The fastest cure for dehydration isn't sports drinks, soft drinks or even fruit juice.

The fastest cure for dehydration isn't sports drinks, soft drinks or even fruit juice.

... Somebody bring me some water, can't you see I'm burning alive ...

While she was singing about her broken heart at the time, Melissa Etheridge really did have a point. Without adequate amounts of water, we literally would burn alive.

Next to air, water is the most necessary element for human survival. In fact, proper hydration is essential for life. We can live without food for almost two months, but without water for only a few days. Most people have no idea about how much water they should drink throughout the day, and did you realise more than 75 per cent of us live in a constantly dehydrated state?

Why do we need water?

The reality is, without water pulsing through our bodies we would eventually be poisoned by our own waste products. Uric acid and urea is removed via the kidneys and this is dissolved in adequate amounts of water. If there isn't enough water in our system, waste products are not removed as effectively and may build up as kidney stones.

Water is also vital for chemical reactions in digestion and metabolism. It carries nutrients and oxygen to cells through the bloodstream and helps to cool the body through perspiration.

Water lubricates our joints and we even need it to breathe, as our lungs must be moist to take in oxygen and excrete carbon dioxide. Staying hydrated also helps you concentrate.

What are the signs and symptoms of dehydration?

Thirst is not the best indicator of dehydration, as the thirst mechanism only kicks in when you are already mildly dehydrated. While for some people this might not be the most PC type of hydration assessment, the best way to check whether you are drinking enough water is to regularly check the colour of your urine. If it looks like a Berocca that has just dissolved in a glass, you're high on the dehydration scale. Ideally, your urine should be clear or a very light straw colour. A number of mining companies and sporting teams now use urine charts to educate people to monitor their own hydration levels.

Other symptoms of dehydration include headaches and dizziness; decreased energy or fatigue; dry lips, mouth and skin; nausea; constipation; increased body temperature; loss of concentration; and irritability.

How do we become dehydrated?

We continually lose water during the day through sweating, breathing and going to the toilet (through urine).

Each person has different water intake requirements based on their gender, weight, climatic conditions, activity levels, travel requirements, altitude and consumption of diuretics (caffeine in coffee, Coke, energy drinks).

Do other drinks count?

Water is the best choice when it comes to reaching your daily fluid requirement. It contains no calories or sugar, and it's generally free. You can also meet your daily fluid intake with milk, fruit juices or teas. It's important to remember, though, that these are more likely to contain calories – usually from sugar. A freshly squeezed fruit juice contains lots of vitamins and can help make up one of your portions of fruit and vegetables for the day. Commercially manufactured fruit juices can contain lots of sugar and be acidic, both of which are bad for your teeth. Therefore, it's best to limit how much fruit juice you drink and go for the simple high quality H2O.

Drinks that contain caffeine such as tea, coffee and cola can contribute to your fluid intake, however they are also diuretics (increasing the amount of urine you produce) and can cause you to become dehydrated. Drink water alongside alcohol (aim for a water chaser after each standard drink) and always stick within the recommended alcohol limits.

Is two litres a day enough?

Yes, and no. It depends on your weight and activity levels.

We've all heard the advice to drink two litres of water per day, or 8 x 250ml glasses. The problem with this is that it assumes the environment you're in is cool, you weigh 68 kilograms and you're physically active for only about 20 minutes each day.

Recent studies have shown active males and females need to consume 44ml of water per kg of body weight a day to stay hydrated, and 33ml/kg body weight during inactive days. This is a huge difference from the generic "drink two litres a day" advice.

Performing at your peak

Drinking the right amount of water ensures your body functions efficiently, makes you feel healthier and more alert, and reduces the risk of serious health problems. Always have a water bottle in your car or on your desk at work.

1. Have a glass or two of water as soon as you wake up each day.

2. Have a water chaser after a soft drink, coffee, tea or alcohol.

3. Drink water regularly throughout the day. We often mistake hunger for thirst.

4.Drink more water on hot days and when you travel on planes.

5. Always have a water jug in meeting rooms.

What are your tips for staying hydrated throughout the day?

(Source: David Dawson, The Performance Clinic)