The human body contains from 55% to 78% water, depending on body size.
To function properly, the body requires between one and seven liters of
water per day to avoid dehydration; the precise amount depends on the
level of activity, temperature, humidity, and other factors. Most of
this is ingested through foods or beverages other than drinking straight
water. Studies have shown that extra water intake, especially up to 500
milliliters at mealtime was associated with weight loss.
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