H2O

We lose 2,5 liters of water daily. 1,5 l through the kidneys, 0,3 l through the colon, 0,2 l through the lungs and last but not least, 0,5 l through our skin. That's why we need to replace at least 2 liters of water every day.

The first place that water is lost is in the lining of the stomach.