Water is defined as an essential nutrient because it is required in amounts that exceed the body’s ability to produce it. All biochemical reactions occur in water. It fills the spaces in and between cells and helps form structures of large molecules such as protein and glycogen. Water is also required for digestion, absorption, transportation, dissolving nutrients, elimination of waste products and thermoregulation.
Water accounts for 50-80% of body weight, depending on lean body mass. On average, men have a higher lean body mass than women and higher percentage of body mass as water than in women. The relative mass of water decreases in both men and women with age.
So, how much water do I need?
Human requirements for water are related to metabolic needs and are highly variable. They depend on your gender, age, activity levels and the outside climate. Requirements are also different during pregnancy and breastfeeding. However, a good place to start is to aim for is 2-3L/ day.
When we exercise at high intensity or in hot temperatures, our fluid requirements are greater because we lose water from the body through sweating. We need to sweat in order to cool our bodies down so we can continue to perform at our best. Everyone needs extra fluid for each hour of strenuous activity completed.
Warning signs of dehydration
- Dizziness and light headedness
- Muscle cramps
- Nausea / headaches
- Inability to concentrate
- Dark urine / infrequent urination
- Dry mouth and throat, thirst
- Dry skin
Tips to drink more water
- Start your day with a glass of room temperature water and a squeeze of fresh lemon
- Carry a water bottle with you, and place it on your desk at work
- Have a glass of water with all your meals and snacks
- Add some lemon slices, mint leaves or strawberries to a jug of water for a flavour boost
- Drink herbal teas, these can be enjoyed hot or you can cool them down, add some ice and lemon slices, then make into an iced tea
- Eat more fruits and vegetables that have a high water content, such as watermelon, blueberries, raspberries, pineapples, celery, cucumber, iceberg lettuce and tomatoes (NHMRC 2019 / Nutrition Australia 2012).