Answer to Question 1
In 2004, the Institute of Medicine suggested that women consume 11 cups of water per day (2.7 liters) and men, 16 cups (3.7 liters). This amount includes water from all beverages and food consumed. About 80 of our total water intake comes from beverages and 20 comes from foods, so women and men need to drink about 2.2 and 3.0 L per day, respectively. In contrast to previous recommendations, the committee concluded that caffeinated beverages such as coffee and cola contribute to total water intake to the same degree as noncaffeinated fluids.
Answer to Question 2
The body is least tolerant of water loss. Lack of sufficient water is called dehydration or hypohydration and can lead to serious consequences. Just 2 water loss will decrease cognitive function, motor control and ability, short-term and long-term memory, attention span, and ability to maintain core temperature (especially when exercising), and increase urinary tract infections and fatigue. One needs to pay particular attention to at-risk populations such as infants, children, the elderly, and athletes.
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