Does drinking water help kids concentrate?

By Bob Fear

Does drinking water help kids concentrate?

Drinking enough water could improve your kids’ mental performance. So how much water should children drink a day?

It’s been suggested that children who are mildly dehydrated at school have a low concentration span, impaired fine motor skills and poorer short-term memory. Various bits of research have been done to find out if children who are properly hydrated perform better and are better behaved in school.

Tests have shown that:

  • children who had extra water performed visual attention tasks better than those who hadn’t had any extra water*
  • children who were given water to drink at school had significantly improved skills such as handwriting and ability to copy text**
  • the number of items that children could repeat in sequence was significantly reduced if they became dehydrated ***
  • drinking extra water over the course of the school day helped to improve children’s short-term memory ***

60% of a child’s body is made up of water and just a 1% to 2% loss of water means they’re dehydrated. The UK government’s Eatwell Guide says we should all be drinking around six to eight glasses of fluid a day to stay healthily hydrated, and that children should be gradually working their way up to this amount as they grow. Water, low-fat milk and sugar-free drinks all count towards our daily fluid intake.

Why children need to drink milk

While pure water is always best, milk is particularly important for kids’ health. Children up to the age of two should drink whole fat milk for the calories they need. But babies should not drink cow’s milk until they’re a year old as they need more nutrients. Kids from the age of two can gradually move to semi-skimmed milk as long as they have a healthily varied and balanced diet.

Why we need to limit juices and smoothies

Children and adults alike should drink no more than one small glass of fruit juice, vegetable juice or smoothie a day. When fruit and veg are blended or juiced, they release ‘free sugars’ which can damage your teeth. The natural sugar is less harmful to your teeth when eaten as part of whole fruit and veg. This also means that your daily glass of juice or smoothie is best drunk with a meal.

Stay clear of fizzy drinks

Children should not drink shop-bought fizzy drinks; flavoured water and milk; and squashes and juice drinks with added sugar. All of these are low in nutrients and high in sugar. Children whose drinks contain large amounts of sugar are at risk of tooth decay and becoming overweight.

What are the best drinks for children?

Drinking water and low-fat milk is the best way for children to stay healthily hydrated. Try adding slices of fruit to water to add flavour. Drinking chilled water helps it feel more refreshing. The added buzz of being able to safely dispense filtered and chilled water themselves from a countertop purifier also can encourage kids to drink more water.


*Edmonds CJ & Burford D (2009) Should children drink more water?: The effects of drinking water on cognition in children. Appetite 52(3), 776-9.

**Booth P et al. (2012) Water supplementation improves visual attention and fine motor skills in schoolchildren. Education and Health 30(3), 75-79.

***Fadda R et al. (2012) Effects of drinking supplementary water at school on cognitive performance in children. Appetite 59(3), 730-7.


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