The human body can keep functioning for weeks without food, however it can only last a matter of days without any fluid. This is because the body cannot store and use fluids like it can energy sources. It therefore needs to be replenished frequently in order to make up for losses from bodily functions that require fluid, i.e., waste products, the lungs and skin.
No other substance is as widely used in our bodily processes, and make up, as is water. The figure varies but it is known that water contributes to over two thirds of the weight of the human body! All cells and organs need it in order to function.
Keeping hydrated – Why is water so important?
Water has many vitally important functions. Because the body can also function on smaller intakes of water, we may not realise the impact having too little has. Our body will still run because it has ways of adapting to reduced fluid intakes but it will not run at its peak performance.
Increasing water intake can improve skin, energy levels, digestion and many other internal aspects that we cannot see. It is common that people think they are functioning “normally” until they increase their water intake and realise that their digestion, skin and wellbeing have improved greatly.
The many roles that water plays within the body are complex. The image below simply outlines some of these functions.
What to drink?
Obviously water is the best option. It has zero calories and is perfect for what your body needs! It skips the other ingredients like sugar, sweeteners, acids and caffeine that so many other drinks have. These ingredients can also have a counter effect to the hydrating properties of water, i.e., due to the diuretic effect of caffeine and alcohol that increases urine output, or due to osmosis whereby water diffuses out of a cell to dilute the area with a higher solute concentration. The concentrated solute in this instance might be sugar from a soft drink (this concept is demonstrated in the image below).
Water is also a much cheaper option and is easily accessible from a tap! If you don’t like water, many find mineral water to be an enjoyable alternative.
Individuals who need more fluid
- Those on a high protein diet
- Individuals who have a high fibre intake or take fibre supplements
- During illness that results in increased fluid loss e.g., fever, excessive urination
- During vomiting or diarrhoea
- In hotter climates or conditions that increase sweating
- At higher altitudes – often higher altitudes (generally above 2,500m, 8,200ft) lead to increased rate of breathing and urination, this increases our fluid losses. This includes air travellers!
- Pregnant or breastfeeding women
There are a few conditions that require a decrease in fluid intake. These include some cardiac, respiratory, liver disease and end stage kidney disease. For these individuals, it is particularly important that fluid restrictions are met with quality fluid like water as opposed to fluids such as cordial, juice or alcohol.
Tips to increase you water intake
- Suck on ice cubes in hot weather
- Keep a bottle of water in your bag at all times
- Keep water in the fridge if you like it cold
- Eat 2 pieces of fruit per day, particularly watermelon!
- Ask for water when you eat out
- Add fruit to water to make the taste more interesting e.g. squeeze some lemon or lime in it
- Alternate between water and alcoholic beverages when drinking
- Limit other drinks (e.g. juice, coffee, cordial, soft drink) to 1 glass per day and save the rest for water
- Make a conscious effort to drink water
Contact us for results focused nutritional advice
This article was written by our dietitian Belinda Elwin who is a Dietitians Association of Australia member and Accredited Practising Dietitian and Nutritionist.
If you have diet related questions or if you want healthy eating advice, Contact Us Today!