The Early Signs, Symptoms and Effects Of Dehydration On Children

The human body consists of over 70% water, with even higher amounts in newborns. It is crucial for a variety of bodily functions including just to name a few; food digestion, waste and toxin removal, energy and cell regeneration, transporting of oxygen throughout the body and powering our immune systems.

Dehydration is simply defined as the excessive loss of body fluids, which will mean the body will find it harder to perform the functions necessary for an optimal healthy lifestyle. In children, this can often be due to extended periods of vomiting and diarrhea, but also from being exposed to an environment with extreme heat and/or humidity.

As children experience some rapid stages of growth and development, their bodies are processing an extraordinary amount of water relative to their consumption, placing a significant importance on the amount they consume. Naturally, daily intake varies depend on variables such as age, weight, common activities, and environmental factors, but parents and supervisors must be vigilant to monitor for the early signs and symptoms of dehydration in children to avoid the development of harmful effects.

How to Identify the Early Signs and Symptoms of Dehydration

Scientists, doctors and natural health professionals know that dehydration can be linked as the cause of many major behavioral conditions and illnesses.  Poor nutrition & dehydration has shown to have serious effects impacting a child's school performance by:

  • Increasing fatigue
  • Reducing memory
  • Making concentration difficult
  • Trouble with basic maths
  • Increasing behaviours that mimic ADD/ADHD

The biggest trigger of daytime fatigue is lack of water.  

A mere 2% drop in body water can trigger a range of early signs and symptoms of dehydration in children. Be sure to monitor for:

  • General feelings of thirst (feeling thirsty is actually one of the early signs the body is already dehydrated)
  • fuzzy short-term memory loss
  • trouble with basic maths
  • difficulty focusing
  • dry mouths, lips and eyes
  • fatigue and yawning
  • erratic and moody behaviour
  • constipation
  • aches and pains unrelated to an injury or infection
  • craving sugar, sweets and caffeine

The adolescent brain functions much better if at least 1 to 1.5 litres of quality water is consumed during the average 6.5 hours the student is in school. 

How to Prevent or Reduce the Negative Effects of Dehydration In Your Children

Increasing the intake of water is very important but to best assist cellular hydration outcomes you also should consider the quality of the water intake.  When experiencing dehydration symptoms it is essential to also choose clean filtered water with the added benefit of naturally alkaline/electrolyte minerals that will assist in the absorption of water into the cells.

If your child is under twelve months old, consulting a doctor is always advised.

Infants being breastfed may be advised to have an increased feeding schedule whereas bottle-fed children may be advised to include an oral rehydration solution for the initial 12 hours after dehydration effects initially present.

For older children (those above 10kg), they should consume 250ml of fluids every hour for four hours after early signs of dehydration symptoms are identified. Again, illness might make this difficult, so smaller sips of increased frequency is potentially necessary.

When children are given milk, fruit juice and softdrinks to the exclusion of water, it only compounds the dehydration problem. In addition to this, a cultivated preference for the taste of these drinks will automatically reduce a child’s free urge to drink water, which of course contains no sugar!  This effect will compound later on in adult life where eventually the signals of thirst get turned off and the dehydration state continues unabated.  Studies show that up to 92% of Australians are dehydrated.

We must address the need for healthy choices at an early age… Let’s encourage the next generation to become the ‘wellness’ generation!


Roland J, Fisher JK , MD, What Is the Average (and Ideal) Percentage of Water in Your Body? Healthline (2019)

Gavin ML, MD, Why Drinking Water Is the Way to Go, Kids Health (2018)

Faizan U, Rouster AS. Nutrition and Hydration Requirements In Children and Adults. [Updated 2020 Sep 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from:

Vega RM, Avva U. Pediatric Dehydration. [Updated 2021 Aug 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from:

Benson, D, Thirsty? You’re already dehydrated, Baylor College of Medicine (2021)

NHS, Dehydration (2019), 

The Royal Children’s Hospital Community Information and Anaesthesia and Pain Management departments, Dehydration, (2018)

Want to learn more?

Chat with one of our Hydration Experts now!

Free Shipping

Free Shipping

90 Day Money-Back Guarantee

90 Day Money-Back Guarantee

5 Year Warranty

5 Year Warranty

Complimentary Reminder Service

Complimentary Reminder Service