NHD Paediatric Hub
Children and hydration: What should we know
As the summer months are upon us, even if the weather is not as expected, there is more discussion about hydration. However, it is not just a summer subject and it can be a complex one to change the habits of children as well as adults. This article unpacks the need for hydration and considers the recommendations and the dangers of dehydration. Aliya's useful infographic has been included, which can be used with families.
Water makes up a significant proportion of the body, so ensuring adequate hydration is essential for all of us, as water maintains normal bodily functions. However, it is not always straightforward to achieve.
HOW MUCH OF OUR BODIES IS WATER?
Whilst this varies from person to person, a recent study looked at the amount of water in different aged children and also compared ‘normal’ and ‘overweight’ subjects. They found that total body water (TBW) was similar in boys and girls aged 3-10 years of age (62%). In males, this remained the same until age 61 plus, when it decreased to 57% in ‘normal’ weight males and was significantly lower in ‘overweight’ males. In females, the TBW decreased to 55% in the 11-20 year-old group and then remained stable until age 61 plus, when it decreased to 50% in ‘normal’ weight individuals. The ‘overweight’ females also had significantly lower TBW than the ‘normal weight’ females.(1) EFSA Journal data(2) found ages 3-10 varied between 64.8 and 66.0% in boys and 6.2 and 64.3% in girls, with percentages going up and down in those age ranges but did not compare ‘normal’ with ‘overweight’. This gives further evidence of the large proportion of the body which is made up of water.
Why is good hydration important?
The human body loses water largely through urine, faeces, sweat and tears. It needs to replace this fluid in order to maintain equilibrium and the percentage water discussed above. Without good hydration, the body does not function properly.
SYMPTOMS OF DEHYDRATION
When discussing the symptoms of dehydration, it is important to note that good hydration is not just the absence of dehydration. Good hydration is positive beyond prevention of the NHS symptoms found in Table 1.(3) Good hydration supports health in a wide range of ways, too many to discuss the research in depth in this article.
Symptoms of dehydration in adults and children include:
- Feeling thirsty
- Dark yellow, strong-smelling pee
- Peeing less often than usual
- Feeling dizzy or lightheaded
- Feeling tired
- A dry mouth, lips and tongue
- Sunken eyes
Signs of dehydration in a baby may include:
- A sunken soft spot (fontanelle) on top of their head
- Not having many wet nappies
- Being drowsy or irritable
- Few or no tears when they cry
- Sunken eyes
HOW MUCH WATER IS RECOMMENDED?
Recommendations vary within the UK. Table 2 below shows different recommendations given to children from organisations within the UK, as well as the EFSA adequate intakes. Notice the American guidance quoted in the NICE constipation guidlines outlining both total water intake from food and drinks, as well as the recommendations from drinks separately.
Also note the sometimes-significant difference in recommendations for children at different ages between the bodies. All three organisations recognise that requirements will vary including with exercise and climate. When advising families on adequate hydration this variation of requirements must be considered and discussed with them.
DANGERS OF DEHYDRATION
Dehydration can be fatal but before that, it can lead to a reduction in cognitive function, thermoregulation, immunity, gastrointestinal health (through constipation), kidney function, heart health, an increase in urinary tract infections and
more.(4) It is clear it is essential to keep hydrated.
American recommendations quoted in NICE guidance CG99
- | American recommendations quoted in NICE guidance CG99 | American recommendations quoted in NICE guidance CG99 | British Dietetic Association recommendations (5) | EFSA recommendations for Adequate intake (6) |
|---|---|---|---|---|
- | Total water intake per day, including water contained in food | Water obtained from drinks (ml/day) | Adequate water intake from drinks (ml/day) | Total water intake per day, inc water contained in food |
Infants 0 to 6 months | 700ml assumed to be from breast milk | - | - | - |
7 to 12 months | 800ml from milk and complementary foods and beverages | 600ml | 640-800ml | 800-1000ml |
1 to 3 years | 1300ml | 900ml | 1-2 years = 880-960ml 2-3 years = 1040ml | 1-2 years = 1100-1200ml 2-3 years = 1300ml |
4 to 8 years | 1700ml | 1200ml | 1280ml | 1600ml |
Boys 9 to 13 years | 2400ml | 1800ml | 1680ml | 2100ml |
Girls 9 to 13 years | 2100ml | 1600ml | 1520ml | 1900ml |
Boys 14 to 18 years (as adults) | 3300ml | 2600ml | 2000ml | 2500ml |
Girls 14 to 18 years (as non-pregnant or lactating adults) | 2300ml | 1800ml | 1600ml | 2000ml |
WHAT SORT OF FLUID IS RECOMMENDED?
Sugar-sweetened beverages are not recommended for children. The NDNS data shows that in the 11 years since 2008 intakes in children have been reducing. However, for 2016 to 2019, children aged 1.5-3 years were still consuming 19g/day and 11-18 year-olds 142g/day. (7) There is a way to go in reducing these beverages.
According to SACN, children aged 1-5 should have mainly milk (whole or semi-skimmed milk) and water (in addition to breast milk). Older children are encouraged to have water, milk (skimmed or semi-skimmed) or fruit juice (the latter limited to 150ml per day). (8) Two campaigns by Food Active seek to support this. Kind to Teeth (9) is a campaign aimed at the early years and Give Up Loving Pop (GULP)(10) is aimed at older children. Food Active has several free resources available to support this work.
HELPING CHILDREN DRINK MORE WATER
The infographic below could be a helpful tool to use with families to support them in increasing their children’s water intake.
A word of caution...
When talking about hydration two other issues must also be considered:
- Culture. Being culturally sensitive to the families to whom the messages are directed is key. For some cultures, consuming sweetened tea from a very young age is normal and a healthcare professional saying it is bad could make the family feel pushed out. Open discussions are
important here. - Safety. Whilst most children will struggle to consume enough water, care should be taken when delivering these messages, so that children don’t have too much. Discussing the amounts and how to spread drinks throughout the day is also essential.
Conclusion
Hydration is essential to health. Children need to be supported to consume more water for their health. Small changes to support this whilst considering culture, current habits and individual hydration needs are essential to support families.
Twitter: @aliyaporter
Facebook: @porter_nutrition
www.weaningcentre.co.uk
www.porternutrition.co.uk
Aliya Porter, RNutr
Freelance Registered Nutritionist
References
Lu H, Ayers E, Patel P, Mattoo TK. Body water percentage from childhood to old age. Kidney Res Clin Pract. 2023 May;42(3):340-348. doi: 10.23876/j.krcp.22.062. Epub 2023 May 16. PMID: 37313612; PMCID: PMC10265208. Accessed 4th Jun 2024 from https://pubmed.ncbi.nlm.nih.gov/37313612/
EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA) (2010) Scientific Opinion on Dietary reference values for water. EFSA Journal 2010; 8(3):1459. [48 pp.]. Page 10 doi:10.2903/j.efsa.2010.1459. Accessed on 2nd July 2024 at https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2010.1459
- NHS (2022) Dehydration. Accessed 2nd July 2024 https://www.nhs.uk/conditions/dehydration/
- Popkin, B. M., D'Anci, K. E., & Rosenberg, I. H. (2010). Water, hydration, and health. Nutrition reviews, 68(8), 439–458. https://doi.org/10.1111/j.1753-4887.2010.00304.x Accessed 2nd July 2024 at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2908954/
British Dietetic Association (2023) Fluid (water and drinks) and hydration. Accessed 4th June 2024 at: https://www.bda.uk.com/resource/fluid-water-drinks.html BDA (2023)
EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA) (2010) Scientific Opinion on Dietary reference values for water. EFSA Journal 2010; 8(3):1459. [48 pp.]. Page 1 doi:10.2903/j.efsa.2010.1459. Accessed on 2nd July 2024 at https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2010.1459
PHE and FSA (2020) National Diet and Nutrition Survey Rolling programme Years 9 to 11 (2016/2017 to 2018/2019). Accessed on 2nd July 2024 at: https://assets.publishing.service.gov.uk/media/5fd23324e90e07662b09d91a/NDNS_UK_Y9-11_report.pdf
Office of Health Improvement and Disparities (2024) Feeding young children aged 1 to 5 years - summary report. Accessed 2nd July 2024 at: https://www.gov.uk/government/publications/sacn-report-feeding-young-children-aged-1-to-5-years/feeding-young-children-aged-1-to-5-years-summary-report#
Food Active (2018) Kind to Teeth. Accessed 2nd July 2024 at: https://foodactive.org.uk/what-we-do/campaigns-and-interventions/kind-to-teeth/
Food Active (2015) Kind to Teeth. Accessed 2nd July 2024 at: https://foodactive.org.uk/what-we-do/campaigns-and-interventions/give-up-loving-pop/