When I was diagnosed with type 1 diabetes, my primary symptom was thirst. Sure, there was some blurry vision and frequent urination, but I was able to brush those aside, thinking that the urination was (duh) a result of the excessive amounts of fluid I was drinking and  as for blurry vision, well, maybe it was finally time to need glasses. But the extreme thirst was unusual and difficult to ignore, and as much as I loved my Nalgene bottle (old school style, the gray bottle with the blue cap – it was 2001 after all), refilling it was getting annoying.

From what I’ve heard, this is common in many people’s diagnosis stories. But I never stopped to ask why – until today. Today I did ask, and here’s what I found:

One of the many jobs of the kidneys is to extract glucose from the fluid you consume, sorting some of the fluid out to become urine and putting the glucose back into the blood stream where it will be processed by that lovely little hormone called insulin. When blood glucose levels rise to a certain level, the kidneys get overwhelmed and can’t pull the glucose out as efficiently. So, in a sense, you start to pee sweeter. (Awww, isn’t that a cute way to say it? No? Right – it’s gross. I can’t argue with you there.)

But that’s not the end of the thirst-inducing ramifications of high blood glucose.

Your body can recognize when there’s a lot of weirdness happening in your kidneys, so it tries to flush it out by producing – you guessed it – even more urine. The body draws fluids from your bloodstream and tissues to help get rid of the extra-sugary weirdness, and in doing so dehydrates itself even further.

As a result, you get so thirsty, you consider buying stock in Big Gulp and petitioning for Starbucks to go beyond the disgustingly huge trente size…. Sound familiar?

So there you go, now you know what is happening in your body to cause that I-could-drink-the-entire-ocean thirst you might have had when you were diagnosed. And it might come back from time to time when your blood glucose runs high. When this happens to me, I do get thirsty, but not to the point where I obsess over when I can fill up my water bottle again, or whether or not it would be appropriate to wear a camelbak apparatus to a business meeting. I just get the simple kind of thirsty – but everyone and everyone’s diabetes is different.

Fun fact #1: Excessive thirst, when presented as a medical symptom, is called “polydipsia” – which just sounds funny to me.

Fun fact #2: It’s really difficult to write about thirst without feeling… thirsty.