ZOE Science & Nutrition - Recap: How to lower your risk of arthritis | Dr Tamiko Katsumoto

Episode Date: February 10, 2026

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 Have feedback or a topic you'd like us to cover? Let us know here Listen to the full episode here

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 Katsimoto to explore how simple changes to what's on our plate can help protect our joints. 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 inflammation, which I know is a lot about what you study? 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, psoriotic 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 a connection with the gut and mucosal barriers that play into the inflammation leading to arthritis. And Tamiko, I know nothing about how my joints work.

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 analogies of what you described? Could you just help me to understand a bit? 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 many years of research is that

these mucosal breaches, for example, in our gut, even in our mouth or our own, 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 and our mouth can end up actually getting confused in 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. 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. Exactly. I don't know if I'm stretching this analogy way too far. 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. 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. 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 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 amulsifiers 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.

So tell me what's on the plate. 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, 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. 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, you know,

things like beans and lentils. 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 kinoa, I love. And some of these ancient grains are also really good, like faro and bulgar 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 are 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, you know, bottle of them and add them wherever I can. 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 has been beneficial. In general, you've been talking about very much plant-centric diet. What's the evidence with people with arthritis? So fish, I think, can be a helpful component because of the omega-3. 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, you know, things that are much larger and can end up bio-accumulating things like heavy metals and toxins, trying to go for the wild-cut 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, you know, check out the Monterey Bay Aquarium's resource called seafoodwatch.org. Seafood Watch has a lot of the examples where fish, you know, what's sustainably caught and which ones are thought to be healthier. You know, we have to be thinking about pollutants. Our oceans are not the cleanest. So we have to be thinking about that as well. I'll end this episode with something I think you'll like, a free Zoe gut health guide. If you're a regular listener, you know just how important it is to take care of your gut. Your gut microbiome is the gateway to better health, better sleep, energy and mood. The list just goes on. But many of us aren't sure how to best support our gut. I wasn't sure before doing Zoe, which is why we've developed an easy-to-follow gut health guide.

It's completely free and offers fun. five simple steps to improve your gut health. You'll get tips from Professor Tim Specter, Zoe's scientific co-founder and one of the world's most cited scientists, plus recipes and shopping lists straight to your inbox. We'll also send you ongoing gut health and nutrition insights, including how Zoe can help. To get your free Zoe gut health guide, head on over to zoe.com slash gut guide. Thanks for tuning in and see you next time.