How to calculate the amount of water a person loses in a day

       

This calculator can accurately estimate the amount of water a person loses per day.
Use it as a guide to the amount of fluid intake needed to prevent dehydration and heat stroke in your own environment, as well as kidney and heart problems associated with dehydration.
FYI：National Institute of Biomedical Innovation, Health and Nutrition

important point

The following are some notes on the calculation results.

”It is important to note that even if a male in his 20s loses an average of 4.2 liters of water per day, he does not need to drink 4.2 liters of water per day.
There is about 10% (about 0.4 liters) of water produced by the body in the process of energy metabolism, and a little water also enters the body from exhalation and other sources. Therefore, about 85% of this amount (about 3.6 liters) is the standard water intake.
Furthermore, many foods contain water, so simply eating a "solid diet" will result in a significant water intake.
In the case of a Japanese person eating three typical meals, about half of the 3.6 liters of water is consumed from food, and the amount needed for "hydration as liquid" is about 1.8 liters per day.
For a woman in her 20s, this is about 1.4 liters per day.”
Source: National Institute of Biomedical Innovation, Health and Nutrition

The above calculator is based on the following formula