Pod Insights The Diary Of A CEO with Steven Bartlett Moment 167: 6 Foods You MUST Eat To HEAL Your GUT!: Dr Will Bulsiewicz About this episode In this moment, the world-renowned gut-health expert Dr Will Bulsiewicz discusses the relationship between your gut health and overall well-being, including your mental and physical health. According to Dr Will, our gut is like a muscle that we can strengthen by eating a range of diverse superfoods such as leafy vegetables, legumes, and fruit. These high-fibre foods can supercharge your immune system by boosting the production of short-chain fatty acids, lower your cholesterol levels, and stabilise your bowel movements. The benefits of creating a diverse gut microbiome aren't exclusive to you, but in fact, your microbes are later inherited by your children, influencing their future health.
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Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:03 Steven Bartlett? You've repeatedly talked about fibre and this thing you called short-chain fatty acids. In your book, you said you believe that they're the most healing nutrient in all nature.
0:12 Dr. Will Bulsiewicz? I think that's actually true, and I also would characterize them as the most anti-inflammatory molecule that I've ever come across.
0:20 Steven Bartlett? And am I right in thinking, we eat fibre, the bacteria in our microbiome breaks down that fibre and it produces this thing, these short-chain fatty acids?
0:30 Dr. Will Bulsiewicz? Right.
0:30 Steven Bartlett? Is that it? That's, that's...
0:32 Dr. Will Bulsiewicz? The story's just getting started, though.
0:34 Steven Bartlett? Okay.
0:35 Dr. Will Bulsiewicz? Yeah, the story's just getting started because the issue is that, that's the simple part, right? These magicians that live inside of us release these short-chain fatty acids for us.
0:43 Steven Bartlett? By eating fibre?
0:44 Dr. Will Bulsiewicz? By eating fibre, or resistant starches.
0:46 Steven Bartlett? Okay.
0:47 Dr. Will Bulsiewicz? But then, then those short-chain fatty acids go to work and our, our immune cells, our human cells have receptors to receive these short-chain fatty acids and act upon the information that they receive. So you could think of them as like a signaling molecule in the sense that your gut microbiome is now talking to your body and telling your body what it wants your body to do.
1:11 Steven Bartlett? So it's training it?
1:12 Dr. Will Bulsiewicz? Yeah, but it has the ability to like flip genes off and on.
1:17 Steven Bartlett? Okay.
1:18 Dr. Will Bulsiewicz? It has the ability to turn down your immune system. So as an example, when I think about autoimmune conditions, if we were to get like super into the details of autoimmune conditions, what you would discover is that we need more short-chain fatty acids to empower these specific cells called T regulatory cells, and those T regulatory cells would actually turn down our immune system and protect us. So, and it's not to say that autoimmune diseases are exclusively the result of a fibre deficiency.
1:47 Dr. Will Bulsiewicz? There is certainly a genetic component, but there was a genetic component 200 years ago, 300 years ago, and yet those, these conditions really weren't that much of a problem back then. So many of these conditions didn't have a name until the last 100 years. And, and the emergence of them, many of them have increased 500% in the last 50 years. Why would that be? It clearly is not genetics. So it has to be related to our diet and lifestyle. And ultimately, when we talk about our diet and lifestyle, we're talking about our microbiome.
2:18 Steven Bartlett? And really, the one of the most important places to start, as you say, is with the fibre.
2:22 Dr. Will Bulsiewicz? I think so.
2:23 Steven Bartlett? You said earlier on, we have to start slow and low with fibre.
2:26 Dr. Will Bulsiewicz? Yeah.
2:27 Steven Bartlett? And that's because we've got to build up those microbes that respond to the fibre and turn it into the short chain fatty acids, right?
2:34 Dr. Will Bulsiewicz? Your gut is like a muscle, right? Like, this is, this is the way that I want people to understand this. Your gut is like a muscle. And a muscle is capable of work, but it has limitations. And the more that the muscle has been trained, the more capable of work it is. So if you lift weights, you might start at fifty kilos. If we're doing a bench press, you might start at fifty kilos. And then you go to fifty five kilos. And then the sixty kilos, and you work your way up. And that's the process of growing strong. And your gut works the exact same way. So if you expose your gut to food, specifically a diverse mix of different foods,
3:19 Dr. Will Bulsiewicz? you are training your gut. And your gut will become more capable of consuming those foods over time. And then you can eventually get to a point where you don't have to then restrict based upon your capabilities, because the capabilities are limitless. Now you can eat whatever you want.
3:37 Steven Bartlett? And is all fibre the same?
3:39 Dr. Will Bulsiewicz? No, not all fibre is the same. Fibre is a very generic word. Fibre is like the word protein. No one would claim that the protein in a fish is the same as a protein in a bean. Yet both of them contain protein.
3:50 Dr. Will Bulsiewicz? Fibre is unique to individual plants. There are many, many different forms of fibre, to the point that we don't even know how many exist. So what we know is this, it's rather simple, though, right? Given that, despite that complexity, it's rather simple. All plants contain fibre.
4:07 Dr. Will Bulsiewicz? Every single plant has unique forms of fibre. We do split it into two major types. These are, again, umbrella terms. These are big labels.
4:18 Dr. Will Bulsiewicz? Soluble and insoluble fiber. The soluble fiber is the kind that dissolves in a drink. It disappears, you don't even know that it's there. Yet typically, the soluble fiber is feeding the microbes. That's the prebiotic fiber. In soluble fiber is the kind that's the grit. So like if you were to add it to a drink, it's not dissolving. It's going to be there no matter what. You could boil the drink, there'd still be fiber in it. So insoluble fiber, most of the time, is not the prebiotic fiber, but it does still serve a purpose. It helps in terms of your bowel transit, which affects your gut microbes. It helps in terms of your bowel movements, which affects your gut microbes. It helps in terms of other things, such as your cholesterol and your blood fat control.
5:03 Dr. Will Bulsiewicz? So both types of fiber, both soluble and insoluble, have advantages. You don't need to worry about those individually. You just need to know that plants have fiber. Every single plant has a unique form of fiber, and every single plant will feed unique families of microbes as a result of this.
5:20 Steven Bartlett? You have these F-goals you talk about in the book when you're recommending diets that you think people should consider. And I think it's important because this word diet is quite stigmatized, right? And it can lead to like disordered eating and things like that. So I think it's important for us to talk about that a little bit, but I do want to know what these F-goals are. And when you use the word diet, you're not saying something that's unsustainable in short, in order to have a short term.
5:42 Dr. Will Bulsiewicz? I'm saying actually the opposite. Like I want people to have abundance. In fact, I would, if you were to ask me, what is the biggest misconception that exists in the gut health space? My answer to that question would be that people are very quick to restrict and less quick to add back. So with regard to F-goals, this is my general framework. It is not the only thing, but this is my general framework for how I remember to organize my day in terms of foods that I'm trying to seek out. Each letter represents different categories of food. So F, fruit. I think fruit has been inappropriately villainized. I think fruit's amazingly good for us. In fact, people that consume more fruit are less likely to have diabetes.
6:26 Dr. Will Bulsiewicz? They also lose weight. Fermented. We've talked about fermented. You can add more diversity to your microbiome by adding fermented food. We need this. G, G stands for greens. Greens have almost no calories, yet tons of nutrition. That's good. And grains. By grains, I don't mean refined grains. I mean unrefined grains. So like whole grains. So good for us. Those are gut microbiome foods, high in fiber and resistant starches. O stands for omega-3 super seeds. So that's chia flax, hemp, and also walnuts. Those contain omega-3 fats. Those are healthy fats that we need more of. A stands for aromatics.
7:08 Dr. Will Bulsiewicz? So that's onions, garlic, shallots. They're delicious. They're also great for your heart and protect you from cancer. L is legumes. So legumes includes beans, peas, and lentils. I would go back to saying like, to me, this is the number one. The number one superfood. Because they're gut health foods and they're longevity foods. And if we look at the evidence with heart disease, cancer, stroke, diabetes, all across the board, you're going to see these reduce your likelihood of having those diseases. S, when I got to S, I kind of lost my mind. Because I felt like I have more that I want to say, so let me just pack it all in.
7:51 Dr. Will Bulsiewicz? So S stands for shrooms, meaning mushrooms. Mushrooms technically are not plants. They're fungi. But they contain fiber and are incredibly good for us. So they are honorary plants. S also stands for seaweed. So most cultures don't consume seaweed, but like, for example, in Japan, they do. And they're incredibly healthy as a result of this. It's another source of unique types of plants with unique sources of fiber. And the last is, I'm going to, in the book, I said sulforaphane, which refers to a cancer-fighting chemical that you will find in broccoli sprouts. But I want to rephrase this to say sprouts. So sprouts to me are superfoods. There's something magical that happens.
8:34 Dr. Will Bulsiewicz? What is a sprout, by the way, for people who are wondering? You could take any, any seed. And if you quite simply add water, you will unlock nature. Because basically that seed is waiting to germinate and grow. So when you enter this code of basically like unlocking it with water, it comes to life. It opens up and out shoots this plant. And that, that plant is the sprout. And the sprout is tremendously high in fiber, protein, but also phytochemicals. There's unique chemicals that you will find in these plants in a disproportionate level compared to, for example, you know, I mentioned broccoli sprouts.
9:19 Dr. Will Bulsiewicz? Broccoli sprouts have 50 to 100 times more cancer fighting chemical than adult broccoli has. So eating a pinch of broccoli sprouts can have, can provide just as much benefit as eating a head of broccoli.
9:36 Steven Bartlett? So interesting. So if you're a parent and you follow the F goals diet that you lay out in your book, the interesting thing I found is if you're a mother and you're having a child, you're then going to pass on some of your microbiome to that child. And also I was reading about that mice study conducted that shows how the Western diet induces a loss of microbial diversity that can compound over a series of generations.
9:59 Dr. Will Bulsiewicz? Yeah, that was a Justin Sonnenberg study. So Justin Sonnenberg is the guy that I'm a big fan of. He's out in Stanford and he actually wrote a blurb on my first book, Fiber Filled. And so the issue is that we want to understand microbial loss that can occur over generations because clearly our generation is different than our grandparents. And it's hard to do with humans because it takes us like, you know, these days 30 or more years to create a new generation. So, but with mice, you can do this very quickly. So he basically started off with mice with a certain level of microbial diversity. The diversity of the microbiome is a measure of the health of their microbiome.
10:42 Dr. Will Bulsiewicz? And then he saw what happened with a low fiber diet. And so basically what he saw is that if you put them on a low fiber diet, that mouse will start to lose diversity. And then it will transfer that on to its offspring. And then that offspring, who's still on a low fiber diet, continues to lose diversity and transfer that on to their offspring, and so on. And what he found was that if during this process, you intervene and you add back the fiber, you can actually restore, on some level, the diversity within the microbiome. You can wake them back up, they can come back. But the issue is, you won't get all the way back to the starting point. So there is a certain level of loss that has taken place as a result of those choices that were occurring over generations.
11:25 Steven Bartlett? If your grandmother has 1,200 species of microbes in her gut as a child, but by the time your mother was born, she had 900, that's what your mother got.
11:35 Dr. Will Bulsiewicz? Yep.
11:35 Steven Bartlett? Then if your mother loses 300 species in her microbiome, now you start off with 600, half of what your grandmother originally had.
11:43 Dr. Will Bulsiewicz? Right. And at some point, the loss of those species becomes problematic, because each of those species is there with a purpose. We evolved to have them, and when they're absent, they're not able to do their job. And the other microbes may not be able to step up to actually do what's the job of what's missing.
12:01 Steven Bartlett? It's just such a great case that, you know, keeping ourselves healthy is keeping our children healthy as well, in many respects. And we also live with our children, so we're creating an ecosystem in our homes of these microbes on everything.
12:14 Dr. Will Bulsiewicz? I think that's completely true, and I also think that like, when we think about generational issues that exist, so, you know, in many studies, they'll say, if your parents had this, then you're at risk for this. And we have assumed that these are genetic things. Yet, much of the genetic research, much of which has been done by Tim Spector, my partner and Zoe, much of that has not played out to prove that it is in fact genetic. I think what's happening is not just the transfer of microbes, I think it's also the transfer of lifestyle.
12:53 Dr. Will Bulsiewicz? And the lifestyle that gets transferred by generation is, if it's unhealthy, then unfortunately, you're transferring along the problems that come with that.
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