Nutrition Myths


Dehydration is the process where body water is lost. (1)

It usually occurs as a result of excessive sweating (often when during physical exercise there is not enough fluid intake), vomiting, diarrhea and diuretics. (2)

The following are progressive signs of dehydration with increased water loss. REF (Adolph EF. Physiology of Man in the Desert: Heat Exchanges, Sweat Formation, and Water Turnover. Hafner Publishing Co Ltd; New impression edition, 1969. 33-43.)

Fluid loss at:

  • 1% of body weight: thermoregulation is impaired and the first signs of thirst occurs;
  • 2% of body weight: thirst increases, vague discomfort sets in and appetite decreases;
  • 3% of body weight: dry mouth;
  • 4% of body weight: work capacity decreases by 20-30%;
  • 5% of body weight: difficulty in concentrating, headache and sleepiness;
  • 6% of body weight: tingling sensation, numbness of hands and feet;
  • 7% of body weight: possibility of collapse;
  • 10% of body weight: life threatening;

Dehydration usually doesn’t occur in healthy people in normal circumstances.

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