Transcription
Have you ever heard of beta amalloid? It's not a planet the Voyager visits in Star Trek. It's a protein that causes massive issues in our brain. So much so it leads to neurodegeneration like the various forms of dementia, like Alzheimer's disease. Now, our brain slowly dies, and sometimes quite rapidly, relatively speaking. So how can we stop beta amalloid?
Your body actually already does, naturally, using something called the glimpmphatic system. But could dysfunction in your lymphatic system be massively accelerating your risk of Alzheimer's disease? And if so, what can you do to save your brain? I'd like to show you a few studies that answer those questions.
So, you may have heard of this lymphatic system before, and that's the one that, when you're sick, can create enlarged lymph nodes in your neck and arms. But that's not what we're discussing here. We're discussing its sibling system, the glimpmphatic system, which is in our brain. Now, it's an intricate mechanism where cells in your brain create another pipe network around your blood vessels going into our brain. Think of it like a pipe within a pipe. The smaller pipe is your artery or vein, and the larger pipe is part of this lymphatic system. It's made up of cells that extend projections called NFT and create a barrier between your blood and the actual brain cells. The space between the first pipe, so your blood vessel, and the second pipe, the NFT, is called the perivascular space or PVS. This is important to what I'm going to be telling you. So keep the PVS sharply in your mind.
So fluid will travel from the PVS, pass through the NFT, and into the space occupied by the main cells of your brain, like the neurons, the cells that you know actually communicate with one another, allowing us to think, comprehend, breathe, move, and literally everything else that keeps us alive and well. Exactly here is where beta amalloid, a protein secreted by our neurons and other cells, is found. It's here, between all these cells, that beta amalloid aggregates, which means that it clumps up together. Think of them like bogs in the water between cells, disrupting communication between neurons. Fortunately, as I alluded, the liquid that comes from the PVS into this space between the cells will pick up the beta amalloid like a trash service and carry it out of the brain, going back through the PVS on the outflow side. This is as literal a brain cleaning as we can get. And I have to pause here to ask you, how freaking cool is that? So, in simple terms, the fluid in your brain washes away beta amalloid through this perivascular plumbing system. That's the main point.
Knowing that, what happens when these perivascular spaces are stressed or disrupted somehow? For that, when we lean on studies that try to investigate that question. When we, I mean scientists, humanity as a whole, look at the relationship of damaged or dysfunctional perivascular space, meaning that there's not as tight of a barrier between the NFT, or there's a buildup of proteins like amalloid that can't be cleared out, or the veins have stiffened, or any number of other reasons. The point being, they're not functioning like they should. So, what happens when we stratify people based on clinically independently repeatedly assessed PVS health? So, stage one being the healthiest, up to stage four being the most disrupted. We can see that what happens here. The vertical axis is the risk of dementia. So that's the brain disorder. So the higher up, the better you are dementia-free. The horizontal axis is the time that these people have been tracked and measured. Each category with four being the worst PVS health is listed, and then there are three graphs. Those correspond to the different regions of the brain. Now, I'm not going to complicate that aspect. The main thing that you should see here is that if the lines go down faster, there's increased risk of dementia. And certainly in the extremes, but largely in a step-wise fashion, the worse your PVS health, the greater the risk of dementia. So the point here being that if your perivascular space is disrupted somehow, there's a greater risk of developing dementia like Alzheimer's disease. Now, in fact, by some measures, as much as a 400% increased risk. So something to really take seriously.
Okay, fair enough. We see this association, and the researchers did adjust for a variety of other factors that could account for this association. Now, why exactly do we see this relationship to dementia? On one hand, it might seem obvious, considering that we've been over what we just went over with the beta amalloid situation, but it's really not that simple. For one, we can certainly turn to other studies like these, where the direct relationship between the lymphatic system and beta amalloid plaque is assessed. These studies, looking at imaging of the brain, are able to tease out if amalloid plaques are being evacuated from the brain effectively. Essentially, they show that a better-functioning lymphatic system is linked to reduced beta amalloid in the brain. And when looking at Alzheimer's disease risk, as opposed to all dementia risk, remember Alzheimer's is a specific disease within the umbrella of dementia, we see a concerning trend. The vertical axis indicates an index of lymphatic function. The higher the better. So the three conditions listed are cognitively normal individuals, mild cognitive impairment, and Alzheimer's disease. When we compare, there seems to be an almost a step-wise link between lower lymphatic function and worse brain health, especially with Alzheimer's disease.
But more telling, and counterintuitively possibly, not all dementia-related proteins like beta amalloid show a relationship with worse glimpmphatic function. For example, another implicated protein in Alzheimer's disease is tau protein. The reason this might not track with lymphatic function is because tau is an intracellular protein. It's found inside the cells and can't be washed away like beta amalloid. Ultimately, the takeaway here is that lymphatic function is related to beta amalloid accumulation and Alzheimer's disease. However, there are ways of improving lymphatic function. This isn't like a foregone conclusion that you will develop Alzheimer's right on schedule. I'd like to detail some of those factors and some of the studies showing what we can do to improve dementia risk, including Alzheimer's disease. One of those factors is sleep, of course, and I'll be getting into that in just a minute. But in addition to that, there's a fascinating study on sleeping position and its impact on the lymphatic system. Now, I'm covering that in the extended version of this video that you're watching, as well as some of the more details on each of the studies that we've covered up to this point. If you're interested in checking it out, then check out the Physiotic Insiders membership. It comes with articles for all my videos if you prefer to read, plus simple summaries for highlights, plus all these perks right here, like the private podcast, live sessions, the community, and more. Anyway, if you're interested in complete access, check it out. Link is in the description.
So, what can be done to prevent dementia and support our lymphatic system? Well, one clinical trial aimed to find out if we can have a measurable impact through lifestyle modification. So, when lifestyle modification was implemented over two years, people in their 60s and 70s experienced improvements in their cognitive ability. The higher the lines go, the better their cognitive function. The red line is the people using lifestyle improvements. So, what kind of lifestyle interventions are we talking about here? Well, four pillars. Here they are. One, nutrition. So focused on fruits and vegetables, but also including some dairy and meat, and eating fish twice per week. So think of it similar, but maybe not identical, to a Mediterranean-style diet. Two, exercise. So including strength training one to three times per week, plus two to five times per week of endurance training. Three, cognitive training. So using a computer-based training like puzzles, memory tasks for only 10 to 15 minutes per day, and even just like three times per week. Four, vascular risk management. Getting regular blood tests for cholesterol, blood sugar, testing your blood pressure, weight, and generally keeping an eye on vascular dementia-related biomarkers, which are the ones we just went over. So yes, a well-balanced lifestyle directly improves brain function, though we don't know if this targets the lymphatic system directly.
So what evidence is there of direct targeting? The answer is sleep. There are some big influential studies and some corroborative evidence in humans that sleep is probably the biggest player in maintaining low amalloid plaque levels and supporting the lymphatic system. Importantly, the quality of the sleep matters, and the stages of sleep. For example, getting deep sleep, also known as slow-wave sleep, has been shown to have a specific drastic effect at improving lymphatic drainage. One quick tip that pops up in the research, though I'd like to make some more specific content on this, is the temperature. If your environmental, so your bedroom temperature is between 19 and 21 degrees Celsius, that's about like 66 and 70 in Fahrenheit, it promotes more deep sleep and generally better high-quality sleep as a whole.
So all this considered, where does this land us? Well, for one, while we've been going over studies relating lymphatic function to Alzheimer's disease, there's more research that's needed to really nail down the causative connection. But based on what we have now, there's certainly a relationship there. And mechanistically, it does make sense. You can reduce your risk of dementia as a whole by improving your nutrition, regular exercise, mental training, and keeping a regular eye on your risk factors for vascular dementia, like blood pressure and cholesterol levels, to just name two. Otherwise, for targeting the lymphatic system directly, and likely all forms of dementia, including Alzheimer's disease, focus on sleep. It is among the most important factors. So, sleep length is one aspect, trying to get at least seven hours. Then sleep quality by sleeping through the night as well as possible, but also entering slow-wave sleep or deep sleep. That's helped by things like room temperature, keeping your room between 19 and 21 degrees Celsius, that's 66 to around 70 degrees Fahrenheit. And there are many factors that come into play for Alzheimer's and dementia altogether. If you're interested in a more complete story beyond the glimpmphatic system, check this video out. Thanks for tuning in. I'll catch you in the next one.