How much water should you actually drink each day?

Water is the elixir of life and without it we can’t survive. But when it comes to how much we should be drinking, there is a plenty of wishy-washy information out there.

Firstly, why is water so important?

Even being a little bit dehydrated can take its toll on the body, according to Nutrition Australia senior nutritionist Aloysa Hourigan.

“Hydration is critical because a very large percentage of our body is made up of water and we need to be replenishing it,” she says.

“We lose it naturally even just by breathing, every time we go to the toilet, evaporation through sweat – it’s a thing that needs constant replacing and if it’s not there in adequate amounts we can become unwell.”

The nasty side effects of dehydration include headaches, dizziness, hunger, extreme thirst and tiredness.

There is also research suggesting dehydration can contribute to urinary tract infections.

How much water should you drink?

There is a well-known mantra that we need to drink eight glasses a day, but this doesn’t factor in gender, size, exercise habits, or medical conditions.

According to the Australian Government nutritional reference guide:

  • The average-sized man will need to drink more fluid than the average women, with a recommended 2.6 litres (10 cups) per day.
  • Females should be having 2.1 litres (eight cups) of fluid a day, but this will increase when pregnant and breastfeeding.

There is also research to suggest that women’s fluid levels may fluctuate during their hormonal cycle, but just how much and when is still not known.

How to tell if you’re drinking enough water

In reality everyone is different, and your body is good at telling that you need water, says Kidney Health Australia clinical director Shilpa Jesudason.

Shilpa recommends “drinking for thirst” and sticking to water rather than sugary beverages.

Alternatively, keeping an eye on your urine can be a useful gauge.

“Your urine is supposed to be a pale-yellow colour, so if it’s dark yellow, you probably need more fluid,” Shilpa says.

Water and your kidneys

Fortunately if you do become dehydrated, the body has a system that kicks in – your kidneys.

Shilpa says these powerful little organs are highly “sophisticated” and regulate the amount of H2O in your body.

The two bean-shaped organs process about half a cup of blood every minute, removing toxins as well as excess water, and sending them to your bladder.

“Your kidneys work out how much you need, so if you drink a lot of water the chances are you are going to pee out most of it and the body will keep exactly what you want,” Shilpa says.

“But if you are dehydrated and not drinking enough water your kidneys will kick in, preserving water.”

“But if you’re not getting enough water or losing a lot of water over a longer period of time your kidneys will not be able to compensate.

“You will get to a point where you blood pressure may start to go down and you don’t get enough blood supply to vital organs and things start to shut down.”

World Kidney Day is in March each year. Get a read on your kidney health with the Kidney Australia Kidney Risk Test.