In short
How diet may lower arthritis risk and symptoms by reducing inflammation, improving gut barrier health, and influencing immune activity.
Guest
Dr Tamiko Katsumoto, professor of immunology and rheumatology at Stanford; rheumatologist who treats rheumatoid arthritis, lupus, vasculitis, and psoriatic arthritis.
Key claims
Arthritis involves inflammation that can breach the synovial joint lining; immune T cells may attack joint proteins after mucosal/gut barrier disruption (“leaky” barrier). Diet-driven changes to the gut microbiome (from sugar, saturated fat, processed foods, emulsifiers, food colors) can increase systemic inflammation and dysbiosis.
Notable examples
gout from uric acid crystals triggering joint inflammation; “plate method” (half fruits/vegetables, quarter proteins like beans/lentils/tofu, whole grains); blue zones (meat <5 times/month, beans 0.5–1 cup/day); omega-3 sources (small wild fish, or algal vegan omega-3; chia/flax); seafoodwatch.org for fish choices.
Written by AI. May contain mistakes. Listen to the episode to check what was said.
Chapters
Tap a time to open that second in VOUnderstanding Arthritis and Inflammation
0:45 to 2:13
Exploration of how arthritis affects quality of life and the role of inflammation.
“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.”
The Immune System's Role
2:13 to 4:21
Discussion on how the immune system can attack joints and cause arthritis.
“And Tomiko, I know nothing about how my joints work.”
Dietary Influences on Arthritis
4:21 to 6:15
Insights into how diet can contribute to inflammation and arthritis symptoms.
“I don't know if I'm stretching this analogy way too far.”
Building a Healthy Plate
6:15 to 8:31
Advice on what to include in a diet to reduce arthritis risk and promote health.
“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.”
The Role of Fish in Diet
8:31 to 10:36
Discussion on the benefits and precautions of including fish in an arthritis-friendly diet.
“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.”
Transcript
Automatic transcript. May contain errors.0:00Dr. Tamiko Katsumoto:Hello and welcome to Zoe Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today, we're talking about arthritis. It might not sound as serious as cancer or heart disease, but arthritis can have a huge impact on your quality of life, turning simple movements into painful tasks. But here's the good news. Emerging research suggests that diet can have a huge impact on the symptoms of arthritis, helping to lower inflammation and even reduce the risk of the disease developing. I'm joined by Dr. Tomiko Katsumoto to explore how simple changes to what's on our plate can help protect our joints.
0:45Dr. Tamiko Katsumoto:It's been eight years since I co-founded Zoe, 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 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 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.
1:22Dr. Tamiko Katsumoto:So it's amazing how much I think my understanding has changed. What is arthritis and how does that relate to this concept of inflammation, which I know is a lot about what you study?
1:35Zoe Hargreaves: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 you can end up getting inflammation. There's actually connection with the gut and mucosal barriers that play into the inflammation leading to arthritis.
2:20Dr. Tamiko Katsumoto:And Tomiko, 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?
2:37Zoe Hargreaves: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. But 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.
3:11Zoe Hargreaves: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 many years of research is that these mucosal breaches, for example, in our gut, even in our mouth, our 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 how our immune system can be connected to joint inflammation.
3:53Dr. Tamiko Katsumoto: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 parts of these joints and breaking that Teflon and then suddenly it's both painful and does not move as smoothly.
4:21Zoe Hargreaves:Exactly.
4:21Dr. Tamiko Katsumoto:I don't know if I'm stretching this analogy way too far. Yes.
4:24Zoe Hargreaves: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.
5:04Dr. Tamiko Katsumoto:Can you help us to understand how this change in what you're eating could suddenly stop your joints been inflamed and in pain because, you know, the link is not obvious?
5:18Zoe Hargreaves: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 affects our gut microbiome. I think that 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. 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.
6:15Dr. Tamiko Katsumoto:So tell me what's on the plate.
6:18Zoe Hargreaves:You know, I like the kind of my plate. This is sort of the approach where you take a plate and you divide it up and really half of it is fruits, vegetables, 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.
7:00Zoe Hargreaves: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, you know, vegetables, some fruits, and then a quarter of the plate being proteins, preferably plant proteins or lean proteins, but, you know, things like beans and lentils.
7:38Zoe Hargreaves:I'm a big fan of tofu, you know, 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 farro and bulgur and millet. If you kind of imagine, I guess it's really the plate method, the pyramid method is a little more, you know, more complicated to think through.
8:21Zoe Hargreaves: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.
9:01Zoe Hargreaves: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, you know, bottle of them and add them wherever I can.
9:23Dr. Tamiko Katsumoto: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?
9:46Zoe Hargreaves: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 bioaccumulating 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.
10:31Zoe Hargreaves: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.
10:59Dr. Tamiko Katsumoto:As you can imagine, hosting this podcast, running Zoe, juggling family life, it all keeps me pretty busy. So I try as best I can to stay energized and show up well in all those parts of my life by fueling my body with the right food, by exercising, and by adding a scoop of Daily 30 to my meals every day. If you haven't heard of Daily 30 yet, it's the gut supplement designed by our gut health scientists here at Zoe. It's made of over 30 high-quality, hand-picked plants, including seaweed, fungi, and different types of fiber. Better yet, it contains ingredients that support gut health, digestion, and energy, which is ideal for packed calendars and busy lives.
11:42Dr. Tamiko Katsumoto:Simply add one scoop a day to any meal for an extra boost of fiber and plant diversity. And because it tastes delicious on just about anything and adds a satisfying crunch, it quite quickly slots into your life, becoming a daily healthy habit you'll always have time for. By the way, whenever we talk about Daily 30 as a good source of fiber, we're required to say that it contains four grams of total fat per serving. Obviously, that's all amazing healthy fats from plants. So order yours today at zoe.com slash daily 30. Thanks for listening and see you next time.
12:22Bye.
From the publisher
Today, we’re talking about arthritis.
It might not sound as alarming as cancer or heart disease, but arthritis can quietly turn simple movements into painful tasks.
Here’s the good news. Emerging research suggests that diet can be a powerful first line of defence - helping to lower inflammation and reduce the risk of the disease developing.
I’m joined by Dr. Tamiko Katsumoto to explore how simple changes to what’s on our plate can help protect our joints.
🌱 Try our new plant based wholefood supplement - Daily30+
*Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system
📚Books by our ZOE Scientists
The Food For Life Cookbook
Every Body Should Know This by Dr Federica Amati
Food For Life by Prof. Tim Spector
Ferment by Prof. Tim Spector
Free resources from ZOE
How to eat in 2026 - Discover ZOE’s 8 nutrition principles for long-term health
Live Healthier: Top 10 Tips From ZOE Science & Nutrition
Gut Guide - For a Healthier Microbiome in Weeks
Better Breakfast Guide
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