
You probably already know that your diet can hugely influence how well you feel, but did you know that the food you choose to eat can change the make-up of your entire body, all the way down to the health of your cells?
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Dr. Rangan Chatterjee
I'm really excited to share that I've been selected as one of the very few Apple Podcasts Creators We Love a campaign that celebrates leaders and trailblazers in podcasting. Thank you to everyone who has listened and shared this show with their family and friends over the years and if you have discovered the show for the very first time through the Creators We Love Campaign. Welcome and I hope you enjoy listening Today's Bite Size episode is sponsored by AG1, one of the most nutrient dense whole food supplements that I've come across and I myself have been drinking it regularly for over six years. AG1 makes it simple to be the best version of you over 70 ingredients 1 scoop once a day for less than a cup of coffee. It's a science driven daily health drink which supports your energy, focus and immune it also helps support your gut health. For example, it contains calcium which contributes to the normal function of digestive enzymes and biotin to maintain your own intestinal mucous membrane. Subscribe now and get a free bottle of vitamin D and five free AG1 travel packs with your first subscription. See all details@drink ag1.com LiveMore welcome to feel Better Live More Bite Size, your weekly dose of positivity and optimism to get you ready for the weekend. Today's clip is from episode 485 of the podcast with internationally renowned physician, food scientist and best selling author Dr. William Lee. Now, you probably already know that your diet could hugely influence how well you feel. But did you know that the food you choose to eat can change the makeup of your entire body, all the way down to the health of your cells? In this clip we explore the intricate relationship between what we eat and how our bodies function. Dr. Lee shares how certain foods can stimulate and protect our vital stem cells, which in turn enhances our body's natural ability to regenerate and heal. Over the past few years, there's definitely been more and more conversations about the relationship between food and health. But I think you, Dr. Lee, are talking about a couple of things that I don't see many other people talking about. For example, stem cells. So number one, what are stem cells? And number two, what is the relationship between them and the food that we consume?
Dr. William Lee
It's a great question and it's a really interesting topic. A stem cell is basically a early primitive cell that has formed us. So when your dad's sperm met your mom's egg and we were just this ball of cells, those cells all started as stem cells, which means that they could become anything. Some of them became blood Vessels. Some of them became heart tissue, some of them became a brain, Some of them became nerves and bone. And those primitive cells, by primitive, what it means is that they can become anything. They. Their destiny has not yet been decided. And over time, they can be coaxed to become something that we need. And when we're born and the umbilical cord is cut, we have extra stem cells left over. These extra stem cells, about 70 million of them, are still floating around our blood. And there are instructions at the time of birth to tell these extra floating stem cells, hey, it's time to park your car, hide out in the places that you're going to be for the rest of your life, and you'll come out when you're needed. So we've got extra stem cells so that we never run out. So these 70 million extra cells, stem cells, they are in our bone marrow, and that's mostly stem cells. And. And the stem cells in your bone marrows, they help us create more blood cells that we actually will require over our lives. But they also contain these stem cells that are sticking around and these stem cells and can regenerate us from the inside out. They heal us from the inside out, meaning if we actually have an injury, and this is relatively new research in medicine, if we cut ourselves, let's say you're riding a bike and you fall off, all right, and you scrape your knee on the path, that injury on your knee will send an alert signal like 911. And basically, in response to that distress call, the stem cells come flying out of our bone marrow like bees coming out of a hive, looking for the area that's injured that they need to repair, help to repair from the inside out. And it's not just a scrape of the knee. It could be your heart, your brain, your nerves, could be any organ at all that our stem cells repair. And the remarkable thing is that they can become anything. If you need a liver repaired, they can become liver cells. If you need a nerve repair, they can become nerve cells, blood vessels, they can become vascular cells or blood vessel cells, even brain. We believe that brain tissue can regenerate in part with these stem cells.
Dr. Rangan Chatterjee
Yeah, I mean, that's incredible just to hear that we have this, you know, reserve capacity within the body. So stem cells are clearly very important. Yeah. But I think when we talk about foods, I think people these days are thinking about the relationship between food and obesity, food and type 2 diabetes, food and longevity, and all these kind of things. I don't think many people, at least not to my knowledge, are thinking about the relationship between food and stem cells. So you mentioned what they are. Talk to us about how we can use food or choose certain foods that help us harness the. This potential that we have inside of us.
Dr. William Lee
Yeah, well, so I'm a scientist. I study blood vessels. That's where my, my root as a scientist is, by circulation. And in fact, our blood vessels are remarkable. 60,000 miles worth of blood vessels are packed into our adult bodies. That is so extensive that if we were to pull out all the blood vessels and line them up end to end in your body, you'd actually form a line, a thread that would wrap around the Earth twice. 400 of those miles are actually in our brain. And these literally are the highways and byways of everything. Oxygen we breathe, the nutrients that we eat, they deliver to every single organ in your body. Really, really critical. And in fact, no matter what else you think about in terms of your health, if your blood vessels are healthy, you are at a really great starting point to optimize the rest of your health. But if your blood vessels are unhealthy, you're going to be far behind. In fact, it'll be impossible to optimize your health in any other part of your body. This is especially true as we get older, like 40 and above. We need to start paying super attention to how well our blood vessels are functioning. Now. These roads, these blood vessels need to be maintained just like a road, you know, in the countryside. If you don't maintain the road, it's going to break down over a period of time. And one of the things, as a vascular blood vessel researcher, angiogenesis researcher, we discovered early on is that stem cells in our body contribute to building and repairing blood vessels. So that was sort of how I became interested in and quite familiar and actually worked on stem cell research. In the lab. We actually discovered many chemical substances that can stimulate stem cells to help do their repair. Some of the synthetic chemicals that you could order from a research shop could actually stimulate stem cells. But then it was really jaw dropping to me. In fact, one of the most light bulb going off moments that I had as a food, as medicine researcher to discover that natural substances in our food can similarly activate our stem cells and call them into action. And without necessarily putting out a distress call, we can just gently coax our body's own reserve into action to help repair ourselves in a more robust way.
Dr. Rangan Chatterjee
So which are some of the top foods that we can choose to put inside our mouths that are going to do this?
Dr. William Lee
Yeah. Okay. So first of all, this is, we're at the beginning of, you know, a new era looking at regenerative foods, foods that can stimulate regeneration. So I don't have like the wrapped gift box to give you of a laundry list of all the foods known to man. We're still doing research on this. But I'll tell you, I'll give you some examples because. And when I talk, by the way, Rangan, I really refer to both laboratory, but also to human evidence, which I think is really important. You know, something we see in the lab is interesting and they can actually raise an idea. But at the end of the day, it's whether or not it works in people that makes all the difference in the world. So I'm going to kind of flip back and forth a little bit, but always emphasize what we know in people. So first of all, you might not be surprised that the source of stem cell activating substances are plant based foods. Mother nature sort of medicine cabinet are fruits and vegetables, nuts and legumes and healthy oils and seeds, you know, omega sources of omega 3s. Researchers have been actually mining the same pharmacopoeia farm with an F, not a ph, looking at what substances are in nature that can stimulate stem cells. So I'll give you an example. We know that there's a natural bioactive, a natural chemical found in plants called ursolic acid. Okay, That's U, R, S O L I C or solic acid. It's found in fruit peel, right? The peel of an apple, the peel of a pear, the peel of cranberries, a peel of blueberries. I mean, unless you were a kid and your grandmother peeled the apple for you, you just take an apple and clean it and then just eat the whole thing, right? The peel's got good source of dietary fiber and ursolic acid. Ursolic acid has been shown to stimulate stem cells to come out of the bone marrow and help to stimulate regeneration and to repair blood vessels, for example. Quite amazing. All right, that's an example. There's another substance that has been discovered called beta D glucan. Now this is a soluble fiber which we know is good for gut health and it does a lot of other interesting things too that are beneficial for the body. But beta glucan has been discovered to stimulate stem cells. Now where do you get beta glucan? You can find them in mushrooms, both the cap and the stipe. The stem of the mushroom has beta glucan. In fact, the stem of the mushroom has twice as much beta glucan as the cap of the mushroom oats also has beta D glucan. You know, if you're actually having steel cut oats for breakfast, for example, is another source of beta glucan and barley. Now barley has actually been studied with beta glucan to look at stimulating the stem cells that can regenerate your circulation, that can help to repair and grow new blood vessels where they're needed. And this is exactly in my wheelhouse to study circulation. So we took this even further to look at the role of other foods that can stimulate stem cells. And one of them is dark chocolate. Dark chocolate has a very particular benefit because first of all, chocolate is a confection, it's a candy, it's made, you know, it's crafted to be sweet and delicious and most people like dark chocolate, but it is contains a plant based food ingredient and that's cacao. Cacao comes from a tropical tree where the seed pod of the cacao is shaped like an American football. And that those seeds are the ones that are dried, fermented, ground into a powder and used by percent to actually make chocolate. So if you have a 50% cacao chocolate, it's got half of the cacao. If you've got 80%, it's got a lot more, 90%, etc. Well, what research has been done shown that 80% or higher cacao puts enough of a natural plant based bioactive called pro anthocyanidin into your bloodstream. So this has been measured and in, in the clinic, if you actually give people who have, let's say coronary artery disease, so they've got narrowing of their blood vessels and stiff hard blood vessels, these are not people at their optimal state of health. If you measure their stem cells and then see how many stem cells are floating around their blood, which is not many, and then you were to actually do a simple test called flow mediated dilation FMD to check how resilient their blood vessels are. If you do that at baseline to see how well the blood vessels in these people are doing not that well, then researchers have given them two cups of dark chocolate in the form of hot, hot chocolate. That's it. Two cups to have a day for 30 days. And at the end of 30 days you measure, take out your blood and measure the stem cells again and then do that flow media dilation resiliency test again of the blood vessels to see have they changed. This is what's amazing has been found that dark chocolate, the pro anthocyanins not only got into the bloodstream, but they doubled the number of stem cells circulating in your blood vessels and, and improved by twofold the resiliency of your blood vessels just over the course of a month with as little as 2 cups of hot chocolate. That's dark.
Dr. Rangan Chatterjee
Wow, that's a really interesting point, what you said there at the end there. The quality matters, doesn't it? Because you could get, I guess, a hot chocolate powder from the supermarkets, which was full of additives and full of sugar and has a very low concentration of cacao. Or you could get a completely different one, which is minimal ingredients, high levels of cacao. As you say, 80% plus. That's the nuance, I think, sometimes that we're missing, aren't we, when we talk about food? Hot chocolate is not just hot chocolate. It depends on the quality, right?
Dr. William Lee
That's right. And the stuff that you get is in a packet at the grocery store and it might taste really great. It might be the stuff that we had when we were kids. I know I did. If you now take a look at the ingredient label, I tell people, anytime you're buying anything that's prepackaged, please take a look at the ingredient level before you put it in your grocery cart. Because if you start seeing the added sugar and then the emulsifiers and all the artificial chemicals and preservatives and the stabilizers, that's probably not something that you want to actually put in your body. And if the ingredient label creeps you out, put it back and just look for another choice that, as you say, has minimal numbers of ingredients. Or even better yet, I mean, and I say this to people who are really committed to using a natural way to improve their health. Put it together yourself. I mean, you can even make it without dairy, which is really interesting. You can make yourself a really tasty, super dark chocolate. And in fact, a lot of people don't know this, but the history of cacao and chocolate goes all the way back to the Aztec civilization, where at some point they actually considered chocolate was used as currency. It was so valuable, and at a certain point of time, it was used for its medicinal and ceremonial value. The healthful chocolate we're talking about is really paying attention to the details of the quality of what you're actually going to put into your body, because that's going to influence how your body responds to it.
Dr. Rangan Chatterjee
It's really fascinating. We mentioned a few foods already that can help our stem cells. What about olive oil? Does that have any relationship with our stem cells?
Dr. William Lee
Absolutely. So olive oil is a healthy fat, as they say. It's a plant based food comes from plants, the olives. And it contains bioactives, many bioactives. Some of them have been identified. The ones that actually have been best studied, one of them is called hydroxy tyrosol. The other one's called oleocanthal. And you know, for people who are listening, you know, if you're a science geek, you can write all this stuff down, but just know that there are these natural substances that have powerful effects on our body. And for example, hydroxy tyrosol and as a molecule, but olive oil as a food substance, all right, has been shown to be protective of our stem cells. Meaning when you consume olive oil and you get these polyphenols, the hydroxy tyrosal canthal in our bloodstream, circulating around, look, there's a lot of stuff in our bloodstream that's going on, a lot of exposures that we have. And when you've got hydroxy tyrosol from olive oil in the bloodstream along with your stem cells, they sort of act as police escorts to help your stem cells get to where they go in a safer way. They're escorted to where they're needed, they're protected. And so why do they need to be protected? Well, if you think about it, there's a lot of oxidative stress that can be in our bodies. You know, oxidative stress can come from fumes that you breathe, from vaping, from off gassing, from carpets, from artificial flavorings and preservatives that you have in your food, from cleaning materials that you're actually having. All these chemical exposures cause oxidative stress in our blood, which can damage your stem cells. Hydroxytyrosol, again, is one of those natural molecules that have been shown to protect your stem cells against oxidative stress. I think the quality of the olive oil is really, really important. So extra virgin, first press. Olive oil is always going to be tastier. You're going to get that peppery, sometimes peppery taste to it. By the way, those, that's what the polyphenols are. They're actually giving you that taste sensation, a great taste sensation of olive oil. All right? I always want to get the highest quality olive oil. So what I look for are olive oils that are made with pressed with only one kind of olive. It's called mono varietal olive oil. But I look for mono varietals, olive oils coming from one of three different kinds of olives that you can actually find very easily in the store. And the reason I look for Them is because they have the highest levels of polyphenols of all the olives. All right, so if you like Spanish olive oil. All right, I look for mono varietal Spanish olives made with the variety of olive called picual P I C U a l. Fortunately, it's a very common olive in Spain you can easily find picuol mono variete olive oil. And it's not that expensive. All right, if you like Greek olive oil. I love Greek olive oil. The olives that have highest polyphenols among Greek olives are called koroneki K o r o N E I K I Koroneki olives. Fortunately, a very common olive in Greece, monovarial highest polyphenols taste amazing. If you like Italian olive oils. In Umbria, the highest polyphenols have been found in Moriolo olives. M O R o a I l o Moraiolo olives, which is found in Umbria. It's a less common olive, it's going to be more expensive. But again, tastes great. Highest polyphenols. And so I kind of tell people, look, if you're going to go buy olive oils, why not get the highest quality? It's fuel. You want to be able to have it taste great. If you're going to use it and dip some bread or whatever it is, sourdough bread or whatever, something healthy in it, why not get the best? And why not get the best with the not only best taste, but also pure and also with the highest polyphenols. And that's how I actually choose.
Dr. Rangan Chatterjee
Super interesting. Any other foods that we forget about when thinking about our blood vessels that you would like to highlight and encourage us to bring into our diets?
Dr. William Lee
Yeah, well, you know, it turns out that two beverages, tea and coffee, have polyphenols that are heart healthy and beneficial. All right, Tea has catechins and the specific catechin that has been best studied is called EGCG, epigallocatechin3gallate. And again, I encourage people not to get hung up on the technical stuff unless you're a science geek, but just know that we know these things. In coffee, there's many different polyphenols. One of the best studies called chlorogenic acid. And both of these are heart healthy and vascular healthy blood vessel healthy for similar reasons. They protect your blood vessels against oxidative stress, they lower inflammation, they're good for gut health. So they're powerful levers that can actually help us. And if you, by the way, if you combine this over the course of the day with eating some leafy greens. And then you have some of these blood vessel regenerative foods like the barley with the beta glucan or the mushrooms that we talked about earlier, or a little bit of dark chocolate, high quality dark chocolate. You see, it's the net consumption of the things that we're eating all day long that expose our blood vessel, that extraordinary network to help us maintain the roads in our body and that's our circulation. And I think that all this discussion about longevity accompanying this quest to live long, we want to live well. And the choices that you're making now, the research is finding remarkably, that we can actually improve our future, us as well in ways that are profoundly important. Our vision, our brain, our muscle strength, our ability to enjoy life. We want to actually really enjoy every year that we get. And I think that the good choices, those little tiny little tweaks we make, they can make a big difference.
Dr. Rangan Chatterjee
Hope you enjoyed that Bite Sized clip. Do spread the love by sharing this episode with your friends and family. And if you want more, why not go back and listen to the original full conversation with my guest. If you enjoyed this episode, I think you will really enjoy my Bite Sized Friday email. It's called the Friday five and each week I share things that I do not share on social media. It contains five shorts, short doses of positivity, articles or books that I'm reading, quotes that I'm thinking about, exciting research I've come across, and so much more. I really think you're gonna love it. The goal is for it to be a small yet powerful dose of feel good. To get you ready for the weekend, you can sign up for it free of charge@drchatterjee.com Friday 5. Hope you have a wonderful weekend. Make sure you have pressed subscribe and I'll be back next week with my long form conversational Wednesday and the latest episode of Bite Science next Friday.
Podcast Summary: Feel Better, Live More with Dr Rangan Chatterjee
Episode: BITESIZE | 5 Food Tips to Heal Your Body, Boost Your Brain Health & Live Longer | Dr William Li #562
Release Date: June 5, 2025
In this episode of Feel Better, Live More, host Dr. Rangan Chatterjee engages in an enlightening conversation with esteemed physician, food scientist, and best-selling author Dr. William Li. The discussion delves into the profound impact of specific foods on our body's regenerative capabilities, particularly focusing on stem cells and vascular health. This summary encapsulates the key points, insights, and conclusions drawn from their dialogue.
Timestamp: [02:56]
Dr. William Li begins by elucidating the fundamental concept of stem cells, describing them as "early primitive cells that have formed us" from the moment of conception. These cells possess the remarkable ability to differentiate into various cell types, such as blood vessels, heart tissue, brain cells, nerves, and bones. Dr. Li emphasizes their vital role in the body's regenerative processes:
“Stem cells... can become anything. Their destiny has not yet been decided... They heal us from the inside out.” ([02:56])
He explains that upon birth, approximately 70 million extra stem cells remain in our bone marrow, ready to respond to injuries by repairing tissues and organs. This innate regenerative capacity underscores the importance of maintaining stem cell health through lifestyle choices, particularly diet.
Timestamp: [05:39]
Dr. Chatterjee acknowledges the common discourse surrounding diet and health, noting that the conversation about food influencing stem cells is relatively novel. He prompts Dr. Li to explore how dietary choices can harness the body's regenerative potential.
Dr. Li responds by highlighting that plant-based foods are a primary source of stem cell-activating substances. He introduces the concept of regenerative foods—foods that stimulate the body's natural repair mechanisms without triggering a distress response. This approach promotes robust and sustained healing.
“Natural substances in our food can similarly activate our stem cells and call them into action.” ([08:56])
Timestamp: [09:04]
Dr. Li outlines several key foods and their specific compounds that aid in stem cell activation and vascular health:
Ursolic Acid:
Beta D Glucan:
Dark Chocolate:
Olive Oil:
Tea and Coffee:
Timestamp: [14:53]
Dr. Chatterjee and Dr. Li stress the importance of food quality in maximizing health benefits. Using dark chocolate as an example, they differentiate between commercially available products laden with sugars and additives versus high-quality, pure dark chocolate with high cacao content.
“Hot chocolate is not just hot chocolate. It depends on the quality... high levels of cacao.” ([14:53])
Dr. Li advises consumers to scrutinize ingredient labels, opting for products with minimal additives and higher concentrations of beneficial compounds. He encourages making foods at home to ensure purity and potency, citing the historical medicinal value of cacao in Aztec civilization.
Timestamp: [17:09]
Focusing on vascular health, Dr. Li explains that maintaining healthy blood vessels is foundational to overall well-being. He compares blood vessels to an intricate network of highways that deliver essential nutrients and oxygen throughout the body. Unhealthy blood vessels can impede this delivery system, adversely affecting organ function and overall health.
“If your blood vessels are healthy, you are at a really great starting point to optimize the rest of your health.” ([07:15])
By incorporating the aforementioned regenerative foods, individuals can support their blood vessels, enhance circulation, and promote longevity. Dr. Li emphasizes that these dietary choices not only contribute to physical health but also improve cognitive functions, muscle strength, and overall quality of life.
Timestamp: [21:26]
As the conversation draws to a close, Dr. Li reiterates the cumulative impact of small dietary tweaks on long-term health. He encourages listeners to integrate a variety of regenerative foods into their daily routines to harness the body's innate healing capabilities.
“The choices that you're making now... can actually improve our future, us as well in ways that are profoundly important.” ([21:17])
Dr. Li underscores that holistic and consistent dietary practices are key to leveraging the full potential of stem cells and vascular health, ultimately leading to a healthier, longer, and more fulfilling life.
This episode provides a compelling exploration of the intricate relationship between diet and the body's regenerative processes. Dr. Rangan Chatterjee and Dr. William Li illuminate how specific foods can activate stem cells, support vascular health, and contribute to overall longevity. By prioritizing high-quality, plant-based foods rich in bioactive compounds, listeners are empowered to make informed dietary choices that foster healing from within and enhance their quality of life.
Additional Resources: