sealPurdue News

July 1998

Take precautions to keep cool

WEST LAFAYETTE, Ind. -- When the mercury soars outside, using a little common sense and drinking lots of liquids can keep things from getting too hot to handle.

That's the advice from Olivia B. Wood, associate professor of foods and nutrition at Purdue University. Wood works with athletes and teaches them the effects of dehydration and nutrition on the body. A heat wave, with temperatures in the 90s and humidity to match, is cause for concern, she says.

"During a heat wave, it is important to be aware of the symptoms associated with dehydration and loss of body fluids." she says. "If you don't use common sense and prepare yourself, you could face some serious difficulties. Some of them could be fatal."

Wood says that when temperature and humidity are high, the body loses much of its cooling ability. "The body cools itself by the evaporation of sweat from the skin. In really hot and humid weather, sweat doesn't evaporate and the heat is trapped."

Be aware of signs of dehydration, she says. They include heat cramps, heat exhaustion and heat stroke. Heat cramps are signaled by thirst, chills, clammy skin, nausea and a throbbing heartbeat.

"If you experience these symptoms, immediately stop what you're doing and move to a cool location," Wood says. "Consume lots of water or some other cool liquid."

Paying attention to these early signs may prevent the onset of a much more serious condition, such as heat exhaustion or heat stroke, Wood says.

"Heat exhaustion is signaled by reduced sweating, shortness of breath, dryness of the mouth, a weak but rapid pulse, headache, dizziness and extreme fatigue," she says. "Again, drop everything and move to a cool location and consume cool liquids. Also, it is important to employ other methods to cool the body off. Take a cool shower or apply an ice pack to the forehead."

Wood says failure to pay attention to early warning signs may lead to the most serious type of heat stress -- heat stroke. At that point, immediate medical attention is required, because the person is in a life-threatening situation.

"Their temperature will increase dramatically," she says. "Because of severe dehydration, the body's circulatory system and kidneys can shut down."

Cool liquids, which can be easily absorbed from the stomach, are best for preventing and treating the early stages of dehydration, Wood says.

"Water, sodas without caffeine, sport drinks and fruit juices are all good choices," she says. "Plain water is the least expensive and most readily available."

Wood says to avoid concentrated beverages, as they may actually contribute to dehydration.

"Concentrated beverages are beverages that contain high levels of sugar, salt or potassium," she says. "These beverages stay in the stomach until sufficient fluids are drawn in to dilute them" she says. "Also, avoid alcohol and any kind of beverage with caffeine, because they act as diuretics, and increase the loss of fluid from the body."

How do you tell if you are getting enough liquid?

"Strong-colored, strong-smelling urine in small amounts indicates dehydration," she says. "Light-colored urine in normal amounts indicates normal hydration. The average amount of urine expelled per day varies among individuals, but it is usually about one and a half to two and a half quarts."

Wood says heat-related problems are preventable and fairly easy to avoid.

"When it gets hot outside, stay inside if at all possible," she says. "At the very least, stay in a cool place and drink lots of liquids. Use a little common sense, and you won't have a problem when mother nature turns up the heat."

CONTACT: Wood, (765) 494-8238;;

Compiled by Amanda Siegfried, (765) 494-4709; e-mail,
Purdue News Service: (765) 494-2096; e-mail,

* To the Purdue News and Photos Page