Challenges in the assessment of total fluid intake in children and adolescents: a discussion paper

Abstract

PurposeIn recent years, evidence has emerged about the importance of healthy fluid intake in children for physical and mental performance and health, and in the prevention of obesity. Accurate data on water intake are needed to inform researchers and policymakers and for setting dietary reference values. However, to date, there are few published data on fluid or water intakes in children. This is due partly to the fact that drinking water is not always reported in dietary surveys. The aim of this paper is to review the current status of the literature and highlight the challenges of assessing total fluid intake in children and adolescents.ResultsFrom the dietary assessment literature it is apparent that children present unique challenges to assessing intake due to ongoing cognitive capacity development, limited literacy skills, difficulties in estimating portion sizes and multiple caregivers during any 1 day making it difficult to track intakes. As such, many issues should be considered when assessing total fluid intakes in children or adolescents. Various methods to assess fluid intakes exist, each with its own strengths and weaknesses; the ultimate choice of method depends on the research question and resources available. Based on the literature review, it is apparent that if the research focus is to assess only fluid intake, a fluid-specific method, such as a diary or record, appears to be a feasible approach to provide an accurate estimate of intakes.

Hydration in Children: What Do We Know and Why Does it Matter?

“…However, assessing fluid intake in children involves multiple challenges (e.g., multiplicity of caregivers and/or locations throughout the day, bias in parental diet records, on-going cognitive capacity development, limited literacy skills, difficulties in estimating portion sizes, differences in child portion sizes compared with those of adults, and a tendency not to finish servings) [21]. Additionally, plain water intake is often overlooked in clinical and observational studies focusing on obesity because water contains no calories.…”

Interventions to increase the consumption of water among children: A systematic review and meta‐analysis

“…On average, among the seven bias domains, 46% domains were classified as “low or moderate bias,” 33% as “serious bias,” 1% as “critical bias,” and 20% as “unclear bias or not applicable.” A large source of risk of bias was measurement of outcome for both RCTs and other designs, due to reliance on 1‐day 24‐hour recall or FFQ; 18/24 RCTs used this and 20/23 of studies with other designs. Retrospective recall for self‐reported or proxy‐reported fluid intake is considered to be unreliable, and repeated recalls and diaries are the most appropriate report‐based methods to assess fluid intake in children and adolescents . Risk of bias due to incomplete outcome/missing data was high in only 6/24 RCTs and unclear in 3/24 RCTs, but for studies with other designs, this was unclear in 5/23 studies, serious in 8/23 studies, and critical in 1/23 studies.…”

Describing water intake in six countries: results of Liq.In7 surveys, 2015–2018

“…If sustained over the longer term, chronic poor hydration is associated with increased risk of chronic disease incidence, progression and/or complications, and mortality [8]. Dehydration significantly magnifies the risk of dying within a year for older adults hospitalized for respiratory illness, gastroenteritis, other gastrointestinal conditions, urinary system infections, cancer, sepsis, cardiac diagnoses, frailty, diabetes and other metabolic disorders [9]. …”