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Woman drinking water on yoga mat

In Queensland, we often talk about dehydration in relation to the elderly, children and babies, or during extreme heatwaves. But the reality is dehydration can affect any Queenslander at any time of year.

Queensland is known for its warm weather, with sunny summers and mild winters delighting locals and attracting many visitors. With a variety of natural spaces to explore, from beaches to the bush and outback, Queensland is a great place to get outdoors and get active. Understanding what dehydration is, how to know if you are dehydrated and how to treat and prevent dehydration will help you enjoy Queensland safely.

What is dehydration?

Dehydration happens when the body loses too much water. Your body loses water by sweating, going to the toilet and by breathing out tiny water particles when you exhale. Vomiting and diarrhoea can also see the body lose larger amounts of water.

Normally, you’re easily able to replace this water by drinking more and by ingesting it in food. Dehydration happens when water is not replaced quickly enough to make up for water that is lost.

How can dehydration happen?

It can be surprisingly easy to become dehydrated.

If you don’t rehydrate regularly, you could become dehydrated if you:

  • do exercise that is strenuous, prolonged or makes you very sweaty
  • do manual work or work in a hot environment
  • spend time in a hot or poorly ventilated indoor environment, like a heated gym, roof space or hot warehouse
  • spend time in a dry environment, like a long-haul plane flight
  • or spend time without access to water.

Dehydration can also occur in windy environments, which allow sweat to evaporate more quickly.

Of course, doing any of these activities on a hot day will see you getting even hotter and sweatier. But it’s also important to pay attention to rehydration during cooler months, when you might not feel like drinking enough water and heated air can dry your skin.

You can also become dehydrated from drinking alcohol or drinks that have caffeine in them, both of which act as a diuretic. This means that they make you go to the toilet more often, losing more water than normal.


Woman drinking water from glass

How do I know if I am dehydrated?

If you are mildly dehydrated, you might experience one or more of these symptoms:

  • thirstiness
  • a dry mouth, lips and tongue
  • headache
  • have urine that is a darker yellow than usual, and less of it
  • light-headedness or dizziness.

If you are severely dehydrated, you might experience one or more of these symptoms:

  • extreme thirstiness
  • have a very dry mouth, lips and tongue
  • crankiness
  • drowsiness
  • feel like you are breathing very quickly
  • have a fast heart rate
  • fainting
  • have very little or no urine.

If you weigh more than one kilogram less after exercising or working, you are likely to be dehydrated.

What happens if I don’t treat dehydration?

Not treating dehydration can have serious, even deadly, consequences. Your body is made up of approximately 50 – 75 per cent water and not having enough of it affects a large number of bodily functions. Dehydration can lead to other heat related illnesses like heat exhaustion and heat stroke, which can occur rapidly and can be fatal.

How to treat mild dehydration

For mild dehydration, the best thing you can do is drink water to rehydrate. Drink small amounts of water regularly. You can purchase oral rehydration solutions at the pharmacy which will also help replace electrolytes. Avoid drinking alcohol or caffeinated drinks.

Glass of water being filled from tap

How to treat severe dehydration

If you, or someone you are caring for, is severely dehydrated, you need to seek medical treatment immediately. Call 000 if you, or a person you are caring for, is feeling very unwell or displaying signs of heat stroke.

How to prevent dehydration

You can follow these steps every day to help prevent dehydration:

  • drink plain water often
  • always carry water with you when you leave the house – use a BPA-free or stainless steel water bottle
  • seek cool or shady places when you are out of the house
  • be mindful of dehydration when doing outdoor activities
  • take extra care on really hot days.

How much water should you drink?

Try to drink enough water every day, even if it isn’t hot or you aren’t doing a lot of exercise. Men should drink 2.6 litres or ten cups of fluid each day. Women should drink 2.1 litres or 8 cups of fluid each day. If you are exercising, sweating a lot or are in a hot environment, you will need to drink extra water to make up for the water you are losing.

If you have questions about how much fluid you should drink, or if you have any medical conditions or are taking any medications that might change your fluid requirements, talk to your doctor about how much fluid you need.

Sports drinks that contain electrolytes are not necessary for rehydration under usual circumstances. These drinks can be used to rehydrate if you have exercised continuously for 90 minutes or more. If in doubt, drink water instead.

As you start a new water drinking habit, you might also want to reconsider your regular drinking habits and rethink sugary drinks. Adding fruit, veggies and herbs to your water can be a good way to boost the flavour in a healthy way, here are a few ideas to help you make water more colourful.

Man drinking water from a glass

Can I drink too much water?

Excessive water intake can cause a rare condition called hyponatraemia. Hyponatraemia happens when very large quantities of plain water are drunk and affects the level of salt in the blood.

If you are dehydrated, drink small amounts of water regularly to give your body time to process it, rather than drinking a lot of fluid in a short space of time.