Curious, what kind of damage does holding your pee do or could do?
It can cause urinary tract infection, and I believe (not 100% sure) kidney stones.
brb, gotta go wee real quick
Holding in your pee for long durations causes the muscle to stop working normally. I went hours and hours at times holding it and developed two problems, and it's taken a decade to retrain it to work normally again
One: my urethral tract widened out such that it only empties fully if I press on my taint/prostate area. If I forget to do this, I have to deal with moist undies. Doctor told me it's because it would slowly fill with urine after my bladder became too full, though there's another "valve" further along the tract that still held it in. It acted like a second bladder almost, and probably would hold almost 30ml on my worst days.
Two: if I held my pee too long, even an hour if it's urgent, the muscle sort of weakened or something over time and it would instead slowly leak. Apparently it's what our muscles do naturally to relieve pressure on the bladder, which absolutely has to empty regularly since the body needs to avoid ketosis by having the kidneys constantly working. The muscles say "well, gotta still make urine to avoid dying, so we'll dribble it out a drop at a time instead" and the more often this happens, the more often they'll default to the slow leak option
These days it's much better, I literally spent 10 years of my life exercising good bathroom habits as best as I could to retrain the muscle that's in the prostate. Nowadays I rarely have an issue but if I were to go to sleep while needing to urinate and refusing it, I'll wake up the next morning with ever so slightly damp underwear.
TL;DR Pee when you need to, not when you want to, or you'll end up peeing when you don't want to more and more often.
Edit: I will add that I had at one point a very persistent and very painful (sometimes odorous) urinary tract infection that wouldnt go away for a year or so as well. It was terrible. 0/10 would not go through it again.
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