Dehydration occurs when the body does not have enough water to function properly.   Children can quickly become dehydrated when playing outside on hot, humid days.   Dehydration can lead to serious heat illness such as heat exhaustion and heat stroke.   The good news is that it’s easily prevented.

Children are at greater risk than adults for dehydration because:

1. They sweat more when they are active.
2. They produce more body heat.
3. They often don’t feel thirsty. By the time they feel that they need a drink, they are already mildly dehydrated.
4. They don’t drink enough without supervision to replace what they have lost through sweating.
5. They forget to drink when they’re running around and having fun.
6. They absorb more heat from the air and take longer to adapt to hot, humid weather.

How do I know if my child is dehydrated?

Below are some of the signs of dehydration:

• Decreased physical activity
• Lack of tears when crying
• Irritability and fussiness
• Thirst
• A small amount of dark yellow urine

What should I do if my child is dehydrated?

• Give the child cool water to drink.
• Move the child to a cool, shady area.
• Have the child continue to drink sips of cool water over 2-3 hours.
• Seek medical help if symptoms do not improve or get worse.
  

Ways to Prevent Dehydration:

• Use proper clothing
  • Choose light-coloured, light-weight, loose-fitting clothes in hot weather.
  • Choose cotton or a breathable material.
  • Have your child wear a hat.

• Use shade
  • If playing outdoors, use shade as much as possible. When not playing or resting children should sit under trees, umbrellas, in a tent, or in the shade of a building.

• Check the weather
  • Keep young children indoors during hot, humid days, and especially during heat alerts.
  • Avoid activities, where possible, between 10 a.m. and 4 p.m. when the sun’s intensity is highest.
  • If you must go out, keep physical activities light.

• Hydrate adequately
  • Have children carry their own water bottle (minimum 500 ml size).
  • Divide the water bottle into thirds with rubber bands or with a magic marker. This helps children know how much to drink before, during, and after physical activity.
  • Children should drink 1/3 of the water bottle one hour before the activity. During the activity, they should take gulps of water every 20 minutes until they finish the next 1/3 of their water bottle. In the first hour after the activity, they should drink the last 1/3 of their water bottle.
  • Have children refill their water bottle and continue to take sips of water over the next 2-3 hours.
  • Children must drink to a schedule and not when they feel thirsty. In children, the feeling of thirst is delayed. Thirst is the first sign of mild dehydration.
  • Children also need to drink before and after swimming. Water in pools or lakes delays the feeling of thirst, but children are still losing fluids.
  • Children need to continue to drink water after hard activity for several hours until they can produce a large amount of light yellow urine.

Best Fluid to Use:

Cool water is the best fluid to use. It leaves the stomach quickly and helps cool the body from the inside out.

• Sports drinks such as Allsport®, Gatorade®, and Powerade® can be given. However, they are only necessary if the child is very active for 45 minutes or more. Sports drinks can help replace the minerals lost in sweat and provide a small amount of sugar for energy.
• Juice and soft drinks are too high in sugar. They also take too long to leave the stomach and can cause stomach cramping, nausea, and vomiting.
• Some soft drinks also contain caffeine. Caffeine increases the risk of dehydration by making the body lose water faster.

Resources:
For more information on:

• Heat Illness, go to: http://www.wechealthunit.org/diseases-conditions/glossary/heat-and-humidity  
• Heat Index and Humidex, go to Environment Canada, http://ontario.hazards.ca/maps/background/ExtremeHeat-e.html
• Fluid guidelines for young athletes, go to www.momsteam.com