Re: drinking slightly older urine

"Yes, I know that this is the commonly accepted wisdom. It still doesn't answer the question: if urine has antibacterial properties, as is also commonly accepted, then why doesn't this neutralize any bacteria growing after 15 min?"

I believe you are mixing apples and oranges.  You are confusing sterility with antibacterial properties.  While urine is sterile, it is not antibacterial.  Distilled water is sterile too but left in the open for 15 minutes it will also attract bacteria which in time will cause it to become un-drinkable.

The urinary tract can become infected and the urine passing through that tract does not heal the infection.  (Talk to a female who has had one of those infections and they can be difficult to cure.  Females tend to get more of these infections than males.  They will often drink cranberry juice to kill their infection and a woman friend of mine found that to work very well.)  One can also get bladder infections (had one as a child) and urine in the bladder does not kill that bladder infection either.  If you drink your urine during either of these two infections you are also drinking the bacteria that is causing the infections.

You say that you drink your urine at night.  Many folks find that drinking pee in the evenings blocks their ability to sleep.  I have found that I can't drink mine after 4 pm at the very latest without it keeping me awake so end that activity by 2 pm at the latest.