Understanding Dementia: Causes, Risks, and Prevention Strategies

In this video, the speaker discusses the causes and mechanisms behind dementia, as well as ways to prevent or slow its progression. They emphasize understanding the brain basics and addressing risk factors such as neuroinflammation, less education, hearing loss, hypertension, sedentary lifestyle, insulin resistance, and nutrient deficiencies. The speaker suggests adopting a mentally and physically active lifestyle, engaging in regular exercise, following a low-carb and high-fat diet, and getting adequate nutrition. They also emphasize the importance of early intervention and motivation in addressing dementia.

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Key Insights

  • Dementia is a feared condition, but understanding its mechanisms and risk factors can help prevent, slow down, or even reverse it.
  • Genetics is not the dominant factor in most cases of dementia; multifactorial risk factors play a significant role.
  • Neuroinflammation is a common mechanism behind several risk factors, including traumatic brain injury, excessive alcohol consumption, stress, and air pollution.
  • Microglia, the immune cells in the brain, can become persistently activated, leading to increased inflammation in neurodegenerative conditions.
  • Autophagy, the process of self-eating, can help clean up the brain and reduce inflammation. Fasting and avoiding sugar can promote autophagy.
  • Conditions like depression, obesity, insulin resistance, and hearing loss are not causal factors but rather associated with weak brain function that can lead to dementia.
  • Building a healthy brain involves providing stable fuel (glucose and ketones), activating the brain through exercise, and ensuring proper nutrition.
  • Neuroplasticity, the brain’s ability to rewire and make new connections, plays a crucial role in maintaining brain health and preventing dementia.
  • Early intervention is crucial in preventing dementia because advanced stages may involve irreversible cell death. Motivation is a significant limitation in working with elderly dementia patients.


Hello Health Champions. Imagine that you wake up in a place that is totally unfamiliar. It’s full of furniture and things that you don’t recognize. It seems like you’ve never been there before and yet you have that disturbing feeling that you should know where you are. And while you’re sitting there, all these strange people come in and start talking and interacting with you as if they’ve known you all your life. Sometimes, these strangers watch you go to the bathroom or take a shower. Of course, it’s only natural now that you feel violated when they invade your personal space. And it’s not so strange that you feel irritable and hostile towards these people. But they all comfort you and reassure you and say that everything will be just fine. And then when all these people finally leave you alone, now you’re left yourself to try to figure out where you are, who these people were, and what it all means.

The sad reality, of course, is that these people are your family and loved ones. In this little story, I was just paraphrasing an actual dementia patient. And dementia is one of the most dreaded conditions of our time. In the UK, they found it was the most feared health condition. And people fear it so much they put off getting a diagnosis. They put off finding out more about it because they feel that if they get a diagnosis, then their life is pretty much over. But we can’t wait. We need to do something right away before it’s too late. And what you need is not a diagnosis. That’s just someone’s label and it doesn’t change anything about how you work or your cells work. What we do need to know is we need to understand some brain basics. We need to understand the mechanisms behind the condition. Like what’s the cause of the damage? What is it that breaks down the brain? As well as what does it take to build a healthy brain? Because those are the two factors that we need to understand.

And what about genetics? Most people think that genetics is the dominant factor, but it turns out that there are a few rare forms, especially the early onset dementia, that have a strong inherited component. But the vast majority of dementia cases, the vast majority, are multifactorial. And that means that even if they have a genetic component, that factor itself is not enough. So even if your relatives had it, if it’s multifactorial, which most of them are, there are many more factors that you can control. And it does not predict whether you’re going to get it or not. And if you can change these risk factors and understand not just what they are, but the mechanism behind them, which we’ll talk about now, you have a chance to slow, stop, or even reverse dementia if it hasn’t gone too far.

The very first thing we have to know is what is the cause. And it’s pretty straightforward. Dementia is caused by damage to or loss of nerve cells and their connections in the brain. But when we look further, it gets really confusing. Common causes of dementia are Alzheimer’s, vascular dementia, Parkinson’s disease, and Lewy bodies. And now we’re getting kind of backwards here. Because dementia is a label, it’s a condition, it’s describing a condition. But so does Alzheimer’s and vascular and Lewy bodies and Parkinson’s. So we have a label that we’re trying to explain by a label, and labels don’t cause other labels. They have nothing to do with the underlying disease process. But when we get it presented like this, we don’t see the way out. We think that this is just something that happens to people when we’re unlucky, and the best we can do is hope it doesn’t happen to me.

Now this article in The Lancet talked about 12 factors that are risk factors, and now we’re taking a huge step forward in figuring out the cause. They found less education, hearing loss, traumatic brain injury or TBI, hypertension or high blood pressure, more than 21 drinks of alcohol in a week, obesity, smoking, depression, social isolation, sedentary lifestyle, diabetes (and it’s not just diabetes, it’s the insulin resistance part of diabetes, so a well-managed type one, for example, does not have that issue), and also air pollution. So what they found is that when these are present, one or more, then that increases the prevalence, the risk of dementia. So if we can undo these, then we reduce dementia. But more importantly, we want to understand what is it about these, what mechanism are they driving or not driving that is causing dementia. And that’s what we’re going to talk about.

First of all, depression and obesity are not risk factors. They are not causal factors. That’s an association. So if we have depression, it’s because there’s something not working quite right, there’s something that’s weak in the brain to balance things out. And that same weakness over time can lead to dementia. So it’s one physiological problem leading to two conditions. It’s not that the conditions are causing each other. And the same thing with insulin resistance, which obesity is typically the result of insulin resistance, and then insulin resistance has a couple of things that causes dementia. It’s not the obesity. They are unrelated.

But now let’s group them together: traumatic brain injury, too much drinking, insulin resistance, air pollution, smoking, and stress. What do they have in common? And there are actually only two mechanisms, really. And the first mechanism is what all of these have in common, and that is neuroinflammation. Inflammation is an immune system response. The body does it on purpose whenever we have tissue damage or infection, or there’s something else the body needs to clean up. In most of the body, that’s done with white blood cells called macrophages. That just means big eater. And we have those in the central nervous system as well, except they have a different name, called microglia. Because everything is different, it’s like this whole different world, it’s a separate system inside the brain and central nervous system. There’s a blood-brain barrier that keeps things separate.

One of the most common things that people don’t think much about is a TBI, traumatic brain injury. And this could be a severe fall, you hit your head, you lose consciousness. But it could be a lot less also. It could be one of the most common ones are in football when people have helmets but they hit their head a lot. They think they’re safe because they don’t crack their skull, but the brain is sloshing around inside the skull, and we’re getting small concussions repeatedly. Another thing is alcohol can create neural inflammation, stress can create neural inflammation, and pretty much any gut issue can create neural inflammation because we have one barrier in the gut, and we have one barrier in the brain. And for the most part, when one is compromised, like a leaky gut, we also get a leaky brain. So whatever is creating inflammation in the digestive tract is also going to create inflammation in the brain.

But now is where it gets even worse. Unfortunately, these microglia can be subject to something called priming. And priming is another word for persistent activation. So it’s like any other immune response that your body remembers. So if you have one concussion and you increase inflammation and microglial activity, then over time, that activity and that inflammation will come back to a baseline. But if you have another concussion, if you have another trauma before it is resettled, now it’s going to redouble its effort, it’s going to increase its activity, it’s going to go to a higher level before. And it’s going to be very trigger happy. And if you do that a third time or a fourth time, now we get pretty much persistent activation.

But it doesn’t even stop there because all these factors can activate these microglia. So let’s say that you had two or three concussions, and then you go have a drink or you end up with a leaky gut, or you have a food allergy, now you could actually have bread with gluten, and you could essentially re-concuss your brain. It’s like you had another concussion, even though you didn’t hit your head, you just triggered another way to activate microglia and inflammation.

Now, a problem is that while most of the body is really good at balancing out inflammation and healing trauma, the brain is not good at all. That’s because the brain is protected. It’s not supposed to get hurt. So when it does, the brain basically just has this weak little reserve cleanup crew. And one way, though, that we can help this process along is something called autophagy. That means self-eating. And it’s been talked about a lot in relation to fasting because when you fast, you don’t put in so much fuel and resources in the body, and then resources become precious. And the body upregulates this autophagy, this self-eating. So it’s like a recycling process. If you don’t eat protein, then the body goes out into the tissues to look for it. And this is one of the most powerful ways to clean up your brain, to speed up this cleanup process, and resolve that inflammation.

So what that means then is that if you hit your head, one of the best things that you can do is to do some fasting or at least to avoid sugar. If you’re in a football game and you hit your head, the worst thing you can do is to go have a soda afterwards because sugar and carbohydrates trigger insulin, which is one of the most powerful ways to turn off autophagy completely.

Now let’s look at the second factor. So the first one was neuroinflammation. What’s the second one? And that relates to less education, hearing loss, hypertension, social isolation, sedentary lifestyle, insulin resistance, decreased nutrients deficiencies, smoking, and stress. What do these have in common? And what is the mechanism whereby they promote dementia? Well, all of them deprive the brain of something it needs to have. So, if we have less education or we have any of these, then we basically get a weak brain. We don’t develop the brain, the strength of the brain, the endurance of the brain to the point where it’s supposed to be. We get a poorly wired brain, and then it’s also underdeveloped. And with all of this, that brain has a lower threshold for trauma, for endurance, for activity, and it’s much more prone to degeneration. And if all these things deprive the brain of something, then next we have to understand what is it the brain needs.

Number one is fuel. The brain is 2 percent of your body weight, and it uses 20 to 25 percent of all the calories, all the energy, all the fuel in your body. And even more important than high or low fuel is stable fuel. Because the brain uses so much energy, it can’t be on sometimes and off sometimes. It has to have a steady energy supply. And that supply is glucose and ketones. Traditionally, we’re being told that glucose is the only fuel for the brain. But that’s not true. Because when we’re fasting, then as much as 75 percent of the fuel can come from ketones. And in our modern lifestyle with way too much sugar and carbs, then we’re probably relying almost 100 percent on glucose for brain fuel. But historically, it’s probably been more like 50-50 between ketones and glucose. And if you’ve ever tried to make a fire, you know that there is no fire, there’s no heat or energy without oxygen. The second thing your brain needs is activation. And this is the most misunderstood. People get it, they need fuel, they need all these different things, but activation is the key. Because you have all these cells in your body, but they all serve a purpose. And if you don’t use them for anything, then your body doesn’t need the fuel, it doesn’t need that cell at all. So the only reason we need fuel is to perform work. And that’s where the activation comes in. Use it or lose it. To build a strong brain, we also need some catalysts to wire the brain properly. That’s brain-derived neurotrophic factor and human growth hormone. So don’t worry about the name, just think of them as miracle grow for the roots and the pathways and the networks in your brain. And then, of course, over time, we’re going to need to replace some of the parts of the brain that wear out, all the tissues wear out, all the molecules wear out. So we need to replace the building blocks. And those are primarily the things that we’re missing most often: DHA (docosahexaenoic acid), which is just the long complex fish oil, and amino acids, which come from protein, and cholesterol, which the body makes but we’re taking all these drugs to keep it down and we’re trying to limit it in the diet, which may not be a great idea. And if all these factors are present, now we can start to build a better brain.

And how do we do that? You have about a hundred billion brain cells. Each brain cell makes on average five to ten thousand connections to other cells. And these connections, called synapses, that’s how the cells talk to each other. Then there’s the concept of neuroplasticity, which means the brain is never the same. It’s not like a statue, it’s not solid. It’s more like a river. It’s constantly changing and modifying itself to fit your environment. As you have new experiences, the brain rewires itself. It’s going to disconnect some of these synapses and make new ones. And Hebb’s law says that cells that fire together wire together. So as you have these different impulses, as you think something, as you have an emotional reaction, as you’re practicing a physical skill, all of these experiences trigger brain cells at the same time. And if they trigger at the same time, then they wire together. You get these experiences hardwired into your nervous system, into your brain. And that is the only way that we can learn things. And over time, we develop a lot of complex automated skills. We have physical skills like balance and coordination. We have cognitive skills like speaking different languages or having an analytical capacity. But how does all of that relate to dementia?

Well, the better we can build these networks, the more complex networks we have, the more complex skill, the more we use them, then the more interconnected they become. The more different brain cells get hooked up with more of the other brain cells. And then we increase the neuronal stability. We increase the endurance and the health of each brain cell. Because a brain cell that sits by itself in a corner somewhere and doesn’t talk, doesn’t connect it to anybody else, it’s not going to fire off very often. It’s going to be a rare occasion. And that brain cell is going to degenerate. But if a brain cell is well-connected, if it’s got thousands or tens of thousands of connections, there’s always going to be some message coming or going. There’s always going to be some activity. So that’s going to increase the baseline activity of the whole network. They reinforce each other. And when that happens, we decrease the chances of degeneration and dementia. We’re maintaining the health and the metabolic thresholds and capacity and endurance of that brain.

Here are the main limitations of working with dementia. A brain cell is like any other cell. It can grow, it can shrink, it can get stronger or weaker. However, once it’s dead, it’s dead. And that’s the problem with the later stages, with the more progressed stages of dementia, that once it gets really bad, there’s a lot of cells that are dead and gone, and they’re not coming back. So we need to catch it early. We need to do something while the cells are not dead but simply weak. And when they’re weak but still there, now we can work with them through these principles we talked about, and we can resuscitate them, basically. Not only that, but we can also rewire and compensate for some of the cells that are dead. If there’s too much of a percentage, we’re sort of past the threshold. But people with strokes, for example, they can have large portions of the brain die completely, and they can rewire and teach other parts of the brain to do the same thing. So we can do that also with dementia to a point. But we have to reverse the process.

So if you are extremely motivated, then there’s tremendous potential. You could do a lot to reverse all these different processes. But therein lies the problem. This is the biggest limitation of working with dementia people, is that they have no motivation. The processes that cause dementia are the same processes that break down the brain areas that control motivation. These people, they’re very difficult to motivate, to help them understand why they need to do something. That’s why we want to change early. This is why we don’t wait for symptoms. We work from day one to be as healthy as we can, to build the best brain we can from the beginning. So start before there is a problem, before there’s a symptom. Why not start today?

So let’s pull all of this together and make sense of it. When we want to reverse and/or prevent dementia, it all comes down to just a few principles. All the different risk factors they talked about comes down to use it or lose it, comes down to neuroinflammation, and a little bit to nutrition. Let’s say that you were unfortunate and you had less education. What did that do? Why is that use it or lose it? Well, you never developed that complex network to the degree that you could have. It’s basically a slightly less developed brain. It doesn’t have that endurance. So what do we do about it? Well, it’s never too late to learn. And with the internet, with YouTube, with free courses, with free language apps, there’s no excuse anymore to blame it that you don’t have the education. Because you can learn every day. So increase your mental activity, play cards, do memorization games, play bridge, do crossword puzzles, and learn new things every day.

What about hearing loss? Well, when you have hearing loss, that means that the signal is not going from the hearing mechanism into that area of the brain that’s supposed to receive it. Either the signal’s missing, or the area in the brain is weak or damaged. But either way, use it or lose it. That area of the brain is degenerating because it’s not being activated, it’s not being stimulated. So what do you have to do? You do something physical, you do some exercise to compensate for it. It doesn’t mean that your hearing necessarily is going to come back, but you can send so many signals from other places that they make up for what’s missing.

If you have a sedentary lifestyle, if you sit still, physical inactivity, then realize that 90% of all the signals that stimulate, that activate the brain, that becomes the juice for the brain, come from movement. And when you’re sitting still, you’re just not stimulating that brain. So get up and move.

What about social isolation? Again, less stimulation. We need all kinds of different stimulation. We need emotional, we need physical, we need chemical, we need mental activity of all different kinds. So social isolation is not a great thing. What can you do about it? Join a club, volunteer, go for a walk, talk to people, do something.

Hypertension is actually a cause in itself. It’s not just this thing that can cause strokes and related to cardiovascular disease. When we have hypertension, that high blood pressure is something that the body tries to protect itself from. So the body can change the perfusion, that the blood vessels are supposed to let through oxygen. But if the blood pressure is too high, then less oxygen ends up going through. So we could actually starve the brain for oxygen even though there is higher pressure of the blood.

The number one solution for use it or lose it is called exercise. That’s why I talk about it all the time. It does two things. First of all, it provides 90% of the signals to activate the brain. But more than that, the more intense that exercise is, the more of these hormones, the brain-derived neurotrophic factor, the human growth hormone, remember the miracle grow for the brain, it’s only going to sprout synapses with these two hormones present. And once you exercise, you activate the brain, but you also provide these hormones to make new connections. In one study, they took kids from being C-average students to A-average students doing nothing more than having them run one mile in the morning before school.

Stress is another one of those things that can cause anything because it affects so much. It can cause neuroinflammation, but also stress puts us in a survival place. And when we’re in survival, we’re not very creative. Normally, there’s a good balance between the blood and the brain, between the brain stem and the cortex. But when you have stress, now the blood goes from the cortex to the brain stem because when you’re stressed, when you’re trying to survive, you don’t need to be creative. You’re just trying to get out of there. But it robs the cortex, it robs the thinking part of the brain of oxygen and therefore we rob it of blood flow and energy. The solution I talk about all the time is to meditate because you activate your brain, you lower your stress responses, and you help your body get back to balance.

If you’re drinking more than 21 drinks per week, I would suggest cut back. And if you’re smoking, then stop it altogether. So those are pretty simple solutions. If you have trouble with it, there are support organizations, there are books, there are 12-step programs. Just do what you need to do to deal with that. And if you’ve had some concussions or traumatic brain injury, if you are obese or if you have insulin resistance, then the solution is pretty simple. You can start with an elimination diet to reduce inflammation, but the biggest thing for those three is going to be low carb and high fat and fasting to reduce insulin, to increase autophagy, and then to make sure that you get some good nutrition. The best thing you can do is to make sure that you eat real food. And for the brain, you might want to supplement with a little bit of fish oil as well.

And one more thing that people get totally backwards is the mental activity versus the physical activity because most people put the mental activity first. They think, „I don’t want to get dementia. I want to read things, I want to do crossword puzzles, I want to be active.“ And those are all good things that help increase the complexity of those networks, of that wiring. But you have to do the exercise first. You have to start with exercise because exercise drives 90 percent of the signals that make the brain grow. And they produce all of the hormones, all of the miracle grow that help you learn. You can’t make new connections just by doing the mental activity. It’s going to go so much slower than if you exercise first. This is like the 90% that pushes the fluid through the pipelines, that fills the system, that makes the soil fertile. And then you add the learning and the mental activity, and that’s going to work so much better.

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