Validation of beverage intake methods vs. hydration biomarker; A short review

Abstract

Introduction: Fluid intake is difficult to monitor. Biomarkers of beverage intake are able to assess dietary intake/hydration status without the bias of self-reported dietary intake errors and also the intra-individual variability. Various markers have been proposed to assess hydration, however, to date; there is a lack of universally accepted biomarker that reflects changes of hydration status in response to changes in beverage intake. Aim: We conduct a review to find out the questionnaires of beverage intake available in the scientific literature to assess beverage intake and hydration status and their validation against hydration biomarkers. Methods: A scientific literature search was conducted. Only two articles were selected, in which, two different beverage intake questionnaires designed to capture the usual beverage intake were validated against Urine Specific Gravidity biomarker (Usg). Results: Water balance questionnaire (WBQ) reported no correlations in the first study and the Beverage Intake Questionnaire (BEVQ), a quantitative Food frequency questionnaire (FFQ) in the second study, also found a negative correlation. FFQ appears to measure better beverage intake than WBQ when compared with biomarkers. However, the WBQ seems to be a more complete method to evaluate the hydration balance of a given population. Conclusions: Further research is needed to understand the meaning of the different correlations between intake estimates and biomarkers of hydration in distinct population groups and environments.