Every day you lose water through your breath, perspiration, urine and bowel movements.
The National Academies of Sciences, Engineering, and Medicine determined that adequate daily fluid intake is:
About 15.5 cups (3.7 liters) of fluids for men
About 11.5 cups (2.7 liters) of fluids a day for women
These recommendations cover fluids from water, other beverages and food. About 20 percent of daily fluid intake usually comes from food and the rest from drinks.
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