[myabaumbach (OP)]

I know we get liquid from our food intake, as well as our liquid intake, but does the body produce liquid that we also pee out?

I ask because I'm sure I pee much more than I intake :/

[chiralSPO]

First thing's first: matter is conserved, and we can ignore nuclear reactions within the body, so we can say that every atom that goes in eventually has to come out.

Urine is mostly H₂O. And yes, we (should) drink a significant amount of H₂O each day (even if we can't agree on how much is optimal). Food also contains a lot of H₂O (especially fruits and veggies, some of which can be >90% H₂O by mass). But even if you were to consume absolutely no H₂O, it would still be produced by metabolism of carbohydrates, proteins, and fats. The H atoms contained in those molecules can be combined with O atoms from inhaled oxygen to produce H₂O.

That said, your body also loses significant amounts of H₂O by evaporation, both from sweating and from breathing. And feces also contains some H₂O. So urine is not the only exit for H₂O. (I will ignore other bodily fluids for this analysis, but there is some nonzero contribution from those as well).

Finally, urine contains more than just H₂O. It typically also contains urea, uric acid, creatinine, ammonium salts, urochrome, bilirubin, inorganic salts (of sodium, potassium, magnesium, etc. with sulfate, phosphate etc.), as well as other small highly polar or charged molecules that the kidneys filter out like hormone metabolites, drugs or drug metabolites.

[Origin]

I ask because I'm sure I pee much more than I intake

You're mistaken.  Your body loses moisture each time you exhale.  You lose moisture through your skin by sweating.  You lose moisture by peeing.  You take in much more water than you pee out, if you didn't you would dry out and die.

[alancalverd]

BC pointed out in another thread that we pee more in cold weather because the body burns more fuel to keep warm, so produces more water.

A high proportion of our food is water anyway.

So we take in "virtual" water along with actual liquid H2O, therefore excrete by various means more that the volume of liquid water input.

[evan_au]

I'm sure I pee much more than I intake

If you find that you are urinating more often, or in larger volumes, you should discuss that with your doctor.
- Increased urine output is a symptom of diabetes, which is becoming a bit of an epidemic
- Various kidney problems
- (For males) This may be an indication of prostate problems
https://en.wikipedia.org/wiki/Polyuria#Causes
https://en.wikipedia.org/wiki/Benign_prostatic_hyperplasia

[gerardseal]

The more we drink, the more intensive the cleansing processes take place. Water activates metabolic processes and removes all "unnecessary". Therefore, not only water comes out with urea, but also other substances.

[stevenD]

Why do we urinate more than we drink? When you have more particles than fluid, your kidneys hold on to fluid, and you don’t feel the need to pee. Because alcohol is a liquid, it tips the osmolality in favor of more fluid. As a result, you ‘ll ultimately pee out the equivalent of what you drink (assuming your kidneys are working well)...

[JesWade21]

The pituitary gland is inhibited in its production of anti-diuretic hormone by alcohol (ADH). ADH is the hormone that tells your kidneys, "When you're done processing that waste, re-absorb the majority of the water." As a result, water flows directly through your kidneys to your bladder, causing you to pee frequently.

A hangover, by the way, makes you feel bad because your brain is dehydrated. To avoid feeling crappy, drink plenty of water.

[FannieMaloy]

Peeing it out is specifically what we need some of that water for. Your body has a lot of waste chemicals that need to be removed. Those chemicals are water soluble, so you drink water, that water is used to absorb the waste, and that waste is removed from your body through the urethra.