Dehydration occurs when you use or lose more fluid than you take in, and your body doesn't have enough water and other fluids to carry out its normal functions.
Mild dehydration can easily be treated but if it reaches extreme levels, it can be life-threatening and will require immediate medical attention.
It's important to increase water intake during hot weather, when exercising, during pregnancy or when you're ill. For more on how much water you need to drink each day read this.
What are the symptoms of dehydration?
If you simply rely on thirst as an indicator of your body's need for water, it will be too late because the process of dehydration starts even before we begin to feel thirsty.
The signs and symptoms of dehydration may differ by age.
Infant or young child
Dry mouth and tongue
No tears when crying
No wet diapers for three hours
Sunken eyes, cheeks
Sunken soft spot on top of skull
Listlessness or irritability
Less frequent urination
Dehydration can lead to serious complications, including:
Heat injury. If you don't drink enough fluids when you're exercising vigorously and perspiring heavily, especially when in the hot sun, you may end up with a heat injury, ranging in severity from mild heat cramps to heat exhaustion or potentially life-threatening heatstroke.
Urinary and kidney problems. Prolonged or repeated bouts of dehydration can cause urinary tract infections, kidney stones and even kidney failure.
Seizures. Electrolytes — such as potassium and sodium — help carry electrical signals from cell to cell. If your electrolytes are out of balance, the normal electrical messages can become mixed up, which can lead to involuntary muscle contractions and sometimes to a loss of consciousness.
Low blood volume shock (hypovolemic shock). This is one of the most serious, and sometimes life-threatening, complications of dehydration. It occurs when low blood volume causes a drop in blood pressure and a drop in the amount of oxygen in your body.
Decreased exercise performance is impaired when an individual is dehydrated by as little as 2% of body weight. Losses in excess of 5% of body weight can decrease the capacity for work by about 30%.
How to Prevent Dehydration
Since dehydration can be a life-threatening condition, it is important that you replenish your body with water immediately. Water plays such an immense role in your bodily functions, making it an essential part of your everyday life and everyone is at risk for dehydration, even without any physical activity.
Always bring a bottle of water with you during exercise or any physical activity, especially when the temperature is high. One good rule of thumb to prevent dehydration is to drink as much water as needed until your urine turns light yellow. Dark urine means that your kidneys are retaining liquids in order for your body to perform its normal functions.
It is especially important to keep water intake high when you are sick with fever, vomiting, or diarrhea.
Remember that a healthy person urinates seven to eight times each day, so if you're not urinating frequently it means that you're not drinking enough water.