The impact of water on your health

Drinking enough water is essential to staying healthy and avoid becoming dehydrated, but many of us still don’t consume enough.

Australia’s dietary guidelines recommend we “drink plenty of water” — but it is difficult to know exactly how much is the right amount.

​So why is water so important and how much should we drink?​

You can’t survive without water, which makes up two-thirds of the human body.

Rachel Murphy of the Victorian Health Promotion Foundation (VicHealth) says water is essential for life and plays an important role in most bodily functions, including digestion and temperature regulation.

The cells and organs of the body need water to function properly and we also need water to keep the kidneys healthy and to flush body waste, to lubricate the joints and to deliver oxygen around the body. It also makes your skin look better and healthier.

During everyday functioning, water is lost by the body and needs to be replaced. We lose water through sweating, urination and even breathing.

“The general recommendation is to drink about eight cups of liquids a day (one cup equals 250ml) for women (nine cups in pregnancy and lactation) and about 10 cups for men,” she says. “It is preferable that most of the liquid we drink is plain water.”

How much you need to drink depends on your activity levels too. If you go running in hot weather, for example, you will need to drink more water.

“You may need to drink more water if you live in a hot climate or participate in physical activity due to increased fluid losses from sweat,” Murphy says.

What happens to your body if you don’t drink enough water?

The symptoms of dehydration include feeling thirsty, dark yellow urine, feeling dizzy and tired, having a dry mouth and urinating less than four times a day. Murphy adds that the symptoms can be subtle, such as feeling unable to concentrate.

You may be more likely to become dehydrated if you have diabetes, a high temperature, if you vomit or have diarrhoea, heatstroke or if you have drunk too much alcohol.

“Your body relies on water to keep it hydrated and performing at its peak,” Murphy says. “When you don’t drink enough, you can feel slow and lethargic, your senses become weak and your physiological responses and reaction times will be impaired.

“When these symptoms go on over a long period of time they can develop into serious health problems and increase your risk of kidney stones, gastrointestinal problems and some cancers,” she adds.

Fluid intake can also affect saliva production which is essential for maintenance of oral health.

If you are dehydrated, your pharmacist may recommend oral rehydration sachets —  powders that you mix with water before drinking.

But if you are seriously dehydrated, you will need to seek urgent medical help. The symptoms of severe dehydration include feeling extremely fatigued and disoriented, having a weak or rapid pulse, or not urinating in eight hours.

How to stay hydrated

Murphy says the best way to make sure you are always hydrated is to drink water regularly throughout the day. A good way to do this is to carry a refillable water bottle with you, so you can sip water when you are out and about.

Instead of reaching for fizzy drinks, try making water more interesting by adding a slice of lemon or a dash of cordial with no added sugar.

Eating fruit and vegetables can also help keep you hydrated —  as well as provide essential nutrients —  as they contain water.

Overall, a good way to gauge whether you are drinking enough water is to check how often you are going to the toilet. You should drink enough during the day so that your urine is pale and clear.