Water"Obey your thirst," the Sprite soft drink commercial demands. They’ve got the right idea, but in reality, avoiding your thirst altogether would be even better. Thirst signals that you are dehydrated, and even mild dehydration can sap your energy and turn a fun hike into an ordeal.

Dehydration happens when your body does not have enough water as a result of heavy sweating, hard exercise, or sickness. It is especially likely to occur if you are hiking in hot weather and direct sunlight, though any time you are exercising hard and sweating a lot, you risk becoming dehydrated.

Preventing Dehydration
It is a lot easier to stay hydrated than to reverse dehydration, because if you are sweating heavily and become dehydrated, you may be losing water faster than your body can absorb the liquid you drink. In order to prevent dehydration, which can cause life-threatening shock in severe cases, it is vital to replenish both the water and the electrolytes (salts) that your body loses through sweat.
  • Carry two to four quarts of water when hiking and sip it throughout the day.
  • Be sure urine is “clear and copious,” an important indicator of good hydration.
  • Eat salty snacks too (or sip sports drinks) to replenish your body’s lost electrolytes.
  • Pay attention to environmental conditions and try to avoid direct sun. In very hot weather, hikers typically lose around one half to one quart of fluid per hour, according to Grand Canyon National Park Hike Smart guidelines.
  • Watch babies, small children, and older adults closely for signs of a dry mouth, reduced urine output, and dark yellow urine, as they are at a higher risk for dehydration.
  • Treat water that you get from wilderness sources; serious illnesses can be contracted from untreated water.
  • Avoid caffeinated beverages, soft drinks, and alcohol; these drinks sap your body’s fluids.
The medical Website WebMD cites thirst as an important early indicator of dehydration, along with dark yellow or brown urine. For mild or moderate dehydration, additional symptoms include:
  • Irritability.
  • Lightheadedness that is relieved by lying down.
  • Dry mouth.

Severe dehydration can be very serious if a person begins to go into shock. Severely dehydrated people may be anxious; confused; faint or sleepy; have a weak, rapid pulse; and cold clammy or hot dry skin. They may even lose consciousness.

When treating mild or moderate dehydration, slowly try to replace lost fluids while halting further loss of fluid from the body.
  • Get victims out of direct sunlight and out of the heat if possible, and remove excess clothing to reduce sweating.
  • Have them drink water or a sports drink to replenish their body’s fluids.
  • Encourage them to rest and to continue drinking fluids.
  • Monitor victims’ symptoms and ensure that they do not show signs of more severe dehydration.

For severe dehydration, get emergency treatment.

Photo: Kevin D. Talbot