How Much Water Should I Drink?
Staying hydrated for good health
You’ll have no doubt heard about “eight glasses a day” – but everyone is different, and our bodies’ requirements are flexible and varied. In fact, the amount of fluid you need depends on:
Your body size
Your metabolism
Daily activity
How hot it is or how humid it is
Your diet
Your life stage
Any health conditions you may have
In short, most adults should ideally have around 2 to 3 litres of fluid a day. So, how do you make it easier to build hydration habits that keep you feeling energised, clear‑headed and comfortable throughout the day?
How Much Water Should I Drink a Day?
Hydration isn’t one‑size‑fits‑all. Your needs change from day to day, with a number of factors influencing how much fluid your body uses.
Body size and metabolism. Your body requires water for most functions – this means people with larger bodies or higher energy needs will more than likely need more. Your body also loses water via simple functions such as breathing, sweating and digestion.
Activity level. Even light exercise increases fluid loss, so if you consider yourself an active individual, you’ll be losing even more water through sweat. It makes sense to drink before, during and after your movement, to help you stay comfortable and maintain performance.
Climate and temperature. No need to mention that our hot and often humid Australian weather will have an effect on the amount you sweat. Naturally, this means your body needs more fluid to stay balanced. If you work outdoors, you need to drink more than the general guideline.
Diet. What you eat on a daily basis also contributes to your daily fluid intake. If you eat a lot of fruit or vegetables, the water these foods contain will help with your hydration levels. If you like salty or high‑protein foods, these are likely to increase your fluid needs. And yes, alcohol can also affect hydration by increasing fluid loss.
Pregnancy. If you’re pregnant or breastfeeding, unsurprisingly your daily fluid needs increase. The National Health and Medical Research Council (NHMRC) recommends higher intakes during these stages to support both parent and baby.
Health conditions. Illness, fever, vomiting and diarrhoea can increase fluid loss. Some medications also affect hydration. If you have a health condition that influences fluid balance, it’s worth speaking to your doctor about your fluid needs.
Easy Ways to Tell You Are Drinking Enough
Your body is clever - it gives you clues about your hydration status. Pay attention to these simple signs:
Your urine is pale or light yellow
You feel alert and comfortable
You are not excessively thirsty
You are going to the toilet regularly
These everyday cues are often more helpful than aiming for a fixed number of glasses.
Why Does Water Matter So Much?
Water helps:
Regulate body temperature
Transport nutrients and oxygen
Remove waste products
Lubricate joints
Support digestion
Maintain concentration and energy levels
Signs You’re Not Drinking Enough Water
Even mild dehydration can affect how you feel. You might notice that you are not thinking clearly, or that you feel a little sluggish.
Dehydration can sneak up on you, especially when you are busy or distracted. Look out for these common signs:
Feeling thirstier than usual
Dark yellow urine
Your mouth feels dry
Dizziness
You’re a bit more tired than normal or low energy
Headaches start creeping in
Difficulty concentrating
Constipation
Fatigue and reduced concentration
Poor physical performance
Mood changes and irritability
Not drinking enough water can also increase the risk of kidney stones in some people
Severe dehydration can become a medical emergency, especially for young children and older adults. If someone shows signs of confusion, rapid heartbeat, extreme thirst or very little urine, seek medical help promptly.
Does It Matter What Type of Water You Drink?
Most people can stay hydrated with a variety of drinks. Here is a simple guide to common options.
Tap water. Australian tap water is generally safe, clean and affordable. It is one of the easiest ways to stay hydrated.
Filtered water. Some people prefer the taste of filtered water. Filtration can remove certain particles, but it does not usually make water healthier for most people.
Sparkling water. Sparkling water hydrates just as well as still water. Choose varieties without added sugar if you want a low‑kilojoule option.
Mineral water. Mineral water contains naturally occurring minerals. It can be a refreshing alternative, although it is not necessary for hydration.
Flavoured water. Check the label - some flavoured waters contain added sugar or sweeteners. These can still contribute to hydration, but it is helpful to be aware of what you are drinking.
Tea and coffee. Tea and coffee count towards your daily fluid intake. Despite common myths, moderate amounts do not dehydrate most people. Just keep an eye on sugar and other additives if you are having them often.
Simple Tips to Help You Drink Enough Water
Small habits can make a big difference. Try:
Start the day with a glass of water.
Carry a reusable water bottle.
Drink with meals and snacks.
Add lemon, berries or mint for flavour.
Drink water before you’re thirsty
Eat water‑rich foods like watermelon, oranges and cucumber.
Keep water visible at your desk.
Set reminders if you often forget.
Drink extra fluids during hot weather and exercise.
Can You Drink Too Much Water?
It’s uncommon, but it can happen.
Drinking extremely large amounts of water in a short time can cause something called hyponatraemia - diluted sodium levels in the blood. It’s rare in everyday life, but it has known to be serious – and occasionally fatal - in specific situations, especially with extreme endurance exercise or underlying health conditions.
If you have kidney, heart, or liver conditions, or take medications that affect fluid balance, it’s worth getting personalised advice from a health professional.
When Should You See a Doctor?
If you experience ongoing dizziness, headaches, extreme fatigue or signs of dehydration, it is worth speaking with a GP.
Westfund members can access Doctors on Demand, which makes it easier to get medical advice from home.
Westfund also offers a range of Health and Wellbeing programs* that support members in staying healthy, not just when they are unwell.
Drinking enough water isn’t a specific formula. Instead of chasing a perfect number, pay attention to your body’s signals and build small habits that help you stay hydrated every day.
FAQs
How much water must I drink if I exercise?
You’ll need to add extra fluid to your day to replace the water lost through sweat, ideally sipping water before, during, and after your workout.
Is sparkling water as hydrating as still water?
Yes, plain sparkling water is just as effective at hydrating your body as regular tap water
What colour should urine be if I am hydrated?
Your urine should ideally be a pale, clear, straw-like yellow colour if you are properly hydrated.
The information provided is general in nature and does not replace professional medical advice.
*Annual limits, waiting periods and eligibility criteria apply. Benefits and programs are subject to your level of cover. Please refer to your Policy Summary or check your Extras limits via Members Online or the Westfund app for full details.
Sources
Australian Government, National Health and Medical Research Council (NHMRC)
Australian Drinking Water Guidelines (ADWG)
Australian Institute of Health and Welfare (AIHW).