recording, I'm just going to keep it.

Dr Alan Desmond: Yeah, that's the whole podcast. So, so meat and dairy. So does meat and dairy have a role to play in inflammatory bowel disease? Well, again, the first clues come from the epidemiological data. And as I've said, Crohn's disease and colitis used to be really rare in the 20th century, and now they're really common. So it exploded here in Europe in the late 20th century, but it exploded a little bit later in countries that were industrialized a little bit later, like Japan and Brazil and Egypt. So we've got really convincing epidemiological data, particularly from Japan, showing that as meat and dairy consumption went up, because they would traditionally eat a very plant-based diet, the rates of Crohn's disease and then ulcerative colitis went up. We've also got data from France, but closer to home. So the E3N study, which followed middle-aged females, I think for about 25 years and looked at their dietary patterns and health outcomes. And they found that the French females included in that study, if you were in the top group for meat consumption, your risk of developing inflammatory bowel disease was tripled. So why would that be? So why would meat and dairy predispose you to developing inflammatory bowel disease? A team of researchers in 2014 gave a really interesting answer to that question. So they took a group of volunteers and for four days, they put them on kind of the carnivore diet.

Dr Rupy: Oh right, yeah, I've heard about this.

Dr Alan Desmond: So this was before people started talking about the carnivore diet, but essentially, they put these volunteers on a diet of meat and dairy predominantly for just four days.

Dr Rupy: Were these healthy controls?

Dr Alan Desmond: Healthy, healthy volunteers who were omnivorous at baseline. So they put them on a very meat-heavy diet. And within just four days, looking at their microbiome, they saw a significant decrease in microbiome diversity, which is a bad thing. And they saw an outgrowth of bacterial subtypes that are capable of triggering inflammatory bowel disease. So bacteria with names like Bilophila wadsworthia, which we know from animal studies can trigger inflammatory bowel disease in genetically susceptible animal models of the disease. So that was a nice demonstration of how a dietary change to heavy meat and dairy kind of gives one mechanism for the change we've seen in populations as they include more meat and dairy in their diet. And asking patients with inflammatory bowel disease to reduce their dairy intake isn't controversial. We know that there's an increased risk of lactose intolerance amongst IBD populations, for sure, particularly amongst Crohn's disease. And one of the trailblazers in the diagnosis, treatment and management of inflammatory bowel disease was Professor Sidney Truelove back at Oxford, where I trained for a little bit. But Sidney Truelove was one of the leading lights in IBD treatment in the 60s, 70s, 80s. And in 1964, he published a paper in British Medical Journal just detailing how he'd identified that in a subset of his patients with ulcerative colitis who he couldn't get better, the standard treatments at the time were mostly steroid-based, that he was putting them on a dairy-free diet and they were getting better. And then if they reintroduced dairy, they were getting worse. So he didn't quite know the mechanism. He proposed it was something to do with the fat and the protein, but now all these years later, we have real insight into that mechanism. So I've no hesitation asking my patients to take dairy out of their diet.

Dr Rupy: Okay. And so we're talking a bit about meat as well. So meat and the, it's interesting looking at the studies because they they clump a lot of the issues around whole foods, ultra-processed foods and meat together. Would you say that that can confuse the data a bit around meat or?

Dr Alan Desmond: As in you're talking about confounders there. Yeah, well, it's always difficult when you're looking at dietary risk factors for a disease because you've got to correct for other behaviors. But I think in the papers where they really try and get as much diet and lifestyle information as possible from their patients and then try to or the participants and then try to correct for that, there still is a signal that animal protein consumption is a risk factor for developing inflammatory bowel disease. And we still have mechanisms that can explain why. We've also got the issue around heme iron, which we can only get from eating meat. So heme iron within the gastrointestinal lumen is pro-inflammatory.

Dr Rupy: And particularly for colitis.

Dr Alan Desmond: Particularly for colitis, but it's also a risk factor for colon cancer. So the more heme iron and animal protein you consume, the higher your risk of colon cancer. So when I ask my patients to try to get some fibre in their diet, and that can be a bit of a challenge for patients with inflammatory bowel disease, they may need to work with their dietitian to find a level. I'm not saying they need to get to the 30 grams a day, but I certainly don't want them excluding fibre to try and ameliorate their symptoms. When I ask them to have some fruits and vegetables in their diet, when I ask them to take the ultra-processed foods out of their diet, and when I ask them to try and move to a more plant-based sources of protein and try and take out particularly the processed meats and the red meats, and maybe just get down to poultry, and then if they feel they can move beyond that, to move beyond with confidence, I know that I'm giving them evidence-based recommendations and we're answering that age-old question that the patients always say to me when I explain to them about their new diagnosis, they always say, is there anything I can do with diet? And there's a lot you can do with diet. The principles that I've outlined are actually being used now to treat inflammatory bowel disease. So you've just come back from Israel. There's a great pediatric gastroenterologist there called Professor Ari Levine, who's been using a plant-based diet regimen to treat patients with Crohn's disease and ulcerative colitis for years and has published on it. So his diet intervention is based around the principles that we've just described. It really restricts animal protein intake and cuts out dairy and processed foods and emulsifiers, etc, etc. And he has published two landmark papers, one paper on newly diagnosed young people with Crohn's with Crohn's disease, and another paper on patients, including children and young adults who've had Crohn's disease for quite a long time and are failing therapy. So two distinct groups there. And he has used his dietary intervention to get response and remission rates that are better than we can achieve with medications.

Dr Rupy: I remember actually, I think you pulled it up in the lecture that I'm going to link to in the show notes, looking at the remission or the reduction in CRP, which is a measure of inflammation in the body and we use it as a marker for disease activity in inflammatory bowel disease. So it's a pretty impressive result. It was a small sample size, I think it was about 60 patients or so.

Dr Alan Desmond: Yeah, I think, I think they've published about that number. And when you speak to Professor Levine, he's obviously using it a lot more, a lot more extensively than that in his treatment of his patients. And when you think about it, that sort of treatment regimen, if it can significantly reduce disease activity, for some patients, they might not need medications, but for most patients, they'll just end up needing less medication and end up going, end up going on less of the more advanced medications, which are great, and I prescribe them all the time, things like azathioprine, six-mercaptopurine, infliximab, adalimumab, ustekinumab. All the mabs, we use them all and they've, they, I mean, don't get me wrong, these have a really important place to play, but I think if we're not also covering the evidence-based dietary recommendations, we're missing a trick. There's also a professor in Japan called Professor Chiba, who's published really impressive results in terms of maintenance of remission in patients with Crohn's disease. And in fact, at his hospital in Japan now, if you have inflammatory bowel disease and you're under his care, he'll admit you to hospital for a week to teach you how to cook plant-based meals.

Dr Rupy: Sounds like a guy after my own heart.

Dr Alan Desmond: Yeah, absolutely. So he, exactly. So that, so he is, his hospital has put evidence-based dietary intervention right up on front when they're treating their patients with inflammatory bowel disease. And at my own center in Devon, at the hospital I work at, we are in the midst of getting ready to launch our own little study where we're going to be offering our patients with Crohn's disease the opportunity to take part in a six-week dietary intervention, very much modeled after Professor Chiba and Professor Ari Levine. We're going to randomize people to standard of care or dietary intervention. And if we're able to replicate the results that we've seen in the literature, it's going to be a game changer. And it's going to be hopefully a game changer within the NHS because not only are we going to be able to give our patients some real-life tools that they can use on a day-to-day basis to help them to manage their condition, it's also going to save the NHS money.

Dr Rupy: Tons of money.

Dr Alan Desmond: Which is the bottom line, unfortunately. And I mean, I know you're involved in NHS innovation, and part of innovation is getting better outcomes for patients, but it's also doing it in a more cost-effective manner, which the NHS has to do because the NHS has got a finite budget. So if we take a patient with a GI condition, not necessarily, well, let's say Crohn's disease, if we're able to significantly improve their disease activity and reduce their symptoms over a 12-month period, and during that 12-month period, they have to sit down with a dietitian once a month, which is a lot, okay? That's going to cost our center several hundred pounds. If we can control their disease or help them to control their disease to the extent that they don't end up on one of these advanced biologic drugs, we're saving about 12 to 15,000 pounds a year.

Dr Rupy: Yes, exactly. Yeah.

Dr Alan Desmond: Per patient.

Dr Rupy: Yes, exactly. Yeah.

Dr Alan Desmond: Absolutely. And I think, I'm like you, I'm a real advocate for dietary and lifestyle intervention, but I've come at it through the from the angle of trying to answer my patient's questions and improve their quality of life. But if you want to drive change in the NHS, you've got to balance the books.

Dr Rupy: Yes, exactly. Yeah. And I think balancing the books is, although it's quite uncomfortable for us as clinicians who are not used to talking about money and the finances of it, it really does come down to that. And if you can show that not only you're saving money, but you're improving the quality of outcomes and you're improving, like you said with the anecdote about the patient who improved their type two diabetes and their cholesterol and the way they feel, then it's a win-win situation for a lot of people. The the the diets that you alluded to, so fibre, removing ultra-processed foods, limiting meat and dairy, there's there's quite a few other studies that look at similar sorts of diets, right? With similar sorts of outcomes.

Dr Alan Desmond: Well, there's a lot, there is a huge amount of dietary protocols out there in the Google sphere. And there's a lot of people out there who've had very positive experiences themselves and are very well motivated and are trying to design programs for the general population to use. Okay? And there's a few particular dietary approaches out there, which the ones that tend to work broadly comply to the principles that I've outlined. So things like the IBD-AID diet, which is used in the United States. But if you are researching a diet online as a treatment for your inflammatory bowel disease, please make sure that it covers having some fruit and vegetables, eliminating processed foods, and cutting down on meat and dairy, because that's where the evidence points very firmly. And I would also encourage people who are looking to make positive dietary change to work with their gastroenterologist and to work with the dietitian at their hospital. I have to say, I still get patients coming to see me who've been to see other gastroenterologists and they tell me their story and then they ask for evidence-based dietary advice and they'll say, you know, I asked my other gastroenterologist and they said diet's got nothing to do with it. So that belief is still out there, but just maybe we'll put a link in the show notes. Just earlier this year, there was a great review of the role of diet in the origin and treatment of inflammatory bowel disease, which appeared in the journal Gut, which is one of our main medical journals for gastroenterology. And that specifically mentions using plant-based dietary intervention.

Dr Rupy: It's a Time magazine for gastroenterology.

Dr Alan Desmond: It's a Time magazine of gastroenterology. So it's very much in the mainstream, but gosh, there's so much to learn in gastroenterology. It's a very dynamic field.

Dr Rupy: Actually, we were talking just before we jumped on the pod about how it is becoming a lot more mainstream now. You're going to conventional gastroenterology conferences and meetings and they are talking about diet and lifestyle. So this is, we're really on the brink of it just becoming the norm that when you go and see any doctor, let alone your gastroenterologist, they're going to be talking about diet and lifestyle.

Dr Alan Desmond: Oh, usually. And the evidence base just supports it so much. And when I ask my patients with inflammatory bowel disease to move towards a more whole food plant-based diet, I know I'm doing them a favor in terms of their overall gut health and in term in broadly speaking, in terms of their general health. Another big part of my job, unfortunately, is dealing with patients with colon cancer. So I perform diagnostic endoscopy, including colonoscopy several days per week. And unfortunately, part of my job is telling people that they've just been diagnosed with a with a colon cancer after the procedure. Now, that's always a difficult conversation to have and it's always going to be a conversation that that patient will remember. But it never gets easier. And every time I have that conversation, I walk out of the room and I reflect on the fact that about a million people every year in the world have that conversation with their doctor, that conversation that says, we've just diagnosed you with colon cancer. And about 40% of those patients live in the USA and Europe, where we only have 13% of the population. So why do the US and Europe have so much colon cancer? Is it because we're genetically different to the rest of the world? You could argue that perhaps, but if you look at African-Americans living in the United States, they've got a very high risk of colon cancer, perhaps one in 20 males getting colon cancer. And if you look at Africans living traditional lifestyles in rural Africa, colon cancer is almost unheard of, probably less than 1% of people will get colon cancer. So why is that?

Dr Rupy: Yeah, there's a big clue there, isn't there?

Dr Alan Desmond: There's a big clue, right? So just about two years ago, there was this really fascinating study on colon cancer risk. And you like, you like the study because this is culinary medicine. So they took two groups of volunteers, a group of African-Americans and a group of people living in rural Africa. So genetically probably quite similar. And at the outset of the study, they very carefully assessed their risk of colon cancer. So everyone had a colonoscopy, everyone had a microbiome analysis. They took samples from their colon lining and they measured a thing called the mucosal proliferation index, which is a measure of your long-term risk of colon cancer. And as well as measuring out their microbiome, they also looked at microbiome products like butyrate, which protects from colon cancer.

Dr Rupy: It's a short-chain fatty acid.

Dr Alan Desmond: Short-chain fatty acid that's produced from certain types of bacteria. Absolutely. And they also looked at conjugated bile acids, which are a risk factor for developing colon cancer. So at the very start of the study, you can predict what they found. The patients or the people from Africa who are eating a traditional plant-based diet had a very low risk profile. And in fact, none of them had pre-cancerous colon polyps. The Americans, genetically similar, diet a world away, half of them already had pre-cancerous colon polyps, and they had all the markers of of a high risk for colon cancer. But what they did next was the fascinating thing. So they did a two-week dietary intervention. The Americans went on two weeks of okra and plantain and South African potato salad. And the Africans went on two weeks of eggs and bacon for breakfast, corned beef hash browns and french fries. And then they reassessed everything. And the risk profiles flipped. So the African people took on the colonic risk or the colon cancer risk of the Americans, and the Americans pretty much reversed their colon cancer risk just in two weeks. And that's extremely powerful because if you take someone living in the US or Europe where we have a very significant rate of colon cancer, for example, in the UK, 41,000 people a year get diagnosed with colon cancer. And if you can get them to eat a more traditional whole food plant-based diet with very little meat, you're really reversing the risk of colon cancer and possibly preventing it. I mean, even Cancer Research UK, who are probably a little bit conservative on these matters, would estimate that about 55% of cases of colon cancer in the UK are caused by either insufficient dietary fibre, obesity, which is diet related, or consumption of meat. So those are huge numbers. So every time I sit down and have that conversation with someone about colon cancer, and I explain everything to them in a sensitive manner, and I explain they're going to need some scans, they may need some surgery, there may even be chemotherapy involved, I do reflect afterwards that this year in the UK, 40,000 people are going to have that conversation. And with the educational tools to help them improve their diet early, earlier, 10 years earlier, 20 years earlier, the number of conversations like that that happen in the UK every year could be cut by half or three quarters or more.

Dr Rupy: Exactly. And this is why I'm actually such an advocate of culinary medicine, which is the nonprofit that we've started trying to educate medical students in medical schools, as well as qualified doctors, that food can be a very powerful tool. And we in this country in particular, in the cities, we're really blessed for access to lots of these traditional foods. There's okra, there's all sorts of exotic vegetables, but there's also the food that we create or we produce in the UK that is fantastically healthy for all people from all backgrounds as well. And it's just about getting them on our plates. And actually, one of the best things that I do is I'm an ambassador for Made in Hackney, which is a community kitchen, they do plant-based foods. Teaching people how to get this kind of diet on a budget. And I think that's the main pushback I get from patients is that healthy eating is expensive, but it's not when you do it the right way.

Dr Alan Desmond: When you alluded to a very good point earlier. So when people want to make a healthy change, they walk into the supermarket and go to the healthy section. You know, they should be walking to the fruit and vegetable section. You know, so they should be buying food that isn't wrapped up in a glossy wrapper that has a picture of someone at the gym. They should be getting some potatoes and beans and, you know, beans and greens. It doesn't have to be complicated. I mean, this morning, you asked me earlier what I had for breakfast this morning. I had whole grain bread and two bananas. Okay, so delicious banana sandwich. There's nothing exotic about a banana sandwich. There's nothing exotic about beans on toast. Okay, so plant-based food doesn't need to be exotic. It can be familiar, it can be interesting, it can be comfort food, and it can be tasty. And overall, it's going to have a huge impact positively on your health.

Dr Rupy: We're going to hold it there for part one. Already, you've had lots of information about inflammatory bowel disease and just to summarize what we're talking about, it's really about getting colours onto your plate, having lots of fibre, and that's lots of different types of fibre that you can get from nuts, seeds, legumes, pulses, lentils. Lots of information on that can be found on my website as well and in the first book, The Doctor's Kitchen. We talked about removing ultra-processed foods. So it really is about eating more whole foods. So potatoes with the skins on, for example, or root vegetables, or even just simple broccoli that hasn't been overprocessed and we lightly steamed it. There's lots of information about how to use food like that in my first book, The Doctor's Kitchen, too. With regard to meat and dairy products, we really want to be lowering our intake of those. As a general rule of thumb, we eat way too much of these products and having a plant-focused lifestyle is something that I certainly encourage. Phytonutrients, things like greens and the colours that you find in your fresh fruit and vegetables include incredible phytonutrients like indole-3-carbinol, sulforaphane, and these have been shown to reduce inflammation, particularly in the gut, which is why it might be useful for inflammatory bowel disease. If I was to recommend one recipe from my book, The Doctor's Kitchen, it would be the Zatar bowl. This has got lots of different colours, lots of different grains, whole grains in their whole form, and it's super simple to make. Make sure you do check it out. And make sure you're subscribed so you don't miss part two because we're going to be talking about colitis again, but also colon cancer, and we also do a rapid round where we ask the most common questions that this gastroenterologist gets asked all the time, Dr Alan, and also some of your questions too. See you next time.

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