Dehydration & Heat Illness

While some parts of Utah may not appear like it, Utah is located in a high desert. (Also see our Altitude Illness page.) When low humidity is combined with exertion in the sun and heat, dehydration can be a problem. Dehydration is a condition in which the body or certain body tissues suffer from lack of water. The body normally cools itself by sweating. People suffer heat-related illness when they do not replenish this loss of fluid. Very high body temperatures may damage the brain or other vital organs. Several factors that reduce the body's ability to cool itself during extremely hot weather are: dehydration, age (the elderly and young children), obesity, fever, heart disease, mental illness, poor circulation, sunburn, prescription drug use, and alcohol use.

Summertime activity must be balanced with measures that aid the body's cooling system. These include wearing light, "breathable," loose fitting clothing and drinking plenty of water. Water is the BEST "sports drink" available. However, if you chose to drink one of the many electrolyte replacement drinks available, consider diluting it 1/2 with water. AVOID caffeine drinks since they prevent the body from retaining water. The most common mistake inexperienced outdoor enthusiasts make is to not have any water or enough water with them during summertime activities. (If your pets are with you, don't forget to provide water for them as well.) If you run out of water, DO NOT drink untreated water from streams or lakes no matter how clean/clear the water appears or how remote the location. Drinking untreated water can cause Giardiasis (GEE-are-DYE-uh-sis) - see the CDC link below for a complete explanation of this condition. Portable water purifiers or water purifying tablets can be purchased from any outdoor recreational store.

Thirst is the earliest indicator of dehydration. Therefore, if you wait to drink until you feel thirsty, you are probably already dehydrated.
A good rule of thumb is to take at least 3 swallows of water every 15 minutes - whether you are thirsty or not. That means you need at least 12 swallows of water for every hour of activity (be careful not to underestimate how long your activity will take).

If you ignore your thirst, you could begin to experience the following symptoms:
• Headache, dizziness, light-headed, fainting
• Dry mouth and nose
• Heavy sweating
• Paleness
• Muscle cramps
• Weakness
• Nausea or vomiting

If you begin to experience any of the above symptoms:
- Stop all activity and sit quietly in a cool place out of the sun.
- Drink water even if you have to force yourself.
- Seek medical attention if these symptoms do not subside in 1 hour.

If you ignore these symptoms and your body temperature continues to rise, you could begin to experience these symptoms: rapid breathing, no perspiration, eyes that are sunken and dry, drop in blood pressure, muscles spasms, and disorientation. This is now a life-threatening situation where immediate medical care is necessary.

In almost every case, heat related illness/injuries could be avoided through the prevention of dehydration and common sense practices.

The information provided here is designed for educational use only and is not a substitute for specific training or experience. Much more dehydration information and safety tips can be found here:

Center for Disease Control (CDC) Extreme Heat site with links
National Library of Medicine Dehydration site with links
Children and dehydration
CDC discussion of giardiasis
American Cancer Society Sun Safety site
CDC Sun Safety site

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