Nutrición Hospitalaria
ISSN 1699-5198 ISSN 0212-1611
YOUNG, Hayley A. BENTON, David. The use of moderated mediated analysis to study the influence of hypo-hydration on working memory. []. , 33, 3, pp.71-75. ISSN 1699-5198. https://dx.doi.org/10.20960/nh.320.
^len^aIntroduction: To date, dehydration has been typically reported to influence psychological parameters when there has been at least a 2% loss of body mass, although there has been little examination of those going about their everyday lives, those who have lost less than 1% of body mass. In such situations factors such as the initial hydration status and individual differences in the response to a reduced fluid intake are likely to be influential. Yet to study the complexity added by such additional variables novel methods of statistical analysis are required. Objectives: The present study describes the use of moderated mediation, an approach that asks various questions: firstly, is drinking influential?; secondly, does a mediator (e.g., thirst) sit between an independent and dependent variable?; and thirdly, does an effect only occur under certain conditions such as initial osmolality?. Method: In the study, 118 subjects were exposed to 30 oC for four hours during which they half drank 300 ml water. The serial sevens test of working memory was performed before and at the end of the procedure. Results: A 0.6% loss of body mass reduced the efficiency of working memory. Those who consumed water had better working memory; working memory was worse in participants who lost more body mass or became thirstier, but only in those with higher levels of baseline osmolality. Conclusions: Small variations in hydration status influenced cognitive functioning although there were individual differences in the response. The parameters that influence an adverse response to hypo-hydration need to be established to allow giving appropriate advice.
: .