Water you talking about? The Simple Science Behind Hydration
Water haters rejoice! In this post we are going to dive into hydration and why plain ol’ water doesn’t cut it when it comes to hydrating properly. So, grab your Gatorade and get ready to learn the benefits of drinking those ~electrolyte beverages.~
How do you know that you’re dehydrated?
Below is a list of the signs and symptoms of dehydration. Keep these in the back of your mind for a rainy day (or, more appropriately, a super hot, sweaty day) and make sure to contact your doctor if these signs/symptoms do not resolve with rehydration.
Dark urine
Decreased skin turgor (your skin is a little more loose)
Dry mouth and/or lips
Headache
Coated, wrinkled tongue
Dry or sunken eyes
Unintentional decrease in weight
Decreased body temperature
(Krause, 1050)
To start, hydration requires three different components:
SODIUM 🧂, GLUCOSE 🧁, & WATER 💦
These are the key electrolytes in this particular scientific pathway.
If you’re curious about electrolytes, what they are, and why they are important...check out my previous blog post here.
Tell me more, this is SO-DIUM interesting!
*knee slap*
We will begin our hydration story with sodium. Glorious sodium. Many of you know sodium as the bad guy, going around and causing heart disease. That couldn’t be further from the truth…if you incorporate it into your diet correctly.
For hydration purposes, sodium is extremely necessary. Plain water alone dilutes the blood, which in turn bulks up the amount of blood that is running through our circulatory system (known as blood volume and seen in the image below).
All of the components in the picture above, combined, make up the blood volume.
The water will essentially mix with the components of the blood, seen above, and push out the solutes. So, essentially, that 90% water will become 99.9% water, depending on how much you consume.
The increase of blood volume causes our kidneys to produce more urine and sweat (I know yall know about salty sweat), and decreases the amount of sodium in the blood at the same time (since you’re sweating and peeing it out).
✨ Fun fact: your body needs a certain amount of sodium in the bloodstream to trigger thirst! So, if you’re depleting it by peeing and sweating and only replacing it with water (which only contain hydrogen + oxygen - hence the nickname H2O), then you might not get thirsty. Or you may continue to be thirsty after drinking water.
If you fail to replenish the sodium you are losing through excessive exercise, this could cause hyponatremia, resulting in lethargy, confusion, seizures, and loss of consciousness.
(Krause, 439).
And that, my friends, is why Gatorade, Liquid IV, Propel, etc. all contain some amounts of sodium. Because they’re not going to be responsible for you drinking their product during exercise and still passing out. Sounds like a lawsuit waiting to happen.
C6H12O6
🧁🍭🍫🍬🍩
or otherwise known as Glucose. Aka everyone’s favorite.
Glucose, aka sugar, is also found in all of those rehydration drinks (read the nutrition label people!) but, why?
Turns out it’s pretty simple.
Glucose is the body’s favorite source of energy and will do anything it can to make sure it absorbed it quickly so it can be processed into ATP (also known as energy).
So, it is readily being absorbed by the intestines. And if you mix water, sodium, and glucose guess what happens? All three get absorbed pretty quickly!
Which is why you almost always see a combination of sodium, glucose, and water in drinks that are promoting hydration.
Now I’m sure some people are thinking “but Marley, I’ve heard Gatorade is bad for you because of the sugar?” And technically that’s not wrong.
Our typical sports drinks contain between 2%-9% glucose, and research has shown that the ideal water to glucose ratio is around 1%-3%. This means that your drink should only be 1%-3% glucose and the rest water. So, the sports drinks that are on the market now contain nearly 2-3x more glucose than is scientifically necessary to properly hydrate.
(Krause, 439-440)
So what should you do? Simple.
Mix about 1/3 of your sports drink with water.
Personally, I don’t do the exact ratios because…math. But diluting any full sugar (not the ‘zero’ version as these only contain artificial sweeteners) sports drink with water will:
1. Cut down on your sugar intake and
2. Properly hydrate you!
And my clients say that it tastes better, too!
If you have any questions about hydration, would like additional information, or just want to chat, you can always contact me here.
Thanks for reading!
Sources
Mahan LK, Raymond JL. Nutrition and Exercise In Sports Performance. In: Krause's Food & the Nutrition Care Process. St. Louis (Mo.): Elsevier; 2016:439-440, 1050
