The human organism requires sufficient fluid in order to function.
Dietitians recommend a daily fluid consumption of 1.5 – 2.5 liter for healthy adults in normal living conditions.
However, fluid requirements increase significantly in hot weather, under physical stress and when sweating, for instance during sports. Three liters or more a day can be necessary then. There are also situations in everyday life that necessitate an increased fluid intake. Dry office air for instance increases fluid requirements twofold.
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