That Neuroscience Guy - Neuroscience Bites-Dehydration

Episode Date: March 2, 2023

In today's Neuroscience Bite, we discuss what happens to your brain when you're dehydrated. 

Hi, my name is Olaf Kregolsen, and I'm a neuroscientist at the University of Victoria. And in my spare time, I'm that neuroscience guy. Welcome to another neuroscience bite. So again, this is a request from a listener, dehydration and the brain. Because it's a bite, I'll keep it short and sweet. But remember, at that neuroscience guy, you can send me a listener, dehydration and the brain. Because it's a bite, I'll keep it short and sweet. But remember, at that NeuroSci guy, you can send me a message. We're taking ideas to wrap up season four and also to start filling out season five. So we know that hydration is crucial for overall brain health. All right. And we know that dehydration is bad for brain health people don't know the exact numbers but you only need to be one percent dehydrated to experience about a five percent loss in cognitive

function now that is uh you know those numbers aren't exactly exact you know other sources would tell you different things but what we do know to be true is that a 2% loss in brain hydration can result in things like short-term memory loss and you can have trouble with math. And actually, if you have prolonged dehydration, it can actually change the cortical tissue throughout the brain. And if you think of the aging question, this is a really interesting one because we know that people above the age of 65 tend to be dehydrated. They simply don't drink enough water. Any number of factors could keep them up at night, could be difficult to do. But we do know that as people get older, there's changes in brain mass and size.

And people are now hypothesizing that this could be one of the mechanisms. There's other mechanisms why this occurs, but I find it really interesting myself that we know that elderly people are dehydrated. We know that being dehydrated can result in a loss of cognitive function. So there's other problems with dehydration in terms of the brain as well. Depression, all right? Afternoon fatigue, sleep issues if you're dehydrated, inability to focus. Some people talk about mental clarity. And it's important to be hydrated because basically about 85% of the brain is water. Like if you break down all the tissue and see what it's really made up of.

85% of the brain is water. Like if you break down all the tissue and see what it's really made up of. So it's an important part of the brain, obviously, but how specifically? Well, one is it's part of the energy process, all right? You basically need energy or water, sorry, to produce the energy for the brain to function. We also know that water is a part of the process where you produce hormones and neurotransmitters. And basically, because the brain can't store water, and we're constantly losing water, it's essential to continuously dehydrate. So in terms of what happens if you're dehydrated, you've got this loss of cognitive function. You can also get symptoms such as depression, fatigue,

and sleep issues. The mechanism is that literally water is needed to produce energy for neurons to fire. It's also necessary for the production of hormones and neurotransmitters. And because this is a bite, I'll keep it quick. But some tips to stay hydrated. Well, the simple one is drink a lot of water. You know, I carry a water bottle everywhere I go.

I'm not saying I'm perfect at it, but you got to drink a lot of water and set up a schedule or something like that. The recommendations vary, but you need at least two liters a day. And some people say more than that. So you just have to increase water consumption any way you can. The only tip I'll give you, because I've struggled with this one, is I sort of cut off the water just after dinner because, well, I don't have to give you the details of my personal life. But let's just say, if you drink too much water later in the day, you might find yourself waking up at night. Anyway, there's dehydration in the brain, another bite. Remember, there's the website,

you can check it out, thatneuroscienceguy.com. It's got links to some stuff. DM me ideas. Again, this is another idea that came to me on Twitter at that neuroscience guy. And of course, please subscribe to the podcast. And thank you so much for listening. My name is Olof Kreg Olsson, and I'm that neuroscience guy. I'll see you on Sunday for another full episode of the podcast.