Dear Doctors: I'm hoping you will talk about dealing with a heat wave. It's probably something you have covered before, but maybe you would be willing to do a repeat? I'm a counselor at a day camp, and we are seeing how easy it is to get into trouble on a hot day.
Dear Reader: You are correct that we have written about staying safe in extreme heat before. With heat waves being more widespread, frequent and intense, this is an important topic. And as you say, it is easy to underestimate the risks of a hot day. While a heat-related illness can develop easily, it can be hard to reverse it. Once the body's cooling mechanisms are overwhelmed, reversing the process requires swift and specific medical care.
The goal during a heat wave is to keep your core body temperature within a safe range. When internal body temperature climbs too high, it triggers a cascade of changes. This can damage cells and tissues and impair the function of vital organs. Once that process begins, it can be difficult to stop. Simple overheating can quickly progress to heat exhaustion and, in some cases, heat stroke. Here in the United States, heat-related illnesses account for more than 100,000 emergency department visits each year. In 2022, heat-related illnesses claimed more than 1,700 lives.
The guidelines for staying safe are simple: Help your body stay cool by wearing loose, light-colored clothing. Wear a hat or use an umbrella outside. Stay hydrated, preferably with water. Drink throughout the day, even if you don't feel thirsty. Avoid strenuous activity during the hottest part of the day. Seek out air-conditioned spaces when possible. Many communities offer cooling centers for those without AC at home or work.
If you do have to spend time outdoors, be sure to take frequent breaks to rest, drink and cool your body with water. It's important to remember that with every muscle contraction, your body is generating heat. Even ordinary outdoor activities, such as taking a hike, a game of catch or mowing the lawn, add to the body's heat load. This is particularly true when humidity is part of the picture. The higher percentage of moisture in the air means that sweat evaporates slower and also cools slower.
(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
