However, we need it all - losing just one percent of our body weight due to fluid loss can cause dehydration and any more than that can lead to serious medical complications. We are constantly losing water, by sweating or urinating, so by drinking water were keeping our supplies topped up.

How can I tell if I am dehydrated?

The easiest way is to look at the color of your urine. If it is pale, you're probably ok. If it's any darker than the color of straw, you're probably not drinking enough. Symptoms of dehydration include headaches, loss of concentration and tiredness, dry skin and eyes.

Ongoing dehydration can cause problems with, among other things, your kidneys, liver, joints and muscles. Many people are unaware that they are dehydrated, they simply become used to not feeling 100%.

You should drink throughout the day, rather than when your body cries out for liquid. From a vanity point of view - hydrated skin looks younger as its plumper, dehydrated skin looks sallow and older. Just by drinking more water could make you look years younger.

How much do we need?

The Food Standards Agency and The British Diabetic Association recommend that people living in the UK (or a country of similar climate) drink six to eight glasses of water every day. That's about one and a half to two liters, or a big bottle of water. Children will not need as much water as adults. This is based on an average day in Britain, when the weather heats up, or you have done a lot of exercise, you will need to drink more.

Remember to stick to the daily recommended limit, as drinking too much water can be just as damaging. Too much water could lead to water intoxication, which could be fatal.

To find out a more accurate water intake, try Water Aid's online hydration calculator. It calculates the amount of water you need to drink, based on your weight and amount of exercise you do each day.

What if I don't like water?

The most effective way to drink enough and stay hydrated is to drink plain water, a fizzy drink only contains about 65% water. If you really don't like water, try diluting it with a little pure fruit juice.

The Food Standards Agency also recommends drinking semi skimmed milk. If you're also drinking tea and coffee, it's worth remembering that the caffeine in them acts as a diuretic, which means you will want to urinate more, so drink a little more to compensate. As for alcohol, this does not count, as it dehydrates you. So if you like your booze, you will need to top up your water intake.

How can I drink more?

Start each day with a glass of water, adding a squeeze of lemon or lime to give your digestive system a boost. Keep a bottle of water with you, in your bag / briefcase.

Keep a bottle of water on your desk and drink as you work. Eat more fruit and vegetables; they have a higher water content, than most other foods. Drink a glass of water at set points during the day, one before lunch, one before you leave work, one as you get home etc... Have a glass of water every time you have a cup of tea or coffee and every time you eat.

Plumbed in water cooler, Bottled or tap water?

Plumbed in water coolers and bottled coolers, is big business these days. Many of us find that the water that comes from the taps does not taste very nice, so using a water cooler or buying bottles, seems like a logical solution.

So a good option is to invest in a water filter. The filtering process lowers the lime-scale content of the water, plus it reduces other substances that can effect the smell and taste of water, such as chlorine.