When you use or lose more fluid than you take in, this causes dehydration.
Symptoms of dehydration include the following:
- Little or no urine, or urine that is darker than usual
- Dry mouth
- Sleepiness or fatigue
- Extreme thirst
- Dizziness or lightheaded feeling
- No tears when crying
Your body depends on water to survive. Every cell, tissue and organ in your body needs water to work correctly. For example, your body uses water to maintain its temperature, remove waste and lubricate joints. Water is needed for good health.
Water makes up more than half of your body weight. You lose water each day when you go to the bathroom, sweat and even when you breathe.
You lose water even faster when the weather is really hot, when you are physically active, or if you have a fever. Vomiting and diarrhea can also lead to rapid water loss. If you don't replace the water you lose, you can become dehydrated.
Thirst is not always a reliable indicator, especially in children and older adults. A better gauge is the colour of your urine. Clear or light-coloured urine means you are well hydrated - dark yellow / amber usually signals dehydration.
Simple causes of mild dehydration include being busy, travelling or simply forgetting to drink water. A good habit is to always carry a water bottle or container with you and replenish regularly.
Common causes of moderate to high dehydration include vigorous exercise (especially in hot weather); diarrhea and vomiting; and fever or excessive sweating.
Not drinking enough water during exercise or in hot weather, even if you're not exercising, may also cause dehydration.
Anyone can become dehydrated if they lose too many fluids but those more at risk are young children, senior adults and people with chronic illnesses.
Don't wait until you notice symptoms of dehydration to take action. Actively prevent dehydration by drinking plenty of water.
If you work or exercise outside in hot and humid weather, your risk of dehydration and heat illness increases. When the air is humid, sweat cannot evaporate and cool you as quickly as usual, so your body temperature increases and requires more fluids.
Generally, adults are advised to drink 2-3 litres of water each day to be adequately hydrated, more for extreme athletes and in hotter weather.
This summer, prevention is your safest approach to avoid dehydration. Be mindful of how much fluid you lose during hot or humid weather, illness or exercise and drink enough liquids to replace what you have lost.
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