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Jonathan Wolf
Welcome to Zoe Science and Nutrition, where world leading scientists explain how their research.
Christopher Gardner
Can improve your health.
Jonathan Wolf
Too much of the wrong foods leads to chronic inflammation, which increases your risk of many diseases, including arthritis, which now afflicts one in five people. Recent research suggests it also plays a crucial role in cancer. But what if there was a way to turn back the clock? A groundbreaking new study reveals that the right dietary intervention could reverse arthritis symptoms, reduce pain and enhance physical function. And this reduction in inflammation could reduce your risk of other deadly diseases like heart disease and even cancer. And today's guest has already seen these transformative results in her own patients. Dr. Tomiko Katsumoto is a professor of rheumatology and immunology at Stanford University. In today's episode, she'll reveal the culprit behind this huge rise in chronic diseases. And she'll share a new diet that fights inflammation and shields us from the threat of ill health. You'll leave this episode with a list of foods that unlock a healthier life. And if you're looking for food recommendations that actually make you feel good, then let me suggest you check out Zoe's personalized nutrition program. Because the food you eat isn't only making you tired, it's making you sick. Did you know that 60% of our calories now come from ultra processed foods? They're cheap, they're often loaded with sugar and saturated fats. They can last on your shelf for years. And they're engineered to keep you hooked. But every day there's more evidence that links ultra processed food with obesity, cancer, depression and many other diseases.
Christopher Gardner
We live with a food system that's rigged against us.
Jonathan Wolf
Zoe's personalized nutrition program helps you break free. We point you towards the smartest food choices for you. And we'll make it easy too. Visit Zoe.com to get your at home test kit and personalised nutrition program today. Okay, let's get on with Today's episode with Dr. Tomiko Katsumoto.
Christopher Gardner
Tomiko, thank you so much for joining me today.
Dr. Tomiko Katsumoto
Thank you for having me. Excited to be here.
Christopher Gardner
I think it'll be a lot of fun. And right at the start, I think you know, because you told me you're a regular listener yourself. We have a tradition here at Zoe where we always start with a quick fire round of questions. Are you willing to give it a go?
Dr. Tomiko Katsumoto
Absolutely.
Christopher Gardner
All right, so remember, yes or no or if you absolutely have to, a one sentence answer.
Jonathan Wolf
Are more people developing arthritis?
Dr. Tomiko Katsumoto
Yes.
Jonathan Wolf
Does the food we eat play an important role in arthritis?
Dr. Tomiko Katsumoto
Yes.
Jonathan Wolf
If you're Starting to feel symptoms.
Christopher Gardner
Is full blown arthritis inevitable?
Dr. Tomiko Katsumoto
Not necessarily.
Jonathan Wolf
Could you reverse arthritis with the right foods?
Dr. Tomiko Katsumoto
Yes.
Jonathan Wolf
And finally.
Christopher Gardner
And you can have a whole sentence. Tomiko, what's the biggest myth when it comes to treating arthritis?
Dr. Tomiko Katsumoto
I think the biggest myth is that there's nothing you can do to change your arthritis course. I think there are actually a lot of things that we are all capable of doing through diet, lifestyle, et cetera, that can make a difference.
Christopher Gardner
You know, when I was growing up, everyone talked about tobacco as a leading cause of chronic disease. And today we're sitting here and we're basically talking about poor nutrition as the biggest cause of this. And you know, it's been eight years since I co founded, Zoe, and I think every year I've just got more and more shocked at the way in which the food that we're eating, you know, across the western world is making us so sick, but also just discovering each year about ways in which it affects us that I had no idea about. So today we're talking to you as a professor of immunology and rheumatology at Stanford about arthritis and how it's linked to food. And I never would have guessed when I found it, Zoe, that it could have anything to do with food. In fact, I would have said that was, you know, like crazy, totally non scientific. So it's amazing how much I think my understanding has changed. What is arthritis and how does that relate to this concept of implementation inflammation, which I know is a lot about what you study, you and me both.
Dr. Tomiko Katsumoto
I think we in medical school were not taught about the role that diet and all these other lifestyle factors play in a lot of our inflammatory diseases. I'm a rheumatologist, so I take care of patients with arthritis with a lot of other inflammation of other organs. So rheumatoid arthritis, lupus vasculitis, you know, psoriatic arthritis, you name it. I think arthritis is complex. Basically, our joints are generally protected areas where you've got your bone, you've got a synovial lining, you know, you've got this nice joint capsule that is lubricated so that it allows us to move freely. The problem is with inflammation, there can actually be a breach of those protective barriers such that there becomes, you can end up getting inflammation. There's actually connection with the gut and mucosal barriers that play into the inflammation leading to arthritis.
Christopher Gardner
And Tamiko, I know nothing about how my joints work. And I could see you're sort of painting a picture of, I'm sort of imagining Somehow something, I don't know, a bit quite mechanical with some oil running. Is that the right analogy? Is that what you described? Could you just help me to understand a bit?
Dr. Tomiko Katsumoto
Yeah, I think that, you know, it's actually, I'm thinking about this. There's a lot of analogies. We talk a lot. I know Zoe talks a lot about the gut and how there's this important lining of the gut. Similarly, I think you can think about the joint in that there's an important lining called the synovial lining of the joint that can get breached when you end up having, let's say, T cells that are recognizing some of the synovial proteins. So the joint proteins there can actually be what's called an autoimmune attack where your own T cells can end up invading the joint, causing inflammation. It causes a leaky joint, if you will. We've heard about leaky gut, and I think what we've started to learn over the course of. Of research is that these mucosal breaches, for example, in our gut, even in our mouth or oral microbiome, can stimulate certain bacteria that may actually cause our immune system to wake up. T cells that are attacking these specific bugs in our gut, in our mouth, can end up actually getting confused and attacking our joints. So this is a whole hypothesis that's coming to fruition with some very exciting science recently in terms of, you know, how our immune system can be connected to joint inflammation.
Christopher Gardner
So, Tomiko, if I understand rightly, what you're saying is like, I'm not experiencing any arthritis today, so I can sort of move all my joints around and they're able to sort of slide around somehow really smoothly. I'm thinking a bit like a sort of Teflon pan or something like that. But you're saying that what can happen is my own immune system ends up attacking, like, parts of these joints and breaking that Teflon, and then suddenly it's both painful and does not move as smoothly.
Dr. Tomiko Katsumoto
Exactly.
Christopher Gardner
I don't know if I'm stretching this analogy way too far.
Dr. Tomiko Katsumoto
Yes, no, it's a great one. I think that it's either immune attack that can lead to the disruption of this nice synovial barrier that can lead to arthritis. My patients end up getting very swollen, tender, red hot, painful, stiff joints. Other ways that this can happen are through damaged responses. So one thing that a lot of people may have heard about is a condition called gout, and that would be a crystal. There's a crystal called uric acid, which is a byproduct of a lot of cellular metabolism. And those uric acid crystals can end up building up in our joints, and that can end up triggering this inflammatory response as well. So I think that there are different paths leading to arthritis. What we call sort of the acute inflammatory innate response. And then there's a more complex autoimmune mechanism that we were talking about when you have T cells that are attacking the joints. So there's various ways in which arthritis can develop, and we can talk a little bit more about kind of what are the things that set you up for that.
Christopher Gardner
So, Tomiko, how many people are affected by this?
Dr. Tomiko Katsumoto
So it's estimated that about 1 to 2% of our population is affected by rheumatoid arthritis. The numbers for osteoarthritis are much higher in the millions. Psoriatic arthritis, a little less common. But again, I think the important point to note is a lot of these autoimmune inflammatory diseases are on the rise. You know, lupus, for example, is an autoimmune condition that can affect multiple organs, certainly the joints, often the kidneys. And one of the lab tests that we use is called an ana, which is an antinuclear antibody. If you look over time, actually, those numbers are going up. So now in terms of females, actually up to 20% or more of females will have a positive ANA. So there's this increasing incidence of autoimmunity that we're seeing in general. And I think one of the key questions is, why is that happening? What's driving this? I think a key point to make there is that we are not evolving that quickly. Our genetics are not changing. I think what this speaks to is the importance of epigenetics, meaning environmental influences that are changing how these diseases are manifesting. So clearly, I think there's a lot of environmental drivers that are leading to this increased prevalence of arthritis and other chronic inflammatory diseases.
Christopher Gardner
I'd love to get into that. Just before we do that, I was just thinking about my grandmother. So my grandmother had really quite severe arthritis, and she refused to ever complain about it. So it was quite obvious that she was in pain, but she was of that generation that you should never make a fuss. And actually, interesting. Her mother had very severe arthritis as well. So I assume that there is a genetic component in this.
Dr. Tomiko Katsumoto
So, yes, in rheumatoid arthritis, there's something. I'm gonna use a fun term here called shared epitope. There's a specific gene that has been linked clearly to rheumatoid arthritis. There are other types of arthritis. Like there's one called ankylosing spondylitis where it tends to affect the back and also the sacroiliac joints and some of the larger joints. This one of the arthritis types that's more common in males. There's a genetic predisposition there, which is called HLAB27. Maybe some of you have heard about this, but to be honest, when we think about the genetics, I think that relatively speaking, that plays a less contributory role compared to a lot of the environmental factors that are driving arthritis.
Christopher Gardner
Got it. And so what is the experience of someone who's living with arthritis? And I know you've mentioned both osteoarthritis and rheumatoid arthritis. Are they experienced the same or what the difference is? Maybe just help to paint a bit of a picture for people who aren't familiar with this.
Dr. Tomiko Katsumoto
Yeah. So osteoarthritis is unfortunately one of the most common types of arthritis. And we used to call it kind of a wear and tear, degenerative arthritis. Less inflammatory. These are the types of arthritis that can occur in joints that have previously had, for example, an injury. A lot of athletes that have messed up their knees or their hips, whatever that can happen. However, I think we're learning osteoarthritis actually might have a more inflammatory component than we previously realized. It's more common in people that are overweight. It's possibly related in some ways to the fact that they're bearing more weight on those joints. So there may be a mechanical component, but there are other components for osteoarthritis we don't fully understand. For example, the hands can be affected in osteoarthritis. And so clearly we're not bearing weight in our hands. Osteoarthritis is sort of one of the classic most common types, which is less. It's not considered to be truly inflammatory. Rheumatoid arthritis is the most common inflammatory arthritis. And again, I think that we are starting to understand that there are genetic contributions. But more and more, as we move forward, we're learning the environmental components are substantial.
Christopher Gardner
What do you experience as a patient living with osteoarthritis or rheumatoid arthritis?
Dr. Tomiko Katsumoto
Osteoarthritis, I'll call it oa, osteoarthritis, tends to be less inflammatory. People tend to get more and more pain with motion, with using their joints. In contrast, rheumatoid arthritis is considered inflammatory, meaning that people tend to wake up feeling incredibly stiff. Takes a while for them to get up and going. They often feel like they, they need to get their joints moving. A hot shower might really help get them moving. They experience what's called gelling, where you sit down for a prolonged period of time and your joints kind of gel and then as you start to move them, that starts to get them feeling better. But rheumatoid arthritis can be profoundly disabling. The amount of pain, the amount of dysfunction, a lot of patients aren't. For example, if it's affecting your hands, you're not able to open jars or grasp or using your joints the way you normally would like to. It can be very painful in terms of, if it affects your foot joints, it feels like you're walking on marbles or glass in some cases. Back in the day, this used to be a very debilitating condition and people would often end up disabled, in wheelchairs, or really unable to perform their jobs or activities of daily living. I think we've made some significant progress in terms of the treatments that are now available. So I have to say, you know, there's been the advent of disease modifying agents. We use methotrexate, you know, we use hydroxychloroquine. We also use a lot of these biologic agents that are specifically targeting some of these inflammatory cytokines, which is a fancy word for inflammatory proteins. TNF, tumor necrosis factor, interleukin 6. These are some of the inflammatory drivers that lead to the inflammation within the joints.
Christopher Gardner
So you've slightly scared me with all the terminology, Tommy Ko, but what I'm understanding is that firstly, it's tough to live with this. Like it has a big impact on your quality of life.
Dr. Tomiko Katsumoto
Absolutely.
Christopher Gardner
Secondly, the good news is you're saying that medication has moved on a lot from, you know, think about my grandmother and nevermind my great grandmother. So there is a lot that can be done, but it doesn't just make the whole thing disappear.
Dr. Tomiko Katsumoto
So I think people can really have improved quality of life on these medications. But there's a trade off. And the trade off is when we suppress your immune system, you are then more vulnerable to infections. You know, in some cases we worry about cancers, in some cases, you know, we worry about what is the long term impact, right. Of very directly targeting some of these key inflammatory mediators. So that's the concern.
Christopher Gardner
You've talked about inflammation a lot and talked about how not only in rheumatoid arthritis, but you're saying also in osteoarthritis where people have said before there's no inflammation, you're saying, like the latest evidence suggests there is. Could you help us to understand in very simple terms, like what is inflammation and what's going on, that it's clearly causing this very significant sort of attack on my own body.
Dr. Tomiko Katsumoto
These are always difficult concepts, very kind of abstract. I think maybe the best way to distill this would be inflammation can be thought of as a damage repair mechanism. So, for example, right when we cut ourselves, we need inflammation. We need the, you know, white cells to come in and help heal and, you know, heal that wound. When we have an infection, we need inflammation to come in and actually help fight against these invaders, you know, viral, bacterial, fungal. But I think the key problem is that, unfortunately, the way our lives have evolved is we are being constantly exposed to these various inflammatory threats. Now, one of the biggest ones is our diet, and it's driving inflammation that's aberrant, that shouldn't be happening all the time. And so you can imagine that we end up driving this chronic level of inflammation. These inflammatory cytokines talked about, you know, TNF IL6, the ones that we target for arthritis, those are going up and up in response to a lot of the foods that we're eating, a lot of the other environmental insults that we're experiencing. And believe it or not, when we talk about arthritis, like rheumatoid arthritis, this is a systemic inflammatory response. It's not just in our joints, it's our whole body on fire. And so really, it's leading to accelerated cardiovascular disease. It's leading to, you know, a lot of these other metabolic consequences. I think we see in our patients. A lot of them don't just have arthritis. A lot of them also have diabetes and hypertension and cardiovascular disease and accelerated, you know, a lot of them have memory disorders. So I think, thinking about it, I don't like to be reductionist and think of arthritis as just one entity. There's so many comorbidities that come with it, and the common theme underlying it all is inflammation.
Christopher Gardner
I'm really struck by this image that you just said about, like, our whole body is on fire. And so is that a way when you're describing someone living with this, like, permanently raised level of inflammation that's on all the time, That's a very strong metaphor. Like, that's a real way to understand what's going on?
Dr. Tomiko Katsumoto
Yes, I think that, you know, when we measure, for example, one of the biomarkers we use is, you know, esr, which is erythrocyte sedimentation rate, and C reactive protein. And those are often quite high in these conditions. And I'll give an example. So the cardiologists have caught onto this and they are using C reactive protein as a marker for risk for cardiovascular disease. So our patients have very high levels of these inflammatory markers and so you can imagine it is driving inflammation in multiple organ systems, not just the joints.
Jonathan Wolf
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Christopher Gardner
You're saying that we can measure in our blood all of these different chemicals and you're saying there's a whole bunch of them. I think you mentioned crp for example, that are ways to tell like how high are like inflammation is set. And this is, this is sort of like our immune system going like, wow, this thing is really dangerous. You know, ringing the bell for the fire engine and the police and the army and whatever. And you're saying that it's really high with people living arthritis. But we are, we now know that that is like a sign of a lot of risk for damage to your heart, for example as well. Because basically when that this thing is so high somehow like your body's no longer. I'm thinking about like the mayhem at the end of a Hollywood movie after things gone wrong and you've got the SWAT teams, everyone, all the rest of like, no one is able to go to work, no one is able to go home. It's all A mess. And that's sort of what's going on in our body when the inflammation doesn't go back to normal after I've cut my finger.
Dr. Tomiko Katsumoto
That is right.
Christopher Gardner
So so far the picture is a bit bleak. But I know you already talked about how food is an important cause of this problem. You already mentioned that, like inflammation from food, which I think some people listening be like, is that a real thing? And you're saying this is a real thing. But I understand that you're also really interested in food as playing an important protective role and that in particular excited about a breakthrough new clinical trial that the team was telling me about actually earlier this week, which I think is called Plants for Joints.
Dr. Tomiko Katsumoto
Yes.
Christopher Gardner
Could you tell me about that?
Dr. Tomiko Katsumoto
And by joints, we're talking about joints, the anatomic joint, not the other kind of joint. I'm from California. This, this was a very exciting trial. I'm a huge fan of randomized controlled trials. I think this is our highest level of evidence. This is a group, our Dutch colleagues, they ended up randomizing a group of patients with. But they actually did two studies in parallel. They did one in rheumatoid arthritis and they did one in osteoarthritis. To clarify, it was a metabolic associated osteoarthritis. So patients that tended to have metabolic syndrome or maybe overweight. So those patients with OA and so.
Christopher Gardner
Randomized controlled trials are basically the gold standard of scientific testing.
Dr. Tomiko Katsumoto
Yes, they are helpful in that they minimize any confounding bias in terms of the fact that people are put into two different groups. There's an equal chance of whatever intervention working or not and comparing to a placebo provides a robust comparator. And basically what they did was they put them through a lifestyle intervention. And this is absolutely thrilling to me because I'm a huge fan of the American College of Lifestyle Medicine. Just to quickly provide their six pillars of lifestyle medicine. Diet is number one. In addition, exercise, stress reduction, social connections, sleep, and then finally avoidance of risky substances. So those are the six pillars of lifestyle medicine. And essentially what this randomized controlled trial did was put these patients through either the activarm, they called it the Plants for Joints arm that underwent these six lifestyle interventions versus the placebo, which was essentially standard of care. They ran them through this program for 16 weeks. And what they found at the end of the study, and even at eight weeks at the midpoint, they saw dramatic improvements in the patient's joint disease. So for the rheumatoid arthritis patient, the endpoint they looked at is called DAS28. This is disease activity score based on 28 different joints. So you measure swollen and tender joints, you measure the CRP inflammatory marker, you measure how the patient's feeling. And based on that endpoint, which is a very robust endpoint, there was a very statistically highly significant difference in terms of the ra. Patients that underwent this lifestyle program. They looked more deeply to see what was the most likely thing driving this difference. And it was most likely diet. Of course you can't separate out, you know, it was a full holistic intervention of multiple different domains. But anyway, bottom line, I think diet played a huge role. And what they did was they educated these patients on whole food, plant based diets. So minimizing processed foods, minimizing, you know, really, or mostly eliminating animal products, increasing fiber intake and really trying to encompass a very healthy whole food diet. Same thing was done for osteoarthritis. And the reason I got so excited to see the results for osteoarthritis is we don't have great treatments for oa. It's one of the most common conditions, debilitating. A lot of us get it and yet we often don't have good answers. And so the fact that this intervention, this lifestyle intervention showed such a promising result, I think is really exciting for the field.
Christopher Gardner
There was a big impact for both these groups with these different types of arthritis.
Dr. Tomiko Katsumoto
Yes.
Christopher Gardner
Because I know sometimes scientists can get really excited about something that's like, it's statistically significant, but it's like a 2% change. And so the scientists get really excited about it, but it's like a normal person or patient, you're like, well, that doesn't really going to change my life. Like, does this actually make any difference to the symptoms and how they were going to feel after this?
Dr. Tomiko Katsumoto
Yes, this was definitely beyond the minimally important clinical difference. So there was clearly impact on patients lives, quality of lives. What was most exciting, they did a one year follow up of these cohorts and they showed that a lot of these patients were able to get off of their medications.
Christopher Gardner
They were able to actually give up their medications because you were talking about how serious this is.
Dr. Tomiko Katsumoto
Yes.
Christopher Gardner
So that seems rather amazing, which is incredible.
Dr. Tomiko Katsumoto
I think a lot of them ended up gradually deprescribing a lot of their meds. Many of them, a lot of them lost weight, a lot of them improved in terms of their blood pressure, in terms of other cardiovascular lipid profiles, these types of things. But I was most struck by the fact that some of them were able to wean off these medications, which was striking.
Christopher Gardner
Can you help us to understand how this change in what you're eating could suddenly stop your joints being inflamed and in pain? Because, you know, the link is not obvious.
Dr. Tomiko Katsumoto
I think it's complex and multifactorial. Simply speaking, I will say we know a lot of our dietary components, like sugar, you know, a lot of these, you know, saturated fat, processed foods, drives inflammation in various ways. I think one of the primary ways is through how it, you know, how it affects our gut microbiome. I think that, you know, we end up assaulting our important gut barrier with loading it with all this sugar and fat and these emulsifiers and food colors and other processed things that are really insulting the gut barrier and that is leading to this systemic inflammation. A lot of the cytokines, these proteins, inflammatory proteins I talked about earlier, like TNF, like IL6, these go up with poor diet. And I mentioned to you earlier, those are the things that we target with our drugs. And so these things are all related concepts. And so by simply improving our diet, improving our gut health, decreasing the dysbiosis that we experience, I think that that is leading to these improvements in our joints.
Christopher Gardner
You're very focused on measuring this sort of level of inflammation in the body of your patients. You've talked about that quite a lot. You're saying that if I go and eat like a typical western diet, you know, all the hamburgers and all the rest of it, I come back in a year's time, you're going to actually be able to see that in the inflammation, like in my bloodstream with these markers?
Dr. Tomiko Katsumoto
Yes. It's so fascinating. I don't know if you've ever gotten phlebotomized. People draw your blood.
Christopher Gardner
I definitely have.
Dr. Tomiko Katsumoto
But if you get your blood drawn after you eat a big hamburger or a big fried meal or something, I mean, it is striking. Blood normally is nice and deep red and pure, and there's not, you know, if you spin it down, you look at the serum layer, it's a nice clear layer. Literally, minutes after you eat that hamburger full of saturated fat and whatever else is in it, that serum layer becomes cloudy. And it's like all these lipid particles that end up going straight to your liver, causing inflammation. That stuff is coursing through your blood, and it's considered a hazard. Your immune system reacts to that. And that's part of the issue, is that we're getting this dramatic response to saturated fat. It's quite striking.
Christopher Gardner
That's quite a Crazy picture you're painting. So you're saying, like, you can tell if I've just eaten a hamburger. You don't even need to do like the blood test. You can just look at like my blood if you pull it out of my arm and that, that you feel is not good. That is not sort of a normal situation. That's fascinating. So how profound a change were these participants having to go through in order to get this benefit? Were you having to go from like, literally, you know, your normal diet, which has got plenty of meat and of course you eat some french fries and like, nobody's perfect, to like this perfect sort of vegan diet where all you eat is like rabbit food? Like, is that what was required in order to have this impact?
Dr. Tomiko Katsumoto
So dietary adherence, I think was variable. I think they did see better, you know, improvements with those who were able to move towards more whole food, plant based eating patterns. I think so. The intervention did include a lot of dietary counseling and a lot of kind of hand holding. But I will tell you there is a preponderance of data that supports the whole food, plant based diet in terms of improved health outcomes. And I would say, I would not call it rabbit food. I think that there's lots of yummy, delicious, you know, as Christopher would say, Christopher Gardner would say unapologetically delicious food food. There's a lot that can be done in terms of plant based, plant forward, or I should say plant centric eating. But it's so clear to me the data supporting that dietary pattern with positive outcomes.
Christopher Gardner
I guess what I was wondering is, do you need to be perfect in order to get that benefit? Because obviously you're talking about a trial. And I've spoken to other podcast guests who talk about you can do a trial and you can get people to do something quite extreme for, you know, a month or a couple of months, but it's sort of not sustainable. And the question then is if you're not perfect at this. So let's say somebody's listening to this and like, I don't want to be in a position where I never get to eat any red meat again. From your view as a clinician and a scientist, like, do you need to be perfect on this to get this benefit on arthritis?
Dr. Tomiko Katsumoto
You don't need to be perfect. Nobody's perfect. You know, let me tell you some anecdotes that I think are really striking. So I've actually had some very good luck coaching my patients towards more whole food, more plant centric diets. A lot of them have improved. And then what happens is they have a slip up and they gorge on sugar or they gorge on a steak and they will literally feel it in their joints quickly and it's striking.
Christopher Gardner
So at this point, once they've made the change, you're saying that they can literally feel like later in the day or something, the impact on their body of that particular food.
Dr. Tomiko Katsumoto
So fascinating. I've learned so much from my patients. I think some of them, like, you know, when they're really able to kind of get themselves to a really nice kind of homeostatic, balanced point, their joints are doing well and then they slip up and they find trigger foods. It can literally happen in some patients, I mean, within hours or a day or, you know, short periods of time, they can suddenly feel their joints light up. And I think what's so exciting is that the joints, you know, you don't feel your cholesterol going up, you don't feel your glucose. Well, you have CGMs, but you don't feel your hemoglobin A1C rising up. Right. For diabetes. But people feel their joints. And it's really incredible. In my patients who have come with me on this journey towards eating for health, I'm a huge believer in food is medicine and those have done these N of 1 experiments and then they have found, you know, certain trigger foods. So yes, you don't have to be perfect. But it's so fascinating how food can reinforce, you know, what might be driving your underlying inflammation in a very tangible way, which I think is really striking.
Christopher Gardner
I think that's amazing idea that you could actually eat a particular food and just feel it in your joints that it feels bad. Because I think one of the things that is, I think very hard about food is that for most of us, you know, we're surrounded with this environment, with all this delicious ultra processed food everywhere that's been designed by very clever scientists. Right. That you can't stop eating it and mainly you're not really aware of how it's making you feel. But it sounds like you're saying that if you're at the point where you are living with arthritis, in a way you're sort of more sensitized. Clearly our ancestors were quite happy to occasionally eat, you know, honey and fruits and the red meat whenever they could get it. And so it wasn't causing them any problem. And here you're talking about these patients who can sort of like feel the negative impact immediately. What's going on here that they're having this different experience than Our ancestors would have had.
Dr. Tomiko Katsumoto
First of all, I think our ancestors probably had better gut health. And so, you know, I think one thing that's so complicated is that when you have poor gut health, I think that's setting you up for an immune system that's primed to respond to different proteins, different antigens. And like I said, the ones that are in the joint, there are T cells that may end up going to the joint. And so whether the food that we eat is basically triggering those T cells to get activated, you know, whether it's basically because you've got this leaky gut breach of this gut epithelial barrier and your immune system, which is, by the way, the gut has the biggest immune system. And, and whether then those T cells are getting educated to then, you know, they're getting activated and reactivated upon introduction of some of these trigger foods. I mean, that I think is a mechanism that is most likely to explain this gut joint connection.
Christopher Gardner
That's really interesting. So you're saying the microbiome you think is playing this very important role in how the food is then leading to inflammation. Do we know whether there's a positive impact here as well? Have they looked at the microbiome in this study, for example, or, you know, elsewhere and understood whether, you know, by shifting this food, people living with arthritis are actually able to improve the microbiome and that's leading to these improvements?
Dr. Tomiko Katsumoto
Yes, I think it's. The microbiome is a bit of a complex galaxy. I think that there's no one perfect microbiome. But I think one theme that keeps coming through in every study is that diversity of the microbiome is super important. And if we feed our microbiome good foods, we take care of it by eating, again, high fiber, lots of plants, good foods, then the good bugs will proliferate and predominate. And I think that the problem with our industrialized society and our diets is that we really have, unfortunately, a decrease in our gut microbiome diversity, which is a huge problem. And so definitely studies have shown that patients with rheumatoid arthritis and a lot of other inflammatory diseases have a decrease in their microbial diversity in their gut. And then just trying to figure out what are the good bugs. I think there are several different candidates, but it really is the composite mixture of bugs that leads to a good gut microbiome. There's not a one size fits all.
Christopher Gardner
Now, I know we focus a lot on arthritis, but I think sort of taking us through this story with inflammation, I think you've Already explained how much this is touching. Sort of almost all the other diseases. Right. That are likely to affect us. But one you haven't mentioned is something that I understand you're also involved in researching, which is that you're part of a multidisciplinary group that's looking at cancer at Stanford. Is that right?
Dr. Tomiko Katsumoto
Absolutely, yes.
Christopher Gardner
Is there any connection between this sort of chronic inflammation that we're talking about and cancer?
Dr. Tomiko Katsumoto
Definitely. And I think these are incredibly complex topics. But one thing that has come to light recently, in the past less than a decade, is we are learning how important the immune system is in terms of cancer control. And so what's happened is the Nobel Prize was awarded in 2018 for the advent of what are called immune checkpoint inhibitors and to try to kind of distill this down. Basically, the immune checkpoint inhibitors are these molecules, these antibodies, that take the brakes off the immune system. So they inhibit the inhibitors of our immune system. And in doing so, it allows for this very robust immune response to occur. And hopefully it means it's going to stimulate some of those T cells to go attack our cancer cells. Right. Our bodies are constantly surveilling for cancer. We're probably developing little aberrant cells right here as we're sitting, as we speak. And because we hope our immune systems are good, we're clearing those cancer cells. But you can imagine when you have aberrant inflammation, your immune system may be somewhat compromised in clearing those cells. And so we're learning that, for example, cancer is becoming more and more common, and we're seeing it in younger and younger people. And so there's probably a role for the immune system. Again, our gut microbiome, these are so many complicated concepts to try to tie together. But I'll just go back to the checkpoint inhibitor example because I think it's really interesting. So immunotherapy is really helping to stimulate our immune systems to kill our cancers. Unfortunately, our immune systems then can get so activated they can end up attacking different organs of our body as well, including our joints, our skin, our lungs, other places. And one thing that we've learned is that diet plays a really important role in the immunotherapy response. So scientists at MD Anderson have shown some really beautiful data. When they looked at patients with melanoma, which is a type of skin cancer, who were receiving this immunotherapy, they found that the patients who had the most robust response, response to clear their cancer were the ones who were on high fiber diets. And they're finding that the Patients who had the most diverse microbiomes. Right. Those were the patients who ended up having a more effective anti tumor response. And I think other data, we're learning that similarly, I think our gut microbiomes are really important in mediating and tuning our immune system system to prime us to kill off these cancer cells.
Christopher Gardner
Hi. I have a small favor to ask. We want this podcast to reach as many people as possible as we continue our mission to improve the health of millions. And watching this show grow is what motivates the whole team at Zoe to keep up the really hard work of creating new episodes each week.
Jonathan Wolf
So right now, if you could share.
Christopher Gardner
A link to the show with one friend who would benefit from today's information, it would mean a great deal to me.
Jonathan Wolf
Thank you.
Christopher Gardner
You're saying that there's some recent papers looking at patients fighting cancers using these new immunotherapies, and you're saying that the patients on diets with more fiber, which we know is this key thing that feeds the gut microbiome, and also people with this more diverse microbiome, we're actually having a better response when they took this immunotherapy. So it's been more successful for fighting cancer.
Dr. Tomiko Katsumoto
Exactly.
Christopher Gardner
So I'm pretty stunned by that. You're looking at me as though, like, yeah, that's sort of obvious. Is that, like, have we known about that for very long?
Dr. Tomiko Katsumoto
No, we haven't. And no, this was not obvious to me either. I think I'm thrilled because it obviously is concordant with everything we think has been true about the gut microbiome. But I think it raises the issue that really, our microbiome is playing such an important role in modulating our immune system and tuning it to optimize, you know, our health against protecting us from autoimmunity, protecting us from cancer, protecting us from, you know, other infections. I think it's becoming so central to what we call immune homeostasis, you know, the real kind of just the balance of everything in our bodies. So I encourage my patients that have cancer to really be thinking about their diet seriously, because I think that our diets play a huge role in not only response to immunotherapy, but also other cancers as well. We know colon cancer is very closely associated with our diets as well as other GI cancers. So I'll mention to you, the National Cancer institute has identified 13 cancers that have been definitively associated with obesity. And we know obesity is obviously very much associated with our diets. And a lot of these cancers tend to be gastrointestinal GI related cancers, esophagus, stomach, liver, pancreas, gallbladder, and then of course, colon. A lot of the other cancers that are listed on this list of 13 are hormonally driven cancers. So breast, you know, uterine, those types. So I think that, you know, we are starting to really appreciate the role of diet and inflammation that probably plays a really fundamental, you know, role in our protection against these cancers.
Christopher Gardner
I think that's really amazing, a little terrifying because of course, the diets that we are eating, you know, whether I'm here in the States or I'm in the UK or Australia or it doesn't really matter, right. Are really low on the sorts of foods that support our microbiome and really heavy in the sorts of ultra processed foods that are bad. I just want to clarify one thing because you've talked a lot about here about how you might be able to improve your diet if you were fighting cancer or something like that. I think you're also saying that if I am just eating a traditional Western diet, that this is going to be directly leading to this higher inflammation, and that inflammation is then liable to increase my risks of, you know, not just what we talked about before, like the heart disease and arthritis, but also things like cancer.
Dr. Tomiko Katsumoto
Yes. I should mention the WHO has declared that processed meats and red meats are considered carcinogenic. And so, you know, again, we're seeing kind of this incredible uptick in our meat consumption when you look over the past century. And I think we need to keep that in mind, that not only is it not good for the environment to be eating red meat, but it's also really a problem, I think, in terms of just cancer generation. Colon cancer rates are going up. You know, in the United States, we've decreased the age for screening for colon cancer now to 45. Used to be 50, now it's 45. And so I think that our poor Western diets full of ultra processed foods, full of meats, especially red meats, I think that is driving this uptick in cancer that we all need to be wary of.
Christopher Gardner
Tomika, I think you've painted a really strong picture about why the food that we eat can really affect you. And I think having gone in talking very specifically about arthritis, I think you've really pushed it open as well to think about the broader impact. I'd love to talk now about actionable advice, and I'd like to really focus. Like, imagine a listener here is living with arthritis or they know someone who is, and they'd like to go and, you know, share this podcast with them and make sure that it's like really practical. And I understand that you and your colleagues have built a sort of new food pyramid as a way to think about how you could put these sort of anti inflammatory foods into your diet. And it's pretty different from the food pyramid that I grew up with. Could you take me through it?
Dr. Tomiko Katsumoto
You're generous. We haven't built a new food pyramid, but we adhere or we promote a couple food pyramids that I'm particularly keen on. Andrew Weil, who is kind of one of the founders of integrative medicine, I think puts out a very nice anti inflammatory pyramid. And the other pyramid that I like, I don't know if it's a pyramid, but I am a big fan of Dan Buettner's Blue Zones. I think that people are probably familiar with Blue Zones. Where Dan Buettner studied the centenarians of the world. There were five areas, there's now six. Singapore got added where people tend to live to 100. And studying their diets and behaviors I think has been very informative because we're never going to run a diet study for 100 years, let's face it, right? All these wonderful RCTs are short term. I love the fact that there's now this pattern, this dietary pattern that is associated with good health, good quality of life.
Christopher Gardner
And I would just like to add that we actually did a podcast with Dan Buettner a little while ago which was lots of fun and he explained the Blue zones and what they were doing. He also gave this amazing recipe for a soup in there which I can recommend. So if anyone's interested, they can search just for Blue Zones or Dan Buettner and they will find that episode. So tell me what's on the plate?
Dr. Tomiko Katsumoto
You know, I like the kind of MyPlate. This is sort of the approach where you take a plate and you divide it up and really half of it is fruits, vegetables, you know, good stuff. The whole concept of eating the rainbow, I think really is apropos because these are foods that are high in phytochemicals. A lot of the antioxidants that are super important for calming down our immune system. Cruciferous vegetables. These are things like broccoli and kale and cauliflower and these really kind of the deep leafy greens that I've come to love and embrace. And they're so important. I really think food is medicine and these are incredibly important in terms of helping our liver detoxify. You Know, we're living in a very polluted world, and I think that these are super helpful foods that can help us clear our body of a lot of these toxins, these endocrine disruptors, which we haven't talked about. But there's a lot of these things that we need to be thinking about that are super helpful for my patients. So half of the plate, I think, focusing on high quality vegetables, some fruits, and then a quarter of the plate being proteins, preferably plant proteins or lean proteins, but things like beans and lentils. I'm a big fan of tofu, A lot of. And then whole grains. I think the thing to keep in mind is that, as we know with our ultra processed foods, we tend to eat a lot of these very refined grains. You know, the white rice, white pasta, white bread, these things that have had a lot of the nutrients stripped out of them and a lot of the fiber stripped out. So refined grains is where we want to go. And so really whole wheat and whole, you know, things like quinoa, I love. And some of these ancient grains are also really good, like faro and bulgur and millet, if you kind of imagine, I guess it's really the plate method, the pyramid method is a little more complicated to think through, but those are the key staples that I try to encourage my patients to aim for. Again, animal products in moderation, really limiting them. If you look at the blue zones, they say that the majority of blue zones ended up eating meat less than five times a month. So really that comes down to maybe once a week. Meat should be considered a treat. The other thing I'll mention that I love about the blue zones is that one thing that was commonly shared across all the five blue zones is they all ate a half to one cup of beans a day. Beans or lentils. So these legumes that are so good for us, packed with protein, packed with fiber. Another food type that I love a lot are things like chia seeds and flax seeds. These are. I think chia seeds are the perfect food. They're high in fiber, high in omega 3, high in protein. You know, they've just got so many great components that I add them to my smoothies. I just try to incorporate them wherever I can. I get a big bottle of them and add them wherever I can.
Christopher Gardner
Is there any view around oily fish and arthritis? Because I know that there's a sort of spread of opinion I feel, between the people that I interview, but there seems to be quite a lot of people talking about oily fish. As being beneficial in general. You've been talking about very much plant centric diet. What's the evidence with people with arthritis?
Dr. Tomiko Katsumoto
So fish I think can be a helpful component because of the omega 3s. So we know omega 3 fatty acids are incredibly anti inflammatory. That being said, I also encourage my patients to not go too heavy on fish to eat the smaller fish. So not so much the tuna and the swordfish, things that are much larger and can end up bio accumulating things like heavy metals and toxins, trying to go for the wild caught instead of the farmed. But again I would say what do I do? I end up taking The Vegan Omega 3, which is from algal sources. So algae. I think there are different ways of getting omega 3s. I mentioned Chia seeds also have them and there's different types. So fish I think it can be a good thing but not to overload. And I tend to also recommend I tell my patients check out the Monterey Bay aquarium's resource called seafoodwatch.org Seafood Watch has a lot of the examples where fish what's sustainably caught and which ones are thought to be healthier. We have to be thinking about pollutants. Our oceans are not the cleanest so we have to be thinking about that as well.
Christopher Gardner
That's really interesting. One thing I haven't heard you mention is probiotics, you know, like live bacteria to go and go or prebiotics or fermented food or things like this. Does any of that matter as we're thinking about inflammation and arthritis?
Dr. Tomiko Katsumoto
Absolutely. We don't have data yet specifically on arthritis. But I will say the prebiotics and probiotics are all so critical in maintaining a very healthy gut microbiome. I think the best study on this is called the Fee Phi FO study done by my colleagues Christopher Gardner, Justin Sonnenberg, Erica Sonnenberg where they did a very elegant study using equipoise, meaning they didn't try to game the system in any way. They didn't know they basically put head to headquarters high fiber diet compared to a high probiotic diet using fermented foods as the source of a lot of these bugs. And they ran this study head to head comparison, didn't know which one was gonna end up being more anti inflammatory. And what was so fascinating about this study is it was the probiotic fermented food arm that ended up showing a more substantial anti inflammatory effect. That being said, the devil's in the details. So basically the fiber was super, super important in having an anti inflammatory effect. But that was seen only in the subgroup of patients who already had a very robust, diverse host microbiome. In the patients. Patients, the participants who ended up not having as much gut microbiota diversity, they ate a ton of fiber, and they ended up actually getting more inflammation. So it was really about, I think about it as the soil and the seed, the soil being the fiber that we need to consume. The prebiotics that are feeding our gut bacteria that are helping our gut to maintain the epithelial barrier integrity and then producing that very strong mucus layer that is the important barrier. We need the fiber for those reasons, but we also need the fermented foods that have the bacteria that populate our gut microbiome. And you need both of them together in concert in order to have a very healthy, diverse microbiome that protects us against inflammation.
Christopher Gardner
And one thing I'd like to clarify, because you talked about probiotics and you talked about fermented food, and I think most people, when they think about probiotics, think about, like, a capsule that they can buy, you know, from the store and pop and fermented food. They think, well, that's something that I buy from, you know, like the supermarket, and it's a food. Were you testing both at the same time? What are you.
Dr. Tomiko Katsumoto
So I guess one could argue fermented foods have a lot of these probiotic bacteria in them. And so they actually might. They're very effective as probiotics. I'm referring to those not. And I think capsules are interesting. I'm not sure how effective they are compared to just eating probiotic foods that are full of these good bacteria that end up staying in our gut.
Christopher Gardner
So when you're saying taking probiotics, you're actually meaning, like, eating these fermented foods full of live bacteria.
Dr. Tomiko Katsumoto
Correct.
Christopher Gardner
From like a yogurt to a kimchi.
Dr. Tomiko Katsumoto
Exactly. Sauerkraut, Kefir.
Christopher Gardner
Sauerkraut or whatever. You're not talking about, like, individual capsules. So within this plate and this design, are you recommending people take these probiotic capsules or are you actually saying, no, I'm recommending these fermented foods?
Dr. Tomiko Katsumoto
I think of food as medicine. So I would encourage my patients to incorporate as many of these fermented foods as they're able to, because that really helps. And especially after, let's say, they've taken antibiotics for some sort of infection that can deplete the microbial diversity. So eating the fermented foods provides a lot of the bugs that help to repopulate our gut. Really providing the seeds, you know, as you then chase that with fiber, which is the soil, the prebiotics, I think both are equally important in terms of really creating a good gut microbiome.
Jonathan Wolf
Do you know someone living with arthritis? Why not send them this episode right now, help them understand how to manage their symptoms with the latest advice from a world leading rheumatologist.
Christopher Gardner
I'm sure they'll thank you. We're sitting in California today and I feel like the number one question that we would get from listeners who are in California to this is that all sounds great, but I'm really worried that I'm not going to get enough protein in the plate that you've just described. And I know that protein is really, really important for my health. But you've just taken sort of all of that. You haven't even really pushed meat at all. Aren't you worried that your patients aren't getting enough protein?
Dr. Tomiko Katsumoto
So when we think about protein, you know, not to get too far into the details, I think that the recommended daily allowance is 0.8 grams per kilogram. So let's say for 150 pound sedentary person, it's about 50 something grams of protein, which can easily be achieved with a lot of the plant based foods. When you think about tofu and tempeh and soybeans and all these other beans and lentils and whole grains also have protein. And so I think that people are almost a little overly obsessed with protein. The rda by the way, really is even a high estimate of what we need. It's two standard deviations above the average. So I think what I am focusing is we are very fiber deficient in our diets and that in general the vast majority of us are, we have too much protein in our diets. And I'll just also make the point that protein cannot be stored. So protein can be kind of in the instant, you know, can be converted into glycogen as a source of energy, but the remainder, the excess ends up getting converted into fat. So I feel like all the excess protein we're dumping into our bodies could be actually causing more problems, you know, so we need to be thinking about that. You know, kidney patients, they can't tolerate too much protein either. So I don't have concerns about too little protein in our diets.
Christopher Gardner
You talked a lot about fiber. I just have one specific question about this, which is like how much should someone be looking to eat during the week? Because you talked about the importance of that for feeding the microbiome and Then pulling down this inflammation, what if someone was trying to understand like what should they be trying to achieve and what is, you know, the average, you know, American, since we're sitting here, what's the average American actually eating today?
Dr. Tomiko Katsumoto
So the average American is eating about 15 grams of fiber and the amount we should be Targeting is between 28 to 35 grams of fiber. That being said, there's a tribe in Africa, the Hadza tribe. Dustin Sonnenberg and his group studied this incredible group of folks and they were getting upwards of 100 grams of fiber in their diet.
Jonathan Wolf
100 grams.
Dr. Tomiko Katsumoto
100 grams of fiber.
Christopher Gardner
And the average American is eating 15?
Dr. Tomiko Katsumoto
Yes. And the Hadzas, you know, they had no chronic diseases, no issues with inflammation. Incredibly healthy. So I think that it just goes to show how little fiber we have been eating and how much that's probably impacted our gut health. And so to get that fiber again, fiber is only found in plants.
Christopher Gardner
Final question, because we're over time it's been fascinating. You've laid out a really big overhaul to our diet. And so lots of people listening to that will be saying like, you know, I'm not ready to make like all of those changes. If you were going to say to them like, here's one small change that you can make tomorrow.
Dr. Tomiko Katsumoto
Start small, make swaps that are barely noticeable. So I tend to, you know, like plant based milks, soy milk, oat milk, things like that. Or take a day of the week, do the meatless Monday where meat becomes the condiment and the main highlight are the plants in your meals. This doesn't have to be overnight. And again, I don't think that the goal is that the world is going to turn vegan, but I do feel like we do need to move that direction in terms of really. I mean there's so much evidence supporting plant centric eating patterns that correlates with good health with less inflammation, with a lot of these chronic diseases that are plaguing our society. Not to mention that it is a helpful thing for the planet and a helpful thing for so many other things.
Christopher Gardner
Tomiko, thank you so much. I would like to try and do a quick summary and this is a new topic for me, so please correct if I got anything wrong. So if I think back across it, the thing that's most in my mind is for most of us eating the regular diet, our whole body is on fire with inflammation, which is like this terrifying image of every bit of it burning down. And the issue is like inflammation is like our damaged repair system. So we need to have some. But it's supposed to just come on some of the time. But because of the food that we're eating and the lives that we live.
Jonathan Wolf
It'S sort of like switched on all the time.
Christopher Gardner
And this is your image of it all sort of burning down. Diet is the central issue here that you're saying is causing this inflammation because of the sorts of foods that we eat. But critically also that our microbiome is so damaged compared to the microbiome of our ancestors, and that our ancestors had this much better gut health and that really protected them. Whereas today, because of what we have combined with our food, we're having this, like always on inflammation. And that is not just leading to sort of the arthritis that we spent a lot of time talking about, but actually it's this risk factor for any autoimmune disease, but also cancer and heart disease and all the rest of it. You gave this brilliant story of saying, well, you know, if I ate a big hamburger right now, and then you took my blood, you know, like a few minutes later, you'd actually see in my blood that it just doesn't look like it normally does and it's cloudy, it's full of all this saturated fat, and that that is that this first step leading to inflammation, which is a very, like, scary image. We talked a bit specifically about how this links to arthritis and you said there's sort of two main types of arthritis that list might be living with osteoarthritis, which you said is the most common, which historically we thought of is only wear and tear. But you're saying now you think there is this inflammatory component because you see the impact of food improving it. And then rheumatoid arthritis, which we know is this sort of autoimmune, meaning it's like our own body attacking us. And it's this very direct explanation of how the inflammation is causing this problem. And therefore, if you can reduce the inflammation through food, you ought to really be able to have this direct impact. And you, I think, painted a picture of just how much this impacts your quality of life. And so this is another way in which if you can't keep the inflammation under control, we end up having our quality of life really impacted. Now, all of that was a bit depressing, but then I think you switch to, like, actually really positive news that it is possible, like, within eight weeks of changing your diet to have a profound impact on your arthritis, because it's having this profound impact on inflammation. And then you describe to us, like, let me Describe to you like an anti inflammatory plate, like the plate that you take to your patients in Stanford. And you know what I took away was for your plate, half this plate is vegetable and fruits. You want to eat the rainbow. You particularly like. Certain plants that you felt were particularly good for anti inflammatory properties. Broccoli, kale, cauliflower. This was your cruciferous. Cruciferous. I don't know what else is in cruciferous. I'm going to look that up later. You were selling chia seeds. There's another one that like you really feel like packs all of this in quarter of the plate is protein. But when you talked about protein, you immediately went to like beans, lentils, tofu. So you're talking about plant proteins because they were giving you protein but they were also giving you all of this fiber and more of this anti inflammatory. And then you know, the other quarter being sort of like whole grain. So avoiding all the traditional sort of refined grain. I was brought up with like, you know, you start with potatoes and pieces of bread and here you're talking about whole wheat, but also quinoa. And you mentioned a lot of fun, like ancient grains that I think, you know, were not in my supermarket 20 years ago but are now like farrow and Bulgar and millet. I don't know what millet is, but I'm going to look that one up as well. And then like animal products, you can have animal products but you want this to be in moderation. So rather than like your plate is mainly a piece of meat with a little bit around it. It's like, you know, you can have it from time to time. Oily fish, you know, can be helpful. If you don't want to eat fish at all, then you're talking about supplements that allow you to get those, those Omega 3. But what you're saying is I just want to play this black because it is sort of amazing. You're saying like if you are living with arthritis and you were to make that sort of change in your diet, you think it can really change like not only your symptoms, but even potentially get you to a point where you say, I don't even need to take all the medication I'm taking today.
Dr. Tomiko Katsumoto
Absolutely incredible summary, Jonathan. Thank you so much.
Christopher Gardner
You're very welcome. Thank you.
Jonathan Wolf
Now, if you listen to the show regularly, you already believe that changing how you eat can transform your health. But you can only do so much with general advice from a weekly podcast. If you want to feel much better now and be on the path to live many more healthy years, you need something more. And that's why more than 100,000 members trust Zoe each day to help them make the smartest food choices. Combining our world leading science with your Zoe test results, Zoe is your daily companion to better health for life. So how does it work? Zoe membership starts with at home testing to understand your unique body. Then Zoe's app is your health coach, using weekly check ins and daily guidance to help you shift your food choices to steadily improve your health. I rely on Zoe's advice every day and truly it has transformed how I feel. We give Zoe a try. The first step is easy. Take our free quiz. To find out what Zoe membership could do for you, Simply go to Zoe.com podcast where as a podcast listener, you'll get 10% off. As always, I'm your host, Jonathan Wolf. Zoe Science and Nutrition is produced by Julie Pinero, Sam Durham and Richard Willin. The Zoe Science and Nutrition Podcast is not medical advice and if you have any medical concerns, please consult your doctor.
Christopher Gardner
See you next time.
ZOE Science & Nutrition: How to Reverse Arthritis in 8 Weeks | Dr. Tamiko Katsumoto
Release Date: February 27, 2025
In this compelling episode of ZOE Science & Nutrition, host Jonathan Wolf engages in an enlightening conversation with Dr. Tamiko Katsumoto, a distinguished professor of rheumatology and immunology at Stanford University. The discussion delves into the intricate relationship between diet, inflammation, and arthritis, unveiling groundbreaking research that suggests dietary interventions can reverse arthritis symptoms within eight weeks. Dr. Katsumoto shares her expertise on how food choices impact chronic diseases and offers practical advice for listeners aiming to improve their health through nutrition.
Dr. Katsumoto begins by elucidating the complexity of arthritis, distinguishing between its various forms such as rheumatoid arthritis (RA), osteoarthritis (OA), lupus, and psoriatic arthritis.
Arthritis Explained:
"Our joints are generally protected areas where you've got your bone, you've got a synovial lining... The problem is with inflammation, there can actually be a breach of those protective barriers" ([05:28]).
Inflammation as a Double-Edged Sword:
"Inflammation can be thought of as a damage repair mechanism... The key problem is that... we are being constantly exposed to these various inflammatory threats" ([15:39]).
Dr. Katsumoto emphasizes that chronic inflammation is not limited to the joints but is a systemic issue affecting multiple organs, thereby linking arthritis to other chronic conditions like diabetes, hypertension, and cardiovascular diseases.
The conversation highlights the alarming increase in autoimmune and inflammatory diseases, with Dr. Katsumoto pointing out that genetic factors alone cannot account for this surge.
Increasing Prevalence:
"So it's estimated that about 1 to 2% of our population is affected by rheumatoid arthritis. The numbers for osteoarthritis are much higher in the millions" ([08:40]).
Epigenetics and Environmental Factors:
"We are not evolving that quickly. Our genetics are not changing... environmental drivers that are leading to this increased prevalence of arthritis and other chronic inflammatory diseases" ([10:01]).
This section underscores the importance of environmental and lifestyle factors, particularly diet, in the manifestation of these diseases.
A significant portion of the discussion focuses on how dietary choices influence inflammation and, consequently, arthritis symptoms.
Diet-Induced Inflammation:
"A lot of our dietary components, like sugar, saturated fat, processed foods, drives inflammation in various ways" ([26:05]).
Personal Anecdotes:
Dr. Katsumoto shares insights from her clinical experience, noting that her patients often feel immediate joint pain after consuming trigger foods like sugar or red meat ([31:23]).
She posits that modern Western diets, rich in ultra-processed foods, contribute significantly to chronic inflammation, which exacerbates arthritis and other diseases.
Dr. Katsumoto discusses a pivotal randomized controlled trial named Plants for Joints, conducted by her Dutch colleagues, which examined the impact of a lifestyle intervention on arthritis patients.
Study Design:
"They randomized a group of patients with... one in rheumatoid arthritis and one in osteoarthritis... a metabolic associated osteoarthritis" ([21:10]).
Intervention Details:
"They put them through a lifestyle intervention... focusing on whole food, plant-based diets... minimizing processed foods, minimizing animal products, increasing fiber intake" ([21:11]).
Outcomes:
"At the end of the study, they saw dramatic improvements in the patient's joint disease... Patients in the lifestyle program looked more deeply to see what was most likely driving this difference" ([24:37]).
Notably, the trial revealed that participants not only experienced reduced arthritis symptoms but also some were able to discontinue their medications after a year, highlighting the profound impact of dietary changes.
A central theme of the episode is the connection between gut health and systemic inflammation.
Gut-Joint Axis:
"The gut has the biggest immune system... that can lead to this systemic inflammation" ([34:36]).
Microbiome Diversity:
"Diversity of the microbiome is super important... patients with rheumatoid arthritis... have a decrease in their microbial diversity in their gut" ([35:01]).
Dr. Katsumoto explains that a healthy, diverse gut microbiome can mitigate inflammation, whereas a compromised microbiome fosters chronic inflammatory states. She advocates for diets rich in fiber and fermented foods to nourish the microbiome and maintain gut barrier integrity.
The discussion extends beyond arthritis, exploring how chronic inflammation is a common thread linking various diseases, including cancer and cardiovascular disorders.
Inflammation and Cancer:
"We are learning how important the immune system is in terms of cancer control... diet plays a really important role in the immunotherapy response" ([36:26]).
Dietary Impact on Cancer:
"The WHO has declared that processed meats and red meats are considered carcinogenic... colon cancer rates are going up" ([43:51]).
Dr. Katsumoto highlights recent research indicating that diets high in fiber and promoting microbiome diversity can enhance the effectiveness of cancer immunotherapies, underscoring the pivotal role of nutrition in disease prevention and treatment.
Dr. Katsumoto offers actionable advice for listeners aiming to reduce inflammation and manage arthritis through diet.
Plate Method:
Incorporating Fermented Foods:
"Incorporate as many of these fermented foods as they're able to, because that really helps... providing the seeds" ([54:15]).
Moderation in Animal Products:
"The majority of blue zones ended up eating meat less than five times a month... meat should be considered a treat" ([49:25]).
Fiber Intake:
"The average American is eating about 15 grams of fiber... Target between 28 to 35 grams of fiber... Some, like the Hadza tribe, consume upwards of 100 grams" ([57:27]).
Gradual Changes:
"Start small, make swaps that are barely noticeable... Meatless Mondays... plant-centric eating" ([58:37]).
These recommendations aim to make dietary transitions manageable while maximizing anti-inflammatory benefits.
Dr. Tamiko Katsumoto provides a hopeful outlook, affirming that significant improvements in arthritis symptoms and overall health are achievable through thoughtful dietary changes. By prioritizing whole, plant-based foods, increasing fiber intake, and nurturing the gut microbiome, individuals can combat chronic inflammation and enhance their quality of life. The episode serves as a compelling testament to the power of nutrition as medicine, encouraging listeners to adopt sustainable dietary practices for long-term health benefits.
On the Role of Diet in Chronic Diseases:
"The biggest myth is that there's nothing you can do to change your arthritis course... through diet, lifestyle, etc., that can make a difference." ([03:13]).
On Inflammation as a Systemic Issue:
"Rheumatoid arthritis... this is a systemic inflammatory response. It's not just in our joints, it's our whole body on fire." ([16:00]).
On Clinical Trial Success:
"Patients that underwent this lifestyle program... were able to get off of their medications." ([25:19]).
On Microbiome Diversity:
"Diversity of the microbiome is super important... trying to figure out what are the good bugs." ([35:01]).
On Practical Dietary Swaps:
"Start small, make swaps that are barely noticeable... plant-based milks, soy milk, oat milk." ([58:37]).
This episode of ZOE Science & Nutrition masterfully intertwines scientific research with practical advice, empowering listeners to take control of their health through informed dietary choices. Dr. Katsumoto's insights offer a roadmap for reversing arthritis and mitigating the risks of other chronic diseases, underscoring the profound impact of nutrition on overall well-being.