University at Buffalo (UB)
Published July 22, 2011 This content is archived.
Even healthy people need to take care to stay cool and hydrated during heat waves, says University at Buffalo professor Richard V. Lee, MD.
“It’s important for everyone to maintain their water-electrolyte balance,” says Lee, professor of medicine, pediatrics, gynecology-obstetrics and social and preventive medicine.
“For that reason, if you are drinking eight to 12 glasses of water per day, you need to make sure that one of those glasses contains Gatorade, or fruit or tomato juice so that you are replacing electrolytes.
“If all you do is drink water, you can dilute the amount of sodium in your blood. When you do that, you don’t sweat as efficiently, which can cause you to stop thinking correctly and lead to fatigue and muscle weakness.”
During heat waves, young athletes should heed their coaches’ advice about resting and drinking, says Lee, an expert in geographic medicine and public health.
“This is the kind of weather that fosters heat stress and heat stroke. That’s when you can’t thermoregulate the way you normally do.
“Normally, our bodies thermoregulate by dilating the blood vessels in our skin and radiating heat. But if you get really dehydrated and your electrolytes become depleted, you no longer have the ability to cool your skin by sweating.
“That’s when people become a sort of hot box—and that’s when heat stroke can occur.”
The elderly need special attention as temperatures rise, Lee says.
“Older people, especially those with medical conditions who are taking medications, should probably check with their family doctors about what they need to do during a heat wave.
“People taking diuretics for blood pressure, for example, will be urinating a lot so they need to be careful about maintaining the water-electrolyte balance. They shouldn’t overdo their salt intake.”
Older individuals with even mild dementia can also lose their ability to sense changes in body temperature, he says.
“They tend to lose the fine touch of their thermal sensing system. Patients in nursing homes or hospitals who are lying in bed, covered with blankets, also can lose the ability to sense temperature changes, and they can become feverish simply because they are too hot.”
Just like the elderly, babies don’t thermoregulate well and can become feverish when they're too hot. In those cases, Lee says, a cool bath and more fluids can be helpful.