Published on August 13, 2010

Stay Cool in the Heat Wave

When temperatures soar, be good to your body and drink up

Feeling thirsty? Too late—you're already on the road to dehydration. "The key to beating the heat is to stay hydrated before the warning signs sneak up," says Ben Sill, MD, TRCH Emergency Department physician.

Heat Exhaustion Versus Heat Stroke
Heat illness occurs when high temperatures and humidity cause the body to lose salt and fluids more quickly than they are replaced. There are two levels of heat illness: heat exhaustion and heat stroke.

Heat exhaustion is marked by excessive sweating, changes in urine color, and a general feeling of weakness. Dr. Sill says act fast, by drinking plenty of water, resting in a cool spot, and draping your head, face, and neck with cool washcloths.

Heat stroke is a medical emergency. Symptoms include nausea and vomiting, headache, inability to sweat, and mental confusion. "Anyone showing signs of heat stroke should seek immediate medical attention," Dr. Sill advises.

Summer Culprits
Beware these common contributors to heat illness.

• Alcohol. Summer recreation and cocktails are a poor mix. Alcohol has a dehydrating effect, especially when it replaces water or other fluids as your cup of choice.
• Swimming. Just because you're wet doesn't mean you're hydrated. "People lose a lot of fluid when swimming because they don't notice how much they're actually sweating," says Dr. Sill.
• Lack of air conditioning. High indoor temperatures can quickly sap your energy. Run a fan, seek relief in air-conditioned public places, and drink plenty of fluids.
• Strenuous activity. Athletes and people working in hot conditions are especially susceptible to heat illness. "If you have profound sweating and you're not stopping to drink, the body won't be able to keep up," Dr. Sill explains.
• Chronic health problems. Medications or underlying conditions such as heart disease or diabetes "can often blind people to the initial effects of heat exhaustion," says Dr. Sill.

Better Beverages
Good old H2O is vital to keeping the body in balance. But surprisingly, when thirst peaks in the heat, Dr. Sill suggests that nature's nectar may not be enough. "If you're exercising heavily, it's important to drink not just pure water but fluids that replace some of the body's electrolytes," he says. Some new sports drinks offer needed replenishing power with less sugar than their predecessors. In periods of intense activity, Dr. Sill advises drinking as much as a quart of fluid every 20 to 30 minutes.