Fewer than one third of primary school children drink enough fluids, which can affect their cognitive function as well as their physical health.
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Examine more articles on children’s nursing.
In this article…
- Why good hydration is particularly important in children
- NICE’s recommendations for how much children should drink
- The role of schools in promoting healthy drinking
Eileen Jacques is information and helpline manager at Education and Resources for Childhood Continence, Bristol.
Jacques E (2012) Promoting healthy drinking habits in children. Nursing Times; 108: 41, 20-21.
Good fluid intake in children is vitally important as they have immature thirst mechanisms, relatively high rates of fluid loss and are physically active. Poor fluid intake may affect children’s cognitive functioning as well as bladder control. Research shows that children drink seven times as much soft drink as water. Schools have a vital role to play in ensuring that children develop healthy drinking patterns.
Keywords: Child health/School nursing/Hydration/Fluid intake
- This article has been double-blind peer reviewed
- Figures and tables can be seen in the attached print-friendly PDF file of the complete article in the ‘Files’ section of this page
5 key points
- Water makes up 65% of a boy’s body weight and 60% of a girl’s
- Children are more at risk of dehydration than adults
- Boys aged 9-18 years should drink more than girls
- Good fluid intake promotes day and night bladder control
- Research indicates that dehydration may adversely affect cognition
Water is essential for life, it is the largest constituent of the human body and makes up 65% of a boy’s body weight and 60% of a girl’s (Agostoni et al, 2010). Adequate fluid intake is necessary to ensure healthy organ function, including the urinary tract, the heart, lungs, muscles, digestive system and the brain (Manz, 2007).
We lose water when we breathe, sweat and urinate; we also lose water through the lungs, skin and faeces (Stillman et al, 2005). How much water is lost depends on age, body size, physical activity, health and environmental conditions.
There is no provision for water storage in the body so all water lost must be replaced. A loss of 1% of body water is normally compensated within 24 hours but, if further losses occur, there will be a reduction in physical and cognitive performance (Agostoni et al, 2010).
Children and hydration
Adequate fluid intake is particularly important for children as they have immature thirst mechanisms, relatively high fluid loss (due to a large surface area to body mass ratio) and high activity levels (Kaushik et al, 2007). With less developed sweating and kidney functions (Kenney and Chiu, 2001), they are more at risk of becoming dehydrated during hot weather or intense physical activity.
Children’s fluid requirements also vary with age, size and sex; girls have a slightly higher percentage of body fat and store less water than boys (Agostoni et al, 2010).
The thirst signal is triggered when a 1-2% loss of body mass has been reached and the kidneys have started to concentrate urine (Kaushik et al, 2007). Thirst is quenched after an appropriate amount of water is ingested and this occurs well before osmolality is corrected, suggesting that thirst is also associated with rational and emotional cognition, and habitual and social notions of presumed need for water (Al-Awqati, 2007).
As drinking behaviour may develop and be anchored in the toddler age group, it is vital to teach children about the importance of good hydration and establish good drinking patterns at an early age (Epstein, 1991).
The body gets fluid from three sources:
- Drinks, plain water or other beverages;
- Solid foods, especially fruit and vegetables. Water intake from food is approximately 19% of total water intake (Food and Nutrition Board, 2004);
- As a by-product of chemical reactions within the body.
Two large studies have estimated that children should drink eight age-appropriate cups of fluid a day (Food and Nutrition Board, 2004; Sichert-Hellert et al, 2001), but although this figure is easy to remember, it does not take into consideration a child’s age, sex and body mass. National Institute for Health and Clinical Excellence (2010a) has produced more precise estimates of daily fluid intake categorised by age and sex (Table 1).
Fluid intake at school
Research has found that only 29% of primary school children drink the minimum desired fluid intake, while others drink significantly less, and that a child’s drinking pattern is influenced by that of their peer group (Kaushik et al, 2007).
Easy access to water at school and encouragement to drink during the day are vital in maintaining a good fluid intake in school children. School is an important setting in which to promote lifelong healthy drinking patterns.
It is thought that children often undergo a “periodic drought”, drinking little during school hours and drinking to compensate when returning home. Although there has been some research specifically on the link between drinking and childhood cognitive function (Edmonds and Jeffes, 2009; Edmonds and Burford, 2009; Benton and Burgess, 2009), more extensive research on adults has shown a reduction in cognitive function during short-term dehydration. If children who drink little during the school day experience reduced cognitive function in the same way as adults, this would “jeopardise the primary educational function of the school day” (Kaushik et al, 2007).
Research into children’s drinking habits show that many children regard plain water as a poor alternative to soft drinks and that children are concerned primarily with taste and image rather than nutritional and health considerations (Petter et al, 1995). Children aged between seven and 10 years drink about seven times as much soft drink as plain water (Gregory et al, 2000).
To encourage children to drink water it needs to be a pleasant experience rather than one to be endured or avoided. ERIC’s Water is Cool campaign has encouraged schools to provide easily accessible fresh water in place of the old-fashioned water fountains and taps found in many schools, which hold little appeal for children.
Healthy bladders and bowels
The association between inadequate fluid intake and bladder and bowel problems in children is well established.
The kidneys play a key role in regulating fluid balance and removing waste from the body as urine, and they function better in the presence of a good fluid supply (Popkin et al, 2010).
Fluid intake influences the composition and volume of the urine and how frequently a child goes to the toilet. Good fluid intake also helps increase bladder capacity, and helps a child recognise the sensation of a full bladder and develop day and night bladder control (NICE, 2010a; Van Laecke et al, 2009).
If there is good fluid intake with frequent micturition there may also be a reduction in susceptibility to urinary tract infections (Beetz, 2003).
There is very little research that supports the notion that a constipated child will find relief from constipation through drinking more. However, the guideline development group for the recent NICE guidelines for childhood idiopathic constipation determined that an increase in fluid intake is essential in children experiencing constipation (NICE, 2010b).
Education about proper hydration is essential to ensure that children’s drinking patterns are established early. Ensuring a good fluid intake from an early age will have a positive effect upon children’s bladder and bowel control and bladder capacity as well as positive effects upon cognition.
Schools have a important role to play in ensuring that good hydration continues throughout childhood with the provision of easily accessible, good-quality water.
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