Hints and Tips

How much water may the body lose in one day?

The typical adult living in a temperate climate loses about 2-2.5 litres of water per day in things such as expired breath, sweat, urine and other bodily secretions. The total quantity will depend on gender, body size, weather, clothing worn, activity levels and a whole range of other factors.

We lose water constantly, but drink only intermittently, so the water content of the body is constantly changing.

For the average 80 kg male sitting at rest in a comfortable environment, water losses will typically run at about 300 mL per hour. For the average female who weighs about 65 kg, losses will occur at a slightly slower rate of about 250 mL per hour.

If we accept that a dehydration level of about 1% of body weight is tolerable, that could occur after only about 2-3 hours. So long as we drink adequate amounts at meal times, and at the typical tea/coffee breaks that most of us have, we can stay perfectly well-hydrated throughout the day.

About to take a plane? It is important to know how to stay hydrated

The body tends to dehydrate while travelling, particularly on aeroplanes because air in the cabin is usually much dryer than than the air on earth. When traveling, hydration levels can be maintained by drinking an additional 250 mL per hour.

What's the weather forecast for today? The weather affects hydration needs

Sweating or perspiring is a skin-cooling system that uses a great deal of water. That's why sweat losses have to be replaced when we are exposed to high temperatures, such as in the summer or in any other hot environment. It is important to keep an eye on the weather forecast, temperature and humidity in the city or region we live in or we are visiting in order to adjust hydration levels accordingly.

We have to know how to read the signals our body sends us

The colour of urine is one of the best ways to recognize dehydration. Straw coloured urine indicates a good fluid intake. It is important to keep an eye on the colour of urine. The darker it is, the more you may need to drink.

This chart can be used to check urine colour. If the colour is dark, it may indicate a need to drink more. If the urine is completely colourless, it may indicate too much fluid intake.