It’s one of those questions that a lot of you have asked: why do I shiver when I pee?
If you haven’t experienced this, you’re probably wondering if it’s even a real thing,
or if it’s just some big practical joke online.
I don’t blame you, because urinating and shivering don’t seem that closely related.
Well, it turns out that shivering after you pee is something a lot of people seem to
experience, and it seems to affect males more than females.
But … nobody really knows why it happens.
There actually hasn’t been any peer-reviewed research on it.
Now, we’re not the first ones on the internet to try to answer this question.
If you look around, you’ll find plenty of articles giving a few possible explanations.
Here’s the thing, though: lots of those articles are wrong.
They seem to be getting their information from a letter-response article written in
1994, which /itself/ was based on a discussion about pee shivers a bunch of people were having
in a forum — not exactly a legitimate scientific source.
So you might’ve heard people say that these shivers happen because your body temperature
suddenly lowers after you lose all that warm urine.
But that idea just comes from the discussion forum, and it doesn’t really make sense
anyway — you don’t shiver when you vomit, even though that’s also a case where you’re
losing a lot of warm fluid.
Even the supposedly-official scientific name for the phenomenon, post-micturition convulsion
syndrome, was made up by someone in that forum.
So, remember to check the sources before you believe things online.
When journalists have asked excretory system experts about this, they kind of have an explanation:
the shivers might have to do with an interaction between two different parts of your nervous
system.
When you choose to start urinating, your body also lowers your blood pressure.
That’s the parasympathetic nervous system at work — the part responsible for involuntary
processes that are more about resting, like digestion and lowering your heart rate.
But peeing also triggers the sympathetic nervous system, which is involved in other involuntary
processes like the fight-or-flight response.
It’s possible that you get the pee shivers when there’s an especially strong interaction
between these two responses.
That would explain why this seems to affect males more than females — when you stand
up to pee, your blood pressure will be slightly lower than if you’re sitting, which could
lead to a stronger interaction between the two parts of the nervous system.
But again, there’s no research on this, so it’s hard to know for sure.
So get on this, scientists!
The world wants to know!
Thanks to all of you who’ve asked us this question over the years, and thanks especially
to all of our patrons on Patreon who keep these answers coming.
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