
Introducing The truth behind memory loss - and how to stop it with exercise | Dr. Wendy Suzuki from ZOE Science & Nutrition. Follow the show: ZOE Science & Nutrition We spend so much time focusing on how exercise changes our bodies - burning calories, building muscle, shedding fat. What if the most important transformation is happening where you can’t see it? Hidden inside your skull, your brain is changing with every step, squat, and sprint. Neuroscientist Dr. Wendy Suzuki has spent years uncovering how movement rewires the brain. As a professor at NYU and an expert in neuroplasticity, Wendy’s research reveals how aerobic exercise boosts memory, sharpens focus, and even builds a protective barrier against dementia. In this episode, Wendy explains what happens inside your brain when you move, why it’s never too late to strengthen your mind, and the powerful ways exercise can slow brain aging. You’ll discover simple, science-backed habits - including her own brain-boosting routine -...
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Jonathan Wolf
Welcome to Zoe Science and Nutrition, where world leading scientists explain how their research can improve your health.
Dr. Wendy Suzuki
Many exercise routines focus on how we can change the way we look. From increasing the size of our muscles to decreasing the size of our waistline. After numerous sweaty sessions, we can look in the mirror and smile at the progress we've made. But are we neglecting the most important part of our body, the one we can't see in the mirror? That organ hidden in our skull? Just like your muscles, you can change the shape of your brain, but unlike your muscles, you can't flex and feel if your brain is in good shape. Unfortunately, many people only find out their brain isn't as healthy as they thought after it's too late. After a dementia diagnosis, options become limited. Dr. Wendy Suzuki conducts groundbreaking research on how to supercharge the brain. Wendy is a professor of neuroscience at New York University and the author of the book Healthy Brain, Happy Life. Her work outlines how we can not only stave off dementia, but also boost intelligence and improve our mental health. By applying the lessons from this episode, you'll strengthen your brain and stay mentally sharp for years to come.
Jonathan Wolf
Wendy, thank you for joining me today.
Wendy
Thank you for having me.
Jonathan Wolf
Oh, it's a great pleasure. I'm very excited about this topic. Now we have a tradition here at Zoe where we always start with a quick fire round of questions from our listeners.
Wendy
Okay.
Jonathan Wolf
It's designed to be really hard for professors and that's because we have these very strict rules.
Wendy
Okay.
Jonathan Wolf
You can say yes, oh, or no, or if you have to, you can give us a one sentence answer. But it's a bit of a fail.
Wendy
Okay.
Jonathan Wolf
Are you willing to give it a go?
Wendy
Absolutely. Hit me.
Jonathan Wolf
All right. As we get older, do our brains shrink?
Wendy
No.
Jonathan Wolf
Is it possible to grow my brain as an adult?
Wendy
Yes.
Jonathan Wolf
Are there types of exercise that can make you smarter?
Wendy
Yes.
Jonathan Wolf
Is my risk of dementia fixed once I'm an adult?
Wendy
No.
Jonathan Wolf
Can I reduce my risk of dementia just by walking more?
Wendy
Yes.
Jonathan Wolf
I got one more, but you get a whole sentence for this one. What is the most surprising thing you've discovered about our brains?
Wendy
That moving your body is the most transformative thing that anybody can do for their brain health right in this moment.
Jonathan Wolf
I'm really looking forward to this, and that's because I know that a significant part of your career has been dedicated to studying sort of how the brain forms and retains long term memory.
Wendy
Yes.
Jonathan Wolf
And I'm sure that everyone listening to this probably has a memory that holds special significance to them. And I was thinking about that just this morning, about like, what do I recall in particularly vivid detail? And I suspect it's the answer that lots of people say, which is like the birth of my two children. You know, like, I feel like I can remember the sights and sort of the emotions of that time sort of really etched into my brain and I've already forgotten what I had for breakfast. How is it possible that like these two memories of this thing that happened, you know, many years ago are created and somehow stored in my brain?
Wendy
I love that you start with that particular example, because I often use that example when I challenge people to think about that memory that they have that only lasted a moment, but they still have it after years and years. You know, the moment that you hold your firstborn in your arms, yet so many of us can't remember what we had for breakfast this morning. So here's what makes memories stick, including that memory of your two children being born. Emotional resonance is so powerful in allowing things that happen in your life to stick in your memories. We remember the happiest and the saddest moments of our lives. And that is because right in front of our memory structure that is allowing you to remember that memory of the birth of your two children is another almond shaped structure called the amygdala. The amygdala has so many close connections with the hippocampus, that structure critical for forming memories of events like birth of children. But it's the amygdala that infuses that emotional resonance that when really, really amazing things and really, really sad things happen, it helps those memories stick. But that's not the only thing that helps memories stick. Repetition. So you don't have children, you don't hold new children in your arms every single day. But that also helps things stick. That's a bread and butter kind of thing. Everybody remembers association, so we remember things better if they're associated with other things that are already in our long term memory. And that just has to do with how the hippocampus, which is really an associative structure, it sticks things together in memories that happen at the same time. It is that thing that helps us remember the who, what, where, when and how of a particular episode. And that is how it kind of glues our perceptions together. And novelty novel things. Our first child, never been through this before, that also helps things stick. So breakfast, by contrast, not so emotionally resonant. You might have had the same thing or different things. It doesn't hit those marks. But birth of your children, your first kiss, all These other things that we have such deep memories of, that hits all those marks of what makes memory stick.
Jonathan Wolf
So are there different types of memory, or are they all the same? And it's just that some of them, like, fall away.
Wendy
Yes. There are many, many different kinds of memories and different brain structures that are responsible for different kinds of memories. So we've been talking about episodic memories, the memories for the facts and events in. In our lives. That's what most of us think about when we think about the memories of our lives. That is dependent on the structure of the hippocampus. You have one on the right, one on the left. This is the brain structure that I've studied for the vast majority of my career. But there are other memories, motor memories. The memory that you have for how to get your keys into your lock in that special way to get it open. It took a little while to learn how to do that. Same form of memory that you use to learn how to hit a forehand and a backhand in tennis, for example. Very different brain structure. The striatum is involved in motor. Motor memories. So lots of different forms because we are remembering things in different ways in our lives.
Jonathan Wolf
I'd love to start to talk about what happens to our memories as we get older. It's had quite a big impact on me through my life. My grandmother got Alzheimer's and had a huge impact on my father, who basically has sort of. Ever since then, sort of lived his life feeling like that is the worst thing that might happen, but also, you know, very worried that that might happen to him.
Wendy
Yes.
Jonathan Wolf
And I think seeing someone go through this and sort of seeing these memories unravel is both awful, but also makes you realize how much it's the memories that sort of shape a person.
Wendy
Right, right.
Jonathan Wolf
It feels like, in general, memories weaken. I feel that already my memory is. It doesn't feel like it's quite as good as it was when I was 20. But I can see that obviously that can continue into old age. Why does that change as we age?
Wendy
Let me start with the good news. So often people, I'm just gonna say, at our age think, oh, my memory's getting worse. But actually, part of what you're experiencing is more interference. You're probably doing more and juggling more and, you know, more people, and you have more relationships to organize. Interference is very bad for your memory. When you're 12 years old, you don't have very many friends, and you don't have that much to remember. And so it's easier to keep things so that hopefully will be helpful to help interpret part of what you and I, you know, think. Oh, I can't remember that. Well, I certainly have a lot more things to juggle today than I did even 20 years ago.
Jonathan Wolf
May I just say, I love that.
Wendy
Okay.
Jonathan Wolf
Absolutely love the idea that my brain is still working and actually I'm just so busy.
Wendy
Yes.
Jonathan Wolf
It's not. My brain is already falling apart.
Wendy
No, not at all. And I think everyone listening to this podcast can appreciate that even more if you give yourself that moment of quiet meditation, self reflection to get rid of some of that interference of too many things going at the same time. Do not read your phone while you're walking down the street eating a good or bad breakfast. That is adding to your interference. That is why a regular kind of mindfulness practice is helpful. It is clearing the garbage away so you can focus on those things that you do need to remember. And in fact, I find that I'm better at remembering the things that are really important and kind of filtering out what is not good. But I do a regular daily meditative practice just for that purpose.
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Jonathan Wolf
Well, I'm going to come back to sort of your actionable advice a bit later, but I find it incredibly positive that you're saying your brain is working better now than it was before. I think that's very exciting. Clearly, late in life, memory loss is something that happens quite, absolutely, like a real risk. And I think a lot of people listening to this show.
Wendy
Yes.
Jonathan Wolf
When they talk to us, particularly those who've become Zoe members, talk about, like, what their health goals are. Interestingly, you know, brain health is often something they mention as much as physical health as a thing that they're worried about and they want to maintain.
Wendy
Yeah.
Jonathan Wolf
So if I'm fine now at 49, you know, what might happen as I get older? Why is it that memories don't continue to work, you know, perfectly, you know, right up to death for everybody?
Wendy
Well, again, let me start with the good news. Sometimes they do, and there's such a wide variety of aging, but when they don't. And my father also passed away with Alzheimer's disease. Yeah, thank you. And I saw that happening. I recognized it very early on. He couldn't remember how to get back from the coffee shop that he went to every afternoon. And that spatial memory is particularly dependent on the hippocampus. And when he came back complaining of that to my mother, I knew something was wrong with his hippocampus. He was eventually diagnosed with Alzheimer's dementia, which meant that the cells in his hippocampus were starting to die. The plaques and tangles started in the hippocampus and then spread out into his cortex. So what's happening there? That that is the cause of the most common form of dementia, Alzheimer's dementia. And that means that again, starting with the good news, long term memories from your childhood, when you grew up, your, you know, your high school years, are often something that you remember so well, those are no longer stored in the hippocampus. So those memories, in as much as you've kind of maintained them over your long life, are still there. But when you start to get damage to your hippocampus, you can no longer put new information into your long term memory. So your breakfast, your lunch from yesterday, not going in there. And so that starts to break down. I ask my students all the time, would you be the same person if you didn't have your four years of high school experience? And all of them say, no, I would absolutely not be the right person. So that damage to the hippocampus, that starts to happen slowly in dementia in older age, starts to wear away at your personal history and in your ability to do things and interact with the world.
Jonathan Wolf
So I'm looking for an analogy. Let me try this. Tell me if I'm completely wrong. So I'm listening to this, Vinny. It's a little bit like, you know, when you take a photo on your phone, it's just on your phone but then after a little while it like it backs it up into the cloud and then even if you lose your phone, you know it's still there in the cloud and you can access it.
Wendy
Right.
Jonathan Wolf
And is this a little bit of an analogy? You're saying you've got this hippocampus which a bit like my phone is dealing with this right now. But all going well. It's sort of pushing it into other parts of my brain whose name I've already forgotten.
Wendy
Yeah.
Jonathan Wolf
And sort of stores it. And that's what normally happens.
Wendy
Right.
Jonathan Wolf
And you're saying that in this example with Alzheimer's as we get like that process of like holding it in the first part just doesn't work. So I can't even make it through to this long term. Yeah, but you might still have the long term. Which is why I think one of the common things, you know, as a non doctor, not a scientist, you know, you meet people who are having some of these memory problems. Often they. They remember things a long time ago or like general parts of their life. But somehow the last few years can just be almost exactly. And they just skip over it as if it was happened.
Wendy
It's a strategy to kind of get through life. You use what comes up in your brain and because those new memories are not being laid down, you use what you have in there as habits and as reference. And you realize I saw this in my father. There was a long time where I think he was having memory problems. But he covered very, very well. Cause he knew the answer. He knew enough from the life that he was living about what to do when he needed to do it enough. But he was covering. And one day he couldn't remember how to get back. It was just eight blocks away, this coffee shop.
Jonathan Wolf
We had very similar experiences with my grandmother's. Interesting. I hadn't realized that the location thing was a particular thing. But getting lost on things that were. You know, I remember actually was with my. My cousin that she was very little at the time.
Wendy
Yeah.
Jonathan Wolf
And sort of got lost and it like didn't make sense. She was incredibly like on it woman. And so. But I hadn't. You're saying that this sort of loss of location related things is a sort of giveaway about this particular sort of damage?
Wendy
Yes.
Jonathan Wolf
Can I ask Wendy? Because, you know, we started talking about Alzheimer's in part because my own family experience. But I think that we think about forgetfulness and not being somehow quite as sharp as just a more common experience. And I would say most people feel that it's almost like inevitable experience. As you get older, is losing your memory just the same as getting Alzheimer's? And does everyone end up getting Alzheimer's if they live long enough?
Wendy
The longer you live, the higher probability you have of developing dementia and Alzheimer's disease. But there are lots of different reasons why memories might be harder to lay down. And one that is so relevant in this moment is stress and anxiety levels. Who does not have higher levels of stress and anxiety today than maybe 10 years ago before anybody had heard of COVID 19, for example? Stress is. Everybody has the example. You're in a stressful situation and you're asked a simple question. Oh, I can't remember. Does that mean you have dementia? No, it means that you are stressed. So that's one very common thing. I will say the stress and anxiety levels are double edged sword. I give the best podcasts that I ever give. When I'm just a little bit nervous, I'm not sure exactly what's gonna happen. I use that little bit of, you know, boost from stress and anxiety and if I go too far over, then I can't remember all the stories that I want to tell you. And if I'm too relaxed, then I also don't like my performance. We tend to catastrophize or clinicalize stress and anxiety. Like, oh, it's so terrible, I don't want any of it. No, every single one of us needs it in our lives. It is that motivational boost. You know, before we went through COVID 19, perhaps we had a better appreciation of it. I'll also say that particularly for our younger generation, social media is leading to higher levels of stress and anxiety. And that is not good. If you're in a constant state of, oh, I'm not good enough, I don't look this way or I don't have this. That is not good. But generally, little bit of stress can help your performance be at its peak.
Jonathan Wolf
And so is there like a slow drip by drip sort of decline in my brain as I get older? Because I think you were saying, like right now I'm fine. But if you put aside sort of before you get to something that you were calling sort of Alzheimer's or dementia, is there just a slow decline in my, in my brain? Which I think is what most people listening to this, that's sort of how they've been brought up in the same way that we're brought up, that when you're old, you can't climb stairs and you're sort of, you know, the same thing, is that your brain just steadily gets worse, like your muscles reduce. Is that accurate or.
Wendy
Yes, with aging, our muscle fibers degrade. And you're probably not gonna be as strong as you are at 75, as you were at 25. But there are lots of things that one can do to strengthen that brain muscle that you have. And that is where all the science comes in. The science of sleep you talk about so beautifully. The science of nutrition, not only for your muscles and your peripheral body, but for your brain. The science of exercise. I know we're gonna get to the science of social connection. We are social animals. And the longest running study of happiness in the world. It was started at Harvard in the 1920s. And what brings a happy life since the 1920s, from the 1920s till today is the number of social connections that you have in the world. So all of these things contribute to this beautiful organ that we all have in our heads and how it works and how you're working it every single day.
Jonathan Wolf
I would love to transition now to the thing that you're really studying and interested in, which is how exercise impacts the brain. And my producer has told me that you have brought something that you want to use as a sort of show and tell.
Wendy
Absolutely.
Jonathan Wolf
Would now be a good time for that?
Wendy
Absolutely.
Jonathan Wolf
We don't normally get show and tell on the podcast, so that's quite exciting.
Wendy
Okay, so I have a hat box here, and I'm putting on some rubber gloves and in this hat box.
Jonathan Wolf
Okay, it's definitely not a hat.
Wendy
Instead, what I've brought for you today is a real preserved human brain.
Jonathan Wolf
It's a real brain. Up until now, I thought it was just like a sort of clay model.
Wendy
No, no.
Jonathan Wolf
Now I'm completely freaked. Yes, it is a real brain.
Wendy
This is a real preserved human brain. Her name is Betty.
Jonathan Wolf
Betty.
Wendy
And she is the most photographed preserved human brain on the east coast of the United States. Cause I bring her. Well, I can't bring her out of state, but I bring her to all of my talks for thousands of students at nyu, where I teach. This is the front of the brain. This is the frontal lobe. This is right behind the forehead. Right here, the frontal lobe. Important for focus and attention, decision making. Back here. Here's the back of the brain. Right back here. This is the part of the brain that we see with so all of the nerves from your retina and your optic Nerve go from the front of your brain all the way back and they connect to this primary visual cortex right here.
Jonathan Wolf
So I'm actually seeing with the back of my head, even though I think I'm like at the front of my head. Actually it's all at the back.
Wendy
You're seeing with the back. And that is why that's crazy. If you've ever kind of bonked the back of your head, you see stars, right? Because you've poked the visual cortex. And so that evokes a perceptual sensation of visual stimulation because you poked the visual cortex. You don't get stars if you bonk the motor part of your brain, for example. So between the frontal lobe and the occipital lobe, the back of the brain is the parietal lobe, Important for processing relative spatial locations and decision making. My favorite lobe is the temporal lobe here. Right kind of below the temple. Why? Because that is where the hippocampus lives in a fact.
Jonathan Wolf
And that's what you were saying was where we store our memories as they're happening.
Wendy
We are processing those memories. It is encoding those memories into long term memory. And with repetition, those memories get stored out here in the outer covering the cortex. But down here, right below this part of the temporal lobe is where the hippocampus sits. And right here is called the cerebellum or small brain. This is really important for fine motor movements. If you play an instrument or anytime you walk down the street, it's actually a lot of coordination to walk without tripping. And that is because we have a cerebellum that's helping us with that. But this is somebody's whole life. Their personality, how they see, feel, think, smell, laugh about. The world is defined by the connections in this structure right here.
Jonathan Wolf
I mean, the first thing I'm struck by is how big it is. It's much bigger somehow than I really imagined it would be. I mean, it's like a good sized sort of melon size. It's a lot bigger than my heart, I think would be, isn't it? It's taken up most of what's inside my skull. I guess looking at it, it's like really big. It's not a very appealing color. It's a sort of brown. I at first thought it was clay. When you took it out, it's like, oh, you've got a model. Because it looks sort of soft and a bit squishy.
Wendy
So it's brown. It's this brown because it's been sitting in formaldehyde. For many, many years. It's much lighter in our actual heads. But you're right that it's large, it is dense. I mean, this. It's not just a fluffy structure. And if I'm pulling the two hemispheres from the right and left open, if you can see that, how deep it goes in, this is folded cortical mass. And the amount of folds basically correlate to our brain power as humans. This would be much larger. If I unfolded the cortical surface out on this table, it would drape over the edge of the table that you and I are sitting at right now. So, for example, a rat brain is much smaller. It's just an inch, and it is smooth. No folds. Sorry, rats. I mean, you navigate the subways in New York beautifully, but you don't have the computational power that humans have as we're seeing right here.
Jonathan Wolf
I mean, I just said it's large, but actually it's pretty small. Right, you're fitting it in just in.
Wendy
Yeah, in my palms.
Jonathan Wolf
You're actually able to hold it in your palms quite comfortably. Like, it weighs how much?
Wendy
About £3.
Jonathan Wolf
About £3. It's just over a kilogram. And I compare that with the enormous, enormous number of servers that are having to be done for things like ChatGPT that people listen to. This there's definitely not as clever as a human being yet. And you just see just how extraordinarily efficient that is as a. Like a thinking machine.
Wendy
Exactly.
Jonathan Wolf
And that it has, like, personality and sense of self and self awareness and consciousness, all these things. Rather. It's amazing.
Wendy
I'm thinking of a different answer to the question you asked at the top of the show, which is, do you realize that there's only two kinds of cells that make up the entire human brain?
Jonathan Wolf
No, I had no idea.
Wendy
Neurons, which are the workhorse cells and glia. They have been described as support cells, but we now know they're doing much more in terms of computation, even some cognitive functions, but only two basic types. And the connections between those two simple types of brain cells are what defines us as people and allows us to think and fall in love and remember the birth of our children and all the other things that the brain does.
Jonathan Wolf
And it's sort of soft. Right. There's nothing rigid holding this together.
Wendy
Well, it's like firm tofu, I would say, in the head, firm tofu is quite soft.
Jonathan Wolf
Like, if I. If I. That is remarkable.
Wendy
I mean, that is why helmets are so important.
Jonathan Wolf
So it's going exactly the same way. Like, when you look at that. It makes you think like how unprotected it is if you fall off your bicycle or somebody tackles you in a sporting game or something like that. It's really remarkable.
Wendy
It is. But I will say this is another thing that people don't realize. So surrounding this, of course, is our skull, which is hard. I don't want my precious brain banging up onto the skull. And it doesn't because between the skull and the brain. Think of it as a fabric sack that covers the entire brain. Between the sac and the brain is a water. It's cerebral spinal fluid. So it's like a little waterbed for your brain, but that is the protection between your precious neurons and glia in your brain and the hard skull or the football player or soccer player coming at you to tackle you. So. So I'm a big proponent of non trauma. No trauma for your brain.
Jonathan Wolf
Amazing.
Wendy
Would you like to hold Betty?
Jonathan Wolf
So I'm a little intimidated, but I also feel one's supposed to face up to one's fear. So yes, I think I would.
Wendy
Okay.
Jonathan Wolf
And I'm guessing I need a pair of gloves.
Wendy
Yes, you should put gloves on.
Jonathan Wolf
So how old is Betty?
Wendy
So Betty has been in the center for Neuroscience, my department at NYU, since I got there 26 years ago.
Jonathan Wolf
Wow. I am as intimidated as I am when like a friend passes over their three day old baby and you know, the one thing you mustn't do is drop the baby.
Wendy
Just don't drop Betty.
Jonathan Wolf
Just don't drop Betty.
Wendy
But okay, okay, there you go. Impressions.
Jonathan Wolf
Well, the first thing I say is Betty is heavy because on the outside looks sort of a little squishy. So you think it's going to be like a sponge, but Betty is heavy like a bag.
Wendy
Yes, Betty is dense, a couple of.
Jonathan Wolf
Pounds, a kilogram, something like that. It's very weird to imagine that you're holding the brain of a real human being and that all the emotions and fears and loves were happening in here.
Wendy
Yes.
Jonathan Wolf
I think the other thing that I'm struck by completely differently from that is we do a lot of AI at Zoe. There's lots of data scientists and computer scientists and you know, everybody listening will be familiar with things like ChatGPT recently that are sort of remarkably human. Like in some ways they use huge numbers of computers taking up vast amounts of power and huge amounts of space. And they're not as smart as Betty would have been or able to do many things or be self aware. And yet Betty's in fact really small and squishy. And it's remarkable, right, the capacity within our brains. When you look at it like that, it seems crazy to think that you can think and feel with this. It's amazing.
Wendy
Absolutely, yes. Small and squishy, yet the most complex structure known to humankind. You are holding in your hands right now, Jonathan. And that's what I think about every time I pull Betty out of this hatbox. This was somebody's whole life. I mean, I've spent my whole career trying to understand how that works. We know an enormous amount about neuroscience, but we don't know what happens in the brain when we fall in love. Exactly. What are those synapses that go off?
Jonathan Wolf
There is no, like, love cortex in here.
Wendy
There's not a love cortex. We know that our fear areas of the brain don't work as well, so we tend to become more fearless when we are in the throes of deep romantic love.
Jonathan Wolf
I love that it is extraordinary. And I know that, you know, everybody working on AI Actually is basically wanting to learn more from the brain because it is so much more complicated and we understand so little. It's amazing. Thank you very much. I'm gonna pass her back. I'm gonna feel immediately, massively more relaxed to the point I passed her back and haven't dropped her. Thank you very, very much for bringing her in. I think it is really an amazing way for all of this to go from being very abstract because it's in the brain and hidden, to sort of seeing it for real. And this thought that there's things that I could do to actually make it work better for longer, it's. It's amazing. Okay, thank you.
Wendy
I'm going to put Betty down now so we can continue our. Our conversation.
Jonathan Wolf
Well, that's quite intense. Really. Remarkable. I have never seen someone's brain outside side of their skull before, and I'm okay with keeping it that way. I think seeing it in real life does make you, like, even more. See that this is this real organ. You know, it's not just this abstract personality, which is, I think, how I tend to think about it. And you were talking earlier about, you know, how as we get older, basically, this organ can get less efficient. Do any parts of it shrink, or is it just that it stops working as well?
Wendy
So lots of different things happen. There are loss of synaptic connections. Synapses are the connections between individual brain cells. And it's not so much. People think, oh, there's widespread cell death. Cells aren't dying. In normal aging, it's usually the synapses that leave and that are damaged. And that's the most common thing that's happening with aging.
Jonathan Wolf
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. So right now, if you could share a link to the show with one friend who would benefit from today's information, it would mean a great deal to me.
Dr. Wendy Suzuki
Thank you.
Jonathan Wolf
So basically, the connections between the different cells in my brain, there were lots of them, and there's less. And losing those somehow reduces how well it works and processes every part.
Wendy
But actually going back to something that we talked about before in terms of stress, not all of us have the level of stress that comes with ptsd. But we also know that ptsd, long term stress in situations of war, does lead to an overall shrinkage of the brain, particularly in the temporal lobe. And that is because we know that high levels of cortisol can first start to damage those synapses, the connections, but then high levels of constant cortisol will start to damage your brain cells. That's not the most common thing that happens with aging, but that is something that we know is leading to the shrinkage that people are scared that it's happening to your brain. It does happen. It's not the most common thing happening with the vast majority of the population.
Jonathan Wolf
So most people are not gonna see this. But if you're under very intense stress and you talked about combat or something like literally the brain itself, parts of the brain will get smaller.
Wendy
Yes.
Jonathan Wolf
So is it possible to do anything to prevent the loss of these connections between these cells, prevent this damage to your brain as you get older?
Wendy
Yeah. So this is kind of the topic that I've studied for the vast majority of my career, which is the area of brain plasticity. How things in the environment, things that you do, how you live your life, how it affects literally the anatomy, physiology, and function of your brain. And there's two flavors of brain plasticity. Positive brain plasticity, where the experiences that you give yourself can increase size, increase function. And negative brain plasticity, which we just talked about, ptsd, long term stress can take those connections away, can make sizes smaller in particular brain areas.
Jonathan Wolf
And are there real scientific studies that have demonstrated this?
Wendy
Absolutely. For all the musicians out there, it's clearly shown that long term practice at a level of a professional musician will increase the size of your motor cortex specific for that. If you're a violinist, it's the left hand that gets so much work. If you're a pianist, it's both hands that will change the size and representation of those motor areas that you are working.
Jonathan Wolf
So my mother made me practice an instrument every morning from when I was 4. And I kept doing this until I was grown up. And then I dropped it quite fast after I left home. I'm sorry, mum. Have I got any long term benefit from that or is the fact that I've dropped it now means that I like lost out on any of the.
Wendy
Plus, you probably have a little, little bit of it left. You could probably relearn pieces faster than somebody that never practiced for those years. But no, it doesn't last for a lifetime. You can't kind of take one summer and say, okay, here's the exercise I'm gonna do for the rest of my life and it's gonna last. It really does have to be a regular habit that you form.
Jonathan Wolf
I had a terrible feeling you were gonna say it's a bit like exercise and good food, right? I can't just eat really well last decade and then like now just have ice cream and burgers.
Wendy
Sadly, sadly, no.
Jonathan Wolf
So other than playing music really well every day for the rest of my life, is there anything else that can help to improve this brain health?
Wendy
Absolutely. So many different things. I'm gonna start with my favorite, which is moving your body. Physical activity is so powerful. As I said, my most amazing thing is moving your body is the most transformative thing that you can do for your brain. And I think people realize that moving your body is great for your heart and cardiovascular and your muscles, but they don't realize that in this sense your brain kind of like, it acts kind of like a muscle. And what is happening is different from when you're using weights or running for your muscles. What happens is every single time you move your body, there is a rush of neurochemicals that gets released in your brain. And those neurochemicals is the secret for why exercise is so transformative. Let's go for the immediate benefits that happen with this rush of neurochemicals. You get dopamine, serotonin, noradrenaline, endorphins released with exercise. And I'm not talking about marathon running. I'm talking about a power walk, a 10 minute walk that you can take at lunch. Walk up and down the stairs during your day that can lead to this rush of neurochemicals that I like to call a bubble bath of neurochemicals. That happens every time you move your body. And that's gonna lead to an immediate mood boost. Now, is that gonna change your mood for the rest of your life? No. The duration of that mood boost is going to depend on how long, how hard you worked out. And there's a bell shaped curve there, but that's not all you get. Moving your body also improves the function of your prefrontal cortex, the one right behind your forehead, really critical for your ability to shift and focus attention. You and I, as a podcaster and as a teacher, need our prefrontal cortex to remember questions that were asked and the questions we wanna bring up, critical. And that single bout of exercise can help with the functioning of that prefrontal cortex. And the third thing you get is reaction time. So your ability to respond to a question is faster after a single workout than if you didn't work out at all. And this is all having to do with that bubble bath that you're giving your brain. But the most transformative thing happens when you don't just do a one off of exercise. I was just gonna try it once. Okay, I did it. I got the bubble bath. You know, give me all the benefits. You get a short term benefit with a single exercise bout. Let's say you include more exercise in your life, which I call long term exercise, and you do that on a regular basis. That means your brain is getting more of a bubble bath. And here I'm gonna add one other element to that bubble bath that gets released every time, which is a growth factor called bdnf, or brain derived neurotrophic factor. This goes to my favorite structure in the brain, the hippocampus. And it actually helps the hippocampus grow brand new brain cells. So I like to say regular exercise is going to make your hippocampus big and fat and fluffy. And that is what you want. You want the biggest, fattest, fluffiest hippocampus that, that you can have. It's also actually changing the size of the prefrontal cortex, not because of new cells, but because of new synapses. And so that is the transformation.
Jonathan Wolf
That all sounds pretty amazing. And if I just caught that bit at the end, what you're saying is that although you said at the beginning that maybe our brain overall doesn't grow, you're saying that this particular part, which is your favorite part of the brain. I never had a favorite part of the brain before, but I like that you have a favorite part of the Brain actually grows as you are doing this exercise on a regular basis?
Wendy
Yes, it does. And also, even if you don't do any exercise, every one of us has a little bit of. It's called neurogenesis, the birth of brand new brain cells in our hippocampus. But with exercise, I like to think of the image of a watering can of growth factor that goes up and down the hippocampus every time I'm working out. This is my nerdy motivation to work out in the morning is I want that watering can of growth factor going into my hippocampus and growing as many brand new brain cells, because those brain cells means my memory is going to be better and my hippocampus is going to be bigger and fatter and fluffier. I have Alzheimer's in my DNA. My father passed away with Alzheimer's, and I am not curing Alzheimer's with my exercise and the increase in BDNF in my hippocampus. But I'm making the hippocampus as big and fluffy as it can be, so that it's gonna take longer for that disease to start to affect my memory than if I didn't work out and my hippocampus was skinny and small and unfluffy. I don't know what the opposite of fluffy is, but that is the goal of, and that is the power of what exercise is doing for every single one of us.
Jonathan Wolf
And Wendy, I just want to be really clear about this. If you are doing this exercise regularly, it actually does reduce your risk of getting dementia.
Wendy
As a result, there are many correlational studies showing that the more you work out either in mid age or in older age, the lower the probability you have of developing dementia. But overall, you know, as we get older and older and older, still overall increasing your probability of getting that dementia. But it makes sense with the anatomy and what we know about the positive brain plasticity that physical activity gives to your brain. That staving off of the onset of dementia with regular exercise makes perfect sense.
Jonathan Wolf
With the neuroscience that we know, that's amazing. And when you say brain plasticity, that's the same thing about it being flexible and able to make these connections.
Wendy
Yes, brain plasticity refers to the change in anatomy, physiology and or function. It's a broad term. So what I'm telling you about with exercise is a literal change in anatomy. And I should point out that not all brain areas in the adult human brain can grow new brain cells. In fact, only two can. One is the olfactory bulb that isn't affected by exercise, but is affected by lots of different smells. So you'd expect a sommelier or a chef to have a big fat, fluffy olfactory bulb.
Jonathan Wolf
I've never heard of that before.
Wendy
And the brain area that all of us have the potential to grow new brain cells is the hippocampus. And the best way to do that is to move your body more.
Jonathan Wolf
Is there a point at which it's too late for exercise to help with your brain health? Like, you know, if I'm listening to this and I'm 80, is it like there's nothing more to be done or does this affect relevant for anybody?
Wendy
It is never too late to start to move your body. And there are studies showing that even people in the early stages of dementia with mild cognitive impairment improved their dementia score with regular physical activity and appropriate for that age group. They're not running marathons, they are walking, supervised, either on a track or on a treadmill. But that absolutely shows that. In fact, the other amazing finding is, is that they have shown that people, even in their 90s, are growing new hippocampal brain cells. So even that ability to grow new hippocampal cells is there in your 90s. That doesn't prove that with exercise you can grow more, but you are still getting new cells. There's the signature of those brand new cells even in a 90 year old.
Jonathan Wolf
That's amazing. And I love the idea that it's never too late to do something, which I always find incredibly empowering. I think one of the things that all the different conversations that we've had on the podcast over the last couple of years is I was sort of brought up with this idea that your genes are your destiny and there's basically nothing you can do. You're just like fixed on this path. And what I love listening to you is you're saying, like, Even in your 90s, there are things that you could do that can really affect your outcome and it doesn't guarantee anything. But the point is you're not just sort of stuck on the path. And I always find that, at least for me, it feels incredibly empowering. Like there's something that I can do before we move to like, really actionable advice about practically what we might do. I just wanted to pick up on one other thing because you talked about the sort of amazing short term impact of doing this exercise with this bubble bath of like happy chemicals whose names I've already forgotten. Is there any long term impact on sort of psychological, like how you feel and Your sort of regular cognition. Not anymore. Talking about, like, am I gonna be protected, you know, when I'm much, much older, but like, if I'm doing this regularly, is this gonna have effect on me after a week or a month or a few months?
Wendy
Yes, yes, absolutely. So let me tell you the two most common findings in the whole wide literature. The effects of exercise on the brain. Number one is long term exercise changes your baseline mood state. You have higher levels of good emotions and lower levels of more difficult emotions. You know, stress, anxiety. Absolutely. Goes down. That is very, very common in the literature. And the second kind of equally common finding with exercise is that you get better, you improve your ability to shift and focus. Your attention. Predominantly dependent on the prefrontal cortex. I can't emphasize how important that is in our world when our attention is being, you know, torn from your phone to your laptop, to the people in front of you, to the bike that's about to, you know, run you over on the street. So many things that we have to pay attention to. And that improvement of prefrontal function is. You asked me, that's why I hesitated. You asked me, can exercise make you smarter? Improved attention is the, the actual finding that I point to, am I smarter with a better prefrontal function? That's why I hesitated. And my answer was, yes, I feel better. I'm able to perform better with a highly functioning prefrontal cortex. And there's also studies showing that hippocampal function changes, but it seems like you need longer, longer exercise regimens to really see the benefits of that. There was one really great study where six months of increased exercise. You can see the graph line going up. And it was only after a year where everybody started to merge on this. So this is not an immediate, you know, I'm gonna get a big, fat, fluffy hippocampus in two days. In the next two days. No, it takes a little time. This is cell growth and it makes sense. But there's also great evidence, particularly in animal studies, in showing how powerful exercise is to grow your hippocampus. It reminds me of all the amazing data from the blue zone areas. These are not people that go on a fad diet or a fad exercise regimen. These are people that live in the mountains all their life. They walk up and down and up and down the mountain, and they eat very little red meat and they eat a lot of pickles or all these things that are great for your gut microbiome, not for a fad their whole life. And what happens, they live to over 100 with good cognition, not, you know, degrading and that, that's it. How can you make not a fad diet, but how can you make this part of your everyday living?
Dr. Wendy Suzuki
I love that.
Jonathan Wolf
And we actually did a podcast with Dan around blue zones. So if anyone listening to this is, is interested, they can if they search for blue zones that they will find it. So somebody's listening. They're completely sold on exercise. What can they do? And do they have to become a marathon runner?
Wendy
Yeah, yeah. So first you don't have to become a marathon runner. Walking. Power walking works just fine for mood. That immediate mood benefit that we talked about after a single workout, just walking for 10 minutes, getting outside, walking for 10 minutes. I think so many of your listeners will have experienced that already. But the key for getting those long term changes, especially the big fat, fluffy hippocampus and prefrontal cortex, is doing anything with your body that increases your heart rate. That's called aerobic activity. Let me emphasize again, power walking will get your heart rate up. And I like to say that even if you haven't started, it's not part of your regimen. It actually is faster to get your heart rate up when you're just starting out than if you have a regular exercise regimen. It's like, oh, I have to get into there for at least 30 minutes before my heart rate gets up. So all the beginners have a little advantage there. But every moment that you get that heart rate up for whatever you do, including fun things like dancing, gardening, walking around a museum, there's so many creative ways that you can do this. That is what's going to give you that big, fat, fluffy hippocampus, prefrontal cortex and beautiful brain.
Jonathan Wolf
And is it more important therefore to be doing faster steps than to be doing more steps?
Wendy
As I listen to that, that's a great question. I would say that those that are doing lots of steps, maybe at a lower aerobic activity, can put on their to do list, add more fast steps into that. And those that are doing small numbers of steps, that maybe have higher aerobic activity. You know, I like to say every step counts, every step counts. So don't People come up to me all the time. I go, all I do is walk. I'm like, that is great. You know, celebrate that people don't realize that walking to the store, walking from your car to the store and walking around a shopping mall, all of that counts too. So just to try and get more. And I think the secret is not just More make it fun. Because if it's not fun and enjoyable, you're not gonna do it.
Jonathan Wolf
That's fascinating. What sort of exercise target should someone be thinking about? And I'm sure you're saying it's different based upon their starting point, but like, how often a week, like how much time do people need to devote? Cause I think sometimes you listen to things on the Internet. It's like, well, if you're not doing three hours of crazy exercise, none of this matters. Is that the reality for your brain?
Wendy
No, it's not. And I can be very specific because one of my goals over the last 10 years has been to try and head towards a prescription and of exercise, like, people wanna know exactly how much. So I'm gonna start with a study we did in people that were not exercising so much less than 20 minutes a week for the last three months, 20 minutes of exercise per week. And what we showed is in those people that three times a week, aerobic exercise, 45 minutes each. There's the specificity. Got them. Baseline mood changes, improved prefrontal function and improved hippocampal function. Three months of that.
Jonathan Wolf
And say again, how much was the exercise they were having to do?
Wendy
Three times. Actually, what they ended up doing was between two and three times a week. I think it was 2.6 times a week on average. This group did 45 minutes. Each of it happened to be a spin class. So we chose a class where clearly the goal was aerobic activity. So that got these brain plasticity changes. That was. We were thrilled with that. And then I have one more piece of data to give you, which is what about mid fit people that are exercising maybe two on average, two times a week, But a good spin class or run or something like that. What about them? Well, we did a study in that population and we said, okay, exercise as much as you want. For the next three months, we're gonna give you free workouts again at a spin studio. And we had people that went seven days a week for a 45 minute class. And those that stayed at two to three times. Yeah, two times a week. What we found is every rotation of the wheel helped. The more you worked out at this mid fit level, the more benefit you got in all of these things in mood, in focus, and in memory. I like to say every step, every drop of sweat counts. Whether you're just starting out, you're in the middle, and you know, Olympic athletes. I would love to do a study on you because I know what the outcome is and I would love to show that. But most of us are not Olympic athletes, which is why I started with the lower fit people and the people exercising twice a week.
Dr. Wendy Suzuki
Know someone who complains that they struggle to focus?
Jonathan Wolf
Perhaps they complain about brain fog.
Dr. Wendy Suzuki
Share this episode with them today. Give them the tools to enhance their mental sharpness with the latest scientific knowledge.
Jonathan Wolf
I'm sure they'll thank you. I know you said that there's a way to each your way to a sharper mind. Could you tell us more?
Wendy
Yeah. So the amazing data on nutrition and the brain focuses mostly on the Mediterranean diet and or the mind diet that focuses on decreasing inflammation, which we know is very bad for the progression of dementia and Alzheimer's disease. Alzheimer's is the most common form of dementia. I didn't mean to refer to those two things as separate. They are one in the same. Also, it comes up back in the blue zones. A lot of these blue zone areas follow that general pattern of less red meat, more colorful, lots of fruits and fresh vegetables. Not exactly vegetarianism, but lots of fruits and vegetables. And so those are the things that have been associated with the longest longevity and the strongest kind of cognitive function over aging. So, I mean, personally, that is what I try and follow.
Jonathan Wolf
Amazing. We're very interested in the Mediterranean diet and sort of food more, more generally. And then we're really interested in this question about personalization on top. And one of the things that our research and other research has shown is that the way that people respond to the Mediterranean diet varies from person to person. So it's not all exactly the same. And, you know, our hypothesis has been that partly that's because of the different gut microbiomes that people have. And so over the last year or so, we made a big breakthrough where we identified 50 gut bacteria which cause sort of good gut bacteria, 50 bacteria that cause bad gut bacteria that are linked to positive health markers and negative health markers. And when you become a Zoe member, you get this personalized nutrition program which tells people how can you add in particular foods? It's actually targeting getting more of these good bacteria. And we found with this randomized control trial that we published in Nature Medicine a few months ago that after about sort of four to five months of following this personalized nutrition program, the vast majority of these Zoe members actually had a better gut microbiome. And, Wendy, are you surprised by that, or does it sort of fit in with, I guess, what you've seen in this thinking about the way in which the diet is linking to your health and your brain?
Wendy
It doesn't Shock me. And I should say that I have not touched the nutritional aspect. I did not control nutrition in these studies. And I think that that's why the studies that you and your colleagues are doing are so important. Yes. I think that's such an exciting area of research, the link between the gut and the brain, which is a new and emerging and really, really exciting research area. And just like so much in our health, it's never gonna be one size fits all, and it's easier to speak to the generality. And that's where the general Mediterranean diet. Great, Right. But it's so, so powerful to know that there is not just the idea of personalization, but there is kind of actionable items that you can add to that. So it doesn't surprise me. As you know, it's hard to control what people eat. It's hard enough to control how they move their body. To take on both at the same time. I need 10 times the number of team members as I think you can appreciate.
Jonathan Wolf
So I can totally appreciate. And I think this is an area that we're increasingly interest. Think that it's interesting that you mentioned sort of inflammation has been an important part of what you think is going on in the brain, because that seems to be what a lot of the scientists who've been coming on this podcast are talking about, this role between food and the microbiome. Meaning that. A simple picture that I understand is that most people walking around in the Western world now are just like, living with a lot more inflammation than we did in the past. And it's interesting we that you're talking about this affecting the brain, and they're often talking about it affecting other parts of our health.
Wendy
Yes. Yeah. There's more and more research on how bad inflammation is for the brain. I mean, that's one of the things that exercise can help with. That's why we need all of us working. We all can't be the experts in all of these different things, but they all work together in this amazing kind of physiology that we have.
Jonathan Wolf
Can I finish with one final question?
Wendy
Sure.
Jonathan Wolf
So I think a lot of listeners here are going to be going away feeling very motivated, but also I think often there's like a big gap from motivation to doing something. How could someone who's listening to and saying, I want to develop my own brain health routine.
Wendy
Yeah.
Jonathan Wolf
How can they do that and not sort of just feel stuck? What would be the, like, the key components you would be suggesting to somebody so they could go and keep going?
Wendy
Yeah. So this is what I suggest to my students, and it is the idea of a personal experiment, a personal exercise experiment. And the idea is to choose a doable increase in physical activity that you can fit into your very busy schedule on a regular basis and note what that does to these things we've been talking about to your mood is probably the easiest to modify. In fact, you are the best arbiter of what your mood is. There's not a good external measurement of your mood, but also focus and energy levels are also great to use. And so the idea is kind of monitor how you're feeling on a regular week, change this for a week, once a day, make it doable, make it something that can fit into your schedule. And note that and everybody can getting more sensitive to how exercise is affecting you. I mean, I'm sure this may be part of what you challenge your Zoe members to do. What does a sugar filled diet make you feel? I know that it makes me feel awful, but in fact, by contrast, a fruit filled summer diet, Mediterranean, pretending like I'm in Italy makes me feel wonderful. So same thing with exercise. And that is so powerful because you can start to use that personal sensitivity to create your own workout and to add in. You don't want to add too much either because too much is going to make your muscles hurt and make you too tired. You can't live in your day. What is that perfect amount of movement that makes your brain work better, makes you feel better?
Jonathan Wolf
And Wendy, you are basically one of the world's experts on exercise and the brain, maybe the world's expert on this. You're also obviously very busy. So I think everyone's gonna want to know. What's your personal exercise routine?
Wendy
Yes. So my personal exercise routine kind of developed during the pandemic. I used to be a regular gym goer and then couldn't go to the gym during the pandemic. So I started doing online workouts and I loved the convenience of being able to do that. So even today I do 30 minute cardio strength kind of workout. And when I need a rest and a stretch, I'll add a yoga, a 30 minute yoga. For me, 30 minutes was perfect because it fits into my schedule. I could push hard and I'm not so sore the next day. Even though if I try and really push really hard and I feel the difference during my day when I do that, I did it this morning and I could tell that I did it. Of course, if I have a 4am flight, I don't do it. But building that muscle of consistency and finding that duration that is right for you at your age. And your fitness level was key for me. But that's what I do in my life.
Jonathan Wolf
So 30 minutes a day. Do you have a lot of equipment that you need at home in order to do what you're doing?
Wendy
I do. I have a yoga mat and I have a set of weights. And every time I use the weights, I want like two more, maybe a five and a eight. But I just use what I have, and it's great. I know what pushes me, which is really higher. Cardio with weights is a great way to get your heart rate up. And I love kickboxing. I also know what I love. I love doing kickboxing workouts, which is really, really fun. And then I always say yes to an invitation, a class with other people, not in my living room. So that's how I do it.
Jonathan Wolf
Amazing. So that sounds. Kickboxing sounded a bit intimidating, but until you said that, that all sounds quite accessible. You're saying like a yoga mat, a couple of weights, and like something like an online class that you can just dial into and that can achieve all these amazing benefits you're describing.
Wendy
Absolutely. And, you know, I needed to go with other people, with a really motivating instructor that had really great music, and I did that for many years. But I built my regular exercise muscle there, so that's why I can do it. Maybe you need to go with a friend. Maybe you need to recruit a friend. Because a friend. And like, being there in a class where everybody can watch you was very motivating for me earlier in my exercise journey.
Jonathan Wolf
I think that's fascinating. I mean, my own personal experience is what I really need is a trainer, which is a bit like having a class and a friend.
Wendy
Yes, absolutely.
Jonathan Wolf
Because it's the commitment. Because basically, if I don't have that, I'll skip it and I'll do some more work. But if I have somebody who's waiting for me, I absolutely turn up because it would be, you know, be rude not to. And that is an enormous part of the thing that makes me do the exercise. Because the truth is, I've done it for quite a long time now, since I've started to realize it's really important for my health.
Wendy
Yeah.
Jonathan Wolf
But I've never quite hit the point where I really feel good about it in advance. I'm always reluctant before I start, and then afterwards I feel really good. So I need that sort of reason to be pulled. Wendy, I thought that was brilliant. I would like to try and do A quick summary, if that's all right. Sure, you just let me know if I get anything wrong and correct it. So then we started by saying that the longer that we live, the higher the risks we have of dementia or some other sort of issue with our brain. But the good news is there are things that you can do about it. And we mainly talked about exercise. And you gave this brilliant vision that, like, just moving my body in a power walk creates this, like, I think you said, bubble bath of neurochemicals and they have an immediate impact. So actually I can, like, remember things better, I can have a better reaction time, I can feel better just almost immediately after that because of all these chemicals. And if I do that regularly, I start to get all of these other benefits. And you said, actually, in that case, I can grow new brain cells. And in part of my brain that was the hippocampus, is that right? Which you pointed out on the brain. But I can't remember what it is. It gets bigger, fatter and fluffier. And these are all good things. And even if you're listening in your 90s, you could be doing something and you could actually be improving it. So it's amazing. It's not just something that you have to do when you're twenties and the more that you work out, the lower the probability that you will develop dementia. But it's not just about avoiding Alzheimer's and things like that. Actually, long term exercise has lots of other benefits and you said it can improve your mood in the long term, like really reduce anxiety and stress, make you feel happier and that therefore it's like just all round great for you. And then we got on to say, what could you actually do? And I think the thing there again was it's amazingly accessible. What you said was that even if you are just walking for 10 minutes, you can have an immediate impact on your mood. That the key thing, I think you said is you need to raise your heart rate. So aerobic, meaning raising your heart rate, you said. So actually, just power walking can do that. Dancing or gardening. And actually, if you aren't doing a lot of this, I love this, you're actually an advantage. If you're like Peter Attia, you've got to work for three hours before you get any benefit. But if you're a normal person, I can raise my heart rate really fast because I'm not that fit. So you can get a benefit really fast. And you said, the science says that even two to three times a week of 45 minute exercise had a real impact on the brain. But wherever you are, if you lift your exercise, it gets better and that will improve your mood, your focus, your memory. And you talked about your own experience where you know you're doing this every day because you're clearly maximizing your brain health, given what you described about your own personal experience. And even then, 30 minutes a day you're managing, patching you do from home and you believe you're really making a difference to your brain.
Wendy
Yeah.
Jonathan Wolf
Yes. It's amazing. Thank you for sharing all of that.
Wendy
Thank you for having me.
Dr. Wendy Suzuki
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.
Jonathan Wolf
Companion to better health for life.
Dr. Wendy Suzuki
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.
Jonathan Wolf
To help you shift your food choices.
Dr. Wendy Suzuki
To steadily improve your health. I rely on Zoe's advice every day and truly it has transformed how I feel. Will you 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 Willem. The Zoe Science and Nutrition podcast is not medical advice and if you have any medical concerns, please consult your doctor.
Jonathan Wolf
See you next time.
Podcast Summary: "ZOE Science & Nutrition" Featuring Dr. Wendy Suzuki
Episode Title: You Might Also Like: ZOE Science & Nutrition
Release Date: February 21, 2025
Host: Jonathan Wolf
Guest: Dr. Wendy Suzuki, Professor of Neuroscience at New York University and Author of Healthy Brain, Happy Life
In this episode of ZOE Science & Nutrition, host Jonathan Wolf welcomes Dr. Wendy Suzuki, a renowned neuroscientist, to discuss groundbreaking research on brain health. Dr. Suzuki delves into how lifestyle choices, particularly exercise and nutrition, can significantly impact cognitive functions, memory retention, and the prevention of dementia.
(00:00 - 02:28)
Jonathan initiates the conversation with a rapid round of questions, challenging Dr. Suzuki to respond succinctly:
Do our brains shrink as we age?
Dr. Suzuki: "No." (02:02)
Can adults grow their brains?
Dr. Suzuki: "Yes." (02:06)
Do certain exercises make you smarter?
Dr. Suzuki: "Yes." (02:11)
Is the risk of dementia fixed in adulthood?
Dr. Suzuki: "No." (02:15)
Can walking reduce dementia risk?
Dr. Suzuki: "Yes." (02:20)
Most surprising brain discovery?
Dr. Suzuki: "Moving your body is the most transformative thing for brain health." (02:28)
(02:37 - 05:44)
Dr. Suzuki explains the mechanisms behind why certain memories are vivid while others fade:
Emotional Resonance:
Memories tied to strong emotions, facilitated by the amygdala, are more likely to stick.
Dr. Suzuki: "Emotional resonance is so powerful in allowing things... to stick in your memories." (03:22)
Repetition and Association:
Repeating actions or associating new information with existing memories strengthens retention.
Novelty:
New and unique experiences are more memorable due to their distinctive nature.
(05:44 - 07:32)
Dr. Suzuki outlines various memory types and their corresponding brain structures:
Episodic Memory:
Linked to the hippocampus, responsible for personal events and facts.
Motor Memory:
Governed by the striatum, essential for physical tasks like playing an instrument or sports.
(07:32 - 13:32)
Discussing the impact of aging, Dr. Suzuki highlights:
Interference Over Time:
Increased responsibilities and information can lead to memory interference, making recall more challenging.
Alzheimer's and Dementia:
Progressive loss of hippocampal cells leads to difficulty forming new memories. Existing long-term memories remain until disease progression affects them.
Protective Factors:
Regular exercise and stress management can mitigate the risk and progression of memory-related disorders.
(13:32 - 30:29)
Dr. Suzuki offers a detailed tour of the human brain using a preserved specimen named Betty:
Frontal Lobe:
Dr. Suzuki: "Important for focus and attention, decision making." (20:08)
Occipital Lobe:
Processes visual information received from the retina.
Dr. Suzuki: "You see with the back of your head." (21:16)
Parietal Lobe:
Handles spatial orientation and processing.
Temporal Lobe and Hippocampus:
Central to memory encoding and retrieval.
Cerebellum:
Coordinates fine motor movements.
Dr. Suzuki emphasizes the brain's complexity and vulnerability, underscoring the importance of protecting it from trauma.
(31:06 - 34:07)
Positive Brain Plasticity:
Enhancements through activities like playing an instrument can increase the size and function of specific brain areas.
Dr. Suzuki: "Long term exercise is going to make your hippocampus big and fat and fluffy." (34:07)
Negative Brain Plasticity:
Chronic stress and trauma can degrade brain structures, particularly in the hippocampus, leading to cognitive decline.
(34:07 - 60:07)
Dr. Suzuki passionately discusses how physical activity transforms brain health:
Neurochemical Release:
Exercise triggers the release of dopamine, serotonin, noradrenaline, and endorphins, providing immediate mood boosts.
Dr. Suzuki: "It's a bubble bath of neurochemicals." (35:19)
Brain-Derived Neurotrophic Factor (BDNF):
Regular exercise increases BDNF levels, promoting the growth of new neurons in the hippocampus.
Dr. Suzuki: "Regular exercise is going to make your hippocampus big and fat and fluffy." (37:59)
Cognitive Benefits:
Enhanced mood, improved focus, faster reaction times, and increased resilience against dementia.
Exercise Recommendations:
Never Too Late to Start:
Even individuals in their 90s can experience cognitive benefits from beginning an exercise regimen.
Personal Routine:
Dr. Suzuki shares her 30-minute daily workouts, combining cardio, strength training, and yoga, emphasizing consistency and enjoyment.
(53:11 - 57:35)
Mediterranean and Mind Diets:
Emphasize fruits, vegetables, and reduced red meat to decrease inflammation, a key factor in dementia progression.
Gut-Brain Axis:
Personalized nutrition, influenced by individual microbiomes, can further enhance brain health.
Dr. Suzuki: "The link between the gut and the brain is a new and emerging... exciting research area." (55:32)
ZOE's Research:
Jonathan Wolf discusses how personalized nutrition programs based on gut microbiome analysis can optimize individual health outcomes.
(57:35 - 65:48)
Dr. Suzuki offers actionable steps to enhance brain health:
Incorporate Regular Exercise:
Adopt a Healthy Diet:
Manage Stress and Anxiety:
Personal Experimentation:
Stay Socially Connected:
Leverage Personalized Programs:
Dr. Suzuki: "Find that perfect amount of movement that makes your brain work better, makes you feel better." (58:01)
On Memory Formation:
"Emotional resonance is so powerful in allowing things... to stick in your memories." — Dr. Suzuki (03:22)
On Exercise's Immediate Impact:
"It's a bubble bath of neurochemicals." — Dr. Suzuki (35:19)
On Brain Plasticity:
"Regular exercise is going to make your hippocampus big and fat and fluffy." — Dr. Suzuki (34:07)
On Personalized Nutrition:
"The link between the gut and the brain is a new and emerging... exciting research area." — Dr. Suzuki (55:32)
On Consistency in Exercise:
"Find that perfect amount of movement that makes your brain work better, makes you feel better." — Dr. Suzuki (58:01)
Dr. Wendy Suzuki provides compelling insights into how deliberate lifestyle choices—particularly regular aerobic exercise and a Mediterranean-style diet—can profoundly influence brain health. Her research underscores the brain's remarkable plasticity, showcasing that it's never too late to adopt habits that enhance cognitive function and reduce the risk of neurodegenerative diseases. Listeners are encouraged to implement manageable changes, monitor their effects, and embrace personalized approaches to optimize their mental and physical well-being.
Additional Notes:
The episode includes advertisements for ZOE's personalized nutrition programs, which integrate gut microbiome analysis to tailor dietary recommendations.
For more information on the discussed topics, listeners are encouraged to consult Dr. Suzuki's book, Healthy Brain, Happy Life, and explore ZOE's membership programs.