Article
Thirst and fluid intake following graded hypohydration levels in humans

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Abstract

The relationship among changes in thirst sensations, blood variables, and differential fluid intake in hypohydrated humans was examined. Seven subjects were hypohydrated by 0%, 3%, 5%, and 7% of their body weight on four separate trials which were systematically randomized between subjects. Hyphohydration levels were achieved with a regimen of restricted food and fluid intake and moderate heat-exercise stress. Statistically significant linear and quadratic trends were found for the intensity of several sensations with progressive hypohydration levels. In general, plasma osmolality and renin activity increased and plasma volume decreased with increasing hypohydration levels. During a one hour period of ad lib drinking, all subjects consumed insufficient fluid to rehydrate back to baseline body weights. Using regression analyses, fluid intake was predicted by the magnitude of subjective and physiological indices of hypohydration. Results demonstrate that both hypovolemia and plasma osmolality contribute significantly to fluid intake in hypohydrated humans. The results also indicate that thirst sensations make a substantial contribution to differential fluid intake in humans.

References (28)

  • S. Ramsauer et al.

    Effects of water temperature on the reward value and satiating capacity of water in water deprived rats

    Behav Biol

    (1974)
  • B.L. Sandick et al.

    Perception of drinking water temperature and effects for humans after exercise

    Physiol Behav

    (1984)
  • E.F. Adolph

    Signs and symptoms of desert dehydration

  • E.F. Adolph et al.

    Multiple factors in thirst

    Am J Physiol

    (1954)
  • T.H. Allen et al.

    Prediction of blood volume and adiposity in man from bodyweight and cube of height

    Metab Clin Exp

    (1956)
  • E.M. Blass et al.

    Drinking termination: interactions among hydrational, orogastric, and behavioral controls in rats

    Psychol Rev

    (1976)
  • E.G. Boring
  • D. Boulze et al.

    Water intake, pleasure and water temperature in humans

    Physiol Behav

    (1983)
  • D.V. Cicchetti

    Extension of multiple-range tests to interaction tables in the analyses of variance: a rapid approximate solution

    Psychol Bull

    (1972)
  • E.P. Cox

    The optimum number of response alternatives for a scale: a review

    J Market Res

    (1980)
  • D.B. Dill et al.

    Calculation of percentage change in volumes of blood, plasma, and red cells in dehydration

    J Appl Physiol

    (1974)
  • A.N. Epstein

    The physiology of thirst

  • J.T. Fitzsimons

    Some historical perspectives in the physiology of thirst

  • J.T. Fitzsimons

    The physiology of thirst and sodium appetite

    Monogr Physiol Soc

    (1979)
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    This paper reports research undertaken at the U.S. Army Natick Research, Development and Engineering Center and has been assigned No. TP2367 in the series of papers approved for publication.

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