Role of Water in the Human Body

Our body is made up of approximately 60% water. Our brain is ~85% water, blood is ~80% water and approximately 70% of lean muscle mass is water. Water plays an important role in all of these major systems and without water, they don't function efficiently. Even a mere 2% reduction in body water can decrease performance, affect short-term memory, focus and increase fatigue. 

Some of the most important roles of water in the body include:

Maintaining blood volume, nutrient transportation and waste removal

Water is the main component of blood and essential for transportation of nutrients and removal of waste in the body. Blood delivers nutrients such as glucose, sodium, potassium and amino acids to our tissues for cell life and function. Blood also carries toxins and waste products away from our cells to our kidneys and liver for filtration and removal. The kidneys regulate how much water we excrete or conserve to maintain blood volume and concentration.  

Chemical and metabolic reactions

Water participates in hundreds of important metabolic reactions that occur in the body known as ‘hydrolysis reactions’. These reactions break down the carbohydrates, fats and proteins in our food so that our body can use them for energy and create the building blocks of life.

Protects tissues and joints

Water helps keep sensitive tissues such as your eyes, nose, mouth and brain moist. It also functions like a lubricant and cushions joints like your spine and knee so they can easily move against each other.

Temperature regulation

Water has a large heat capacity which helps control body temperature and allows us to adapt to changes in environmental temperatures. If the environmental temperature increases above body temperature, the body begins to sweat. Sweat evaporates off the skin surface which releases heat and cools the body down efficiently.

Stay hydrated

Consuming water regularly throughout the day is important to prevent dehydration. We lose water through sweat and breathing (insensible losses) and of course, urine. The insensible losses account for ~50% of the total water turnover.

The average adult requires roughly 2-3L of water per day to maintain water balance and keep the body systems functioning efficiently. This will of course vary with different environmental conditions, physical activity and your individual metabolism. 

For ideas on how to drink more water, check out our 7 tips.

7 Tips to Drink More Water

For some, drinking enough water each day is easier said than done. Maybe you dislike the taste, get too busy or just plain forget about drinking until bedtime, when chugging eight glasses is highly impractical (and not advised!). To help you drink more water, we’ve put together 7 tips you can use to develop this healthy and essential habit.

  1. Buy a water bottle (and use it)


    Invest in a high-quality, stainless steel or heavy duty BPA free plastic water bottle and take it with you everywhere! If you regularly forget to drink water, find ways to keep your water bottle visible. Keep it on your bedside table, on your desk and in the car. Increase your availability of water and opportunity to drink and chances are you will.

  2. Add sugar-free flavour


    If plain water isn’t your thing, try flavouring it with fresh fruits and herbs. Try these tasty combinations:

    Cucumber and mint
    Fresh lemon or lime wedges – squeeze some of the juice into your water first
    Frozen berries – strawberries, raspberries, blueberries. These also double as ice cubes and are great for summer
    Fresh lemon and ginger root
    range slices & blueberries
    Watermelon and mint
    Rosemary and grapefruit
    Kiwi and cucumber

  3. Switch things up and go for a sparkling mineral water

    Soda streams are all the rage at the moment and are a cheap way of making your own bubbly water without the wastefulness of buying numerous bottles from the supermarket.

  4. Add water to your daily routine

    Adding water into your morning and night time routine is an easy way to ensure you drink at least two glasses of water each day. Get into the habit of drinking a glass of water before you have breakfast and another right before you brush your teeth at night.

  5. Turn your water bottle into a timer


    You can create drinking goals and mark them on your water bottle to hit targets by certain times of the day. Use tape or a permanent marker to mark how much water you aim to drink by a particular time. This is a helpful way to keep track of whether you are going to hit your goal water intake (or not). You can also buy motivational water bottles pre-marked or even fancier products with inbuilt computers that track your water consumption.

  6. Create mental triggers


    Identify some mental prompts to drink water. For example, if you feel hungry opt for a glass of water before eating. Not only will this keep you hydrated it will could also possibly curb your hunger.

  7. Be active


    We lose water in sweat which needs to be replaced during and after exercise. If you're struggling to drink, go for a brisk walk or do some exercise in the gym. This will help drive thirst as your body works to restore its hydration balance or homeostasis.

Happy drinking!