You can't use thirst as an accurate measure of how hydrated you are. 

I said it once, and I'll say it a million more times.  

Hello there, it's me, Dr. Kelly Sadauckas, Pelvic Floor Expert and Double Board Certified Internet Sensation here to debunk some rumors that have been flying around about how "you can't be dehydrated because you're not thirsty."  

Sorry to be a spoilsport, Matilda, but thirst is a TERRIBLE predictor of hydration status, and can pretty much NEVER be trusted to tell you if you're hydrated or not.  

Ready to learn more?  Let's dive in.

3 Reasons You Can't Use Thirst As An Accurate Predictor of How Hydrated You Are

1. If You Are Dehydrated, The Brain Turns DOWN The Thirst Reflex, to Allow You to Focus Energy on Finding Water...

Your brain is SUPER SMART. Smarter than you realize.  Like scary smart.  It is constantly receiving information.  And one of most critical pieces of information it processes each day, is how much clean water is available to us, at any given time. 

This makes sense, because without clean water, the human body will die within 3-4 days. 

So it's important you find water...and if you were lost in the desert, and didn't have water, your brain doesn't want you wasting time thinking about how thirsty you are.  

So whether we don't have access to clean water, OR WE SIMPLY CHOOSE TO NOT DRINK ENOUGH WATER, the brain now assumes that adequate water IS NOT available...even if it IS available in gallons from the faucet.

The brain assumes that water is NOT available, however, and turns our thirst reflex down, so that evolutionarily, we can free up our energy to "find the water source", and "guzzle down the water in large amounts", as we are certain to do, once we find it again, because any human would be out of their mind to have access to clean water and not drink their fill of it.  

Paradoxically, if you start the day by drinking 1-2 (or even 3) glasses of water, the brain recognizes that fresh water is indeed available, and the thirst reflex will be activated and normalized, and then "useful" for that day, as long as you are not ridiculously dehydrated.  

So when someone says "I'm just not thirsty enough to drink more water" to me...

I stare at them silently... ... ...for just long enough to make them uncomfortable... I then ask them if they want their pain to go away?  ...or their cognition to improve?  ...or their pee or poop problem to get better?  

Generally, the answer is yes.  And generally that won't happen unless they drink more water.  

2. Your Brain is 80% Water!  If you are chronically dehydrated, you can mess up how it functions and your "thirst and quenching reflexes" can actually get messed up for a while!

This is a bit more complicated, but let's just say that your brain is a bit more complicated than a simple light switch.  And it runs on all sorts of different plugs and connections, and relies on all sorts of chemicals being in the right place, at the right time, with the right amount of water.  And if the water is thrown off for long enough...and the chemicals are thrown off for long enough...or the gut is inflamed for long enough, so that inflammatory molecules get into the blood and past the blood brain barrier, your thirst and quenching (satisfaction) reflexes are going to be what is scientifically known as wonky.  

Essentially, you can no longer be trusted to make good decisions, and you end up drinking 3 liters of diet soda a day, 7 days a week, and wonder why you "can't stand the taste of water anymore," and "how anyone can even drink water, it's so gross."

For you, my friend, it is time for an intervention.  Your body literally requires a detox, and my friends at Gunderson Medicine, or Wydaho Integrative Wellness can help you revamp your nutritional profile :). 

3. Cold Water will "Turn Off" Thirst Receptors Quicker Than Room Temperature Water

This cool study (in rats) from 2016 was really interesting.  It showed that cold water turned off thirst receptors (mice stopped drinking) faster than room temperature water.  

Take home from this is that If you are having a hard time getting/staying hydrated, you should drink room temperature to WARM water, as you will be able to drink MORE of it before feeling full or satiated.   This is ESPECIALLY important if you have a "history of not drinking water", "don't like water" or "aren't thirsty".  

And since cold water can "turn off thirst" faster than warm water, that's another reason thirst can't be trusted.  

So if thirst can't be trusted, how do I know if I'm hydrated? 

Great question.  Here's the top ways to know if you're hydrated: 

1. Know Your Hydration Numbers

To find your baseline fluid intake, take your body weight in pounds, and divide this by 2.  This is your baseline target for fluid ounces, 75% of which should be non-caffeinated and non-alcoholic.  Add 8 oz per 2000 ft above sea level you live at, another 8oz if you're breast feeding, and another 8oz for each hour you spend exercising a day, and NOW you have your baseline fluid ounces.  

2. Now, track your intake!

I garuntee, unless you are tracking intake occasionally, that you actually have NO IDEA what you are taking in.  Join our mailing list via the link below, and we'll guide you in a 3-day bladder diary, to get you a baseline of how you're doing from a fluid perspective.  

If you're close to your target, HOORAY!

If not--set a reasonable goal, and work on it!  Dr. Kelly's favorite tip is to try to drink 1/3 of your target fluids by breakfast, another 1/3 by lunch, and a final 1/3 by dinner. And yes, you should be able to do this and NOT pee your pants.  I see you, Margaret.  

PSA, each of Pelvic Floored's Online Courses works with you on this, and specific goal setting, with education as to why the hydration matters for that specific course.  

3. Also, look at your pee!

Is your pee a dark orange?  Not hydrated.

Bloody?  Go to the Urgent Care.

Light yellow?  Doing GREAT!

Cloudy?  Monitor, and go to urgent care or walk in clinic for UTI test if it persists, or is accompanied by a fever, cognitive change, or pain in your pelvis or "down there" parts.  It could be an infection. 

TOTALLY clear?  You could be hyper hydrated.  Be sure to include electrolytes with your fluid.  Know your above numbers, and be sure you're not getting "TOO MUCH" water.  It IS possible to dilute your blood stream and urine, and diluting the urine is fine...but dilating the blood stream can lead to heart attacks, which you do not want to do.  

These are the reasons why you cannot trust thirst as a predictor of hydration status, and some ideas for what you can do to ensure appropriate hydration instead.  

I hope this was helpful.  Hydration is super important for happy pelvises, happy brains and happy ever-afters.  Please comment below if you nave thoughts on hydration, favorite electrolyte powders, or other topics you want to see in the blog!  Thanks for being here!

Until next time,

XOXO

Dr. Kelly 💋

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