Eli5: If urine is as warm as your body temperature, then why does it feel much warmer when it comes out of the urinal tract?


Is it because the temperature is much lower in your genitals and your brain registers the difference?

In: 0

Yeah, what you said. Your appendages are a lower temp than your core body temp. Men have a ball sack, to keep spermy bois at a lower temp, for example.

Depending on the environmental temperature, a human body usually feels warm, and the inside of a human body is always warmer than the skin. It physically has to be that way, given that no cooling or heating system (biological or otherwise) is perfectly efficient. Ditto for any bodily fluids.

So your urine is as warm as deep inside your body, which is definitely warmer than your skin, or more external parts of your body. Your bladder and urinary tract do have thermo-receptors (nerves which detect temperature). So you are probably feeling the temperature change from the warmer fluid further inside your body, flowing past these receptors.

Edit: tl;dr yes

If you’re referring to male genitals, the temperature down there is lower than your core temperature. Hence you feel the warmth.