How Your Body Responds To Heat – Heat Index Explained

How Your Body Responds To Heat

Summer officially started June 21, but if you’ve spent much time outside lately, you could argue it started well before then. The hot temperatures are more than just uncomfortable though; they can be downright deadly. Keep yourself and your loved ones safe this summer with this guide to dealing with the high temperatures and hot conditions.

Know the Threat

The first step in keeping yourself safe is knowing just how the heat affects you. Essentially, your body is constantly trying to regulate its internal temperature and keep it consistent. As it starts to rise, the body responds by trying to release some of that extra heat in two main ways: by sending more blood to the skin’s surface and by sweating. Circulating blood to the skin works to release heat if the air is cooler than the body temperature AND if the skin is exposed to the air. But if the air is too warm or the skin is covered, this method doesn’t work. Sweating is the next method, and it releases heat when the sweat evaporates. If the air is too humid or if you’re wearing tight, water-resistant clothing, the sweat won’t evaporate and your body can start to overheat quickly. Sweating also releases large amounts of fluids and salts, both of which need to be replaced or the body can start suffering dangerous side effects.

Watch Out for Those at Greatest Risk

When the heat gets extreme, anyone can be at risk of heat-related illnesses. However, some people will be in greater danger.

The very young (0-4 years old) and the elderly (65+)
People who are dehydrated, from not drinking enough water, or from binging on alcoholic or caffeinated drinks
People with medical conditions, such as heart disease, fever, obesity, mental illness, or poor circulation
People with a sun burn, which can cause damage itself and also make it more difficult for the body to regulate heat
People taking certain prescription drugs; check with your doctor.

Understand the Effect of Humidity

Heat illness isn’t just a product of high temperatures. Humidity levels can make it seem hotter than a thermometer says it is. The National Weather Service provides a Heat Index scale to provide a better indication of what the weather feels like, and how dangerous it is. As you can see, temperatures in the mid-80s can act like temperatures in the 100s with high levels of humidity.

Don’t Leave Kids in Cars

One of the biggest dangers in hot weather is the inside of cars. The interior of a car with the windows up in 80°F weather can get up to almost 100°F in just ten minutes. Dozens of children die every year from heat stroke due to being left alone in vehicles. Don’t leave children in alone in your vehicle!

Prevent Illnesses

The best advice is to avoid prolonged exposure to hot weather—stay in cool areas during the hottest parts of the day, and move indoors whenever you start feeling the heat. If you must be outdoors in the heat, follow these recommendations:

Drink more fluids than normal
Avoid alcohol, caffeine, and sugary drinks
Use sunscreen rated SPF15 or higher
Wear light, loose-fitting clothes, and if you are going to spend a lot of time in the sun, wear a wide-brimmed hat
DON’T take salt tablets unless recommended by a doctor

Treat the Symptoms

There are four common medical problems caused by too much exposure to the heat: heat rash, heat cramps, heat exhaustion, and heat stroke.

Heat rash is just what the name says: a rash caused by heat. It looks like a red cluster of pimples or small blisters, caused when the skin becomes irritated by excessive sweating. It’s most commonly found where sweat tends to form and have trouble evaporating, including on the upper chest and neck, in the groin, under the breasts, and in elbow creases. The treatment includes:

Moving to a cool place
Dry the area; a drying powder can help ease the irritation
Do NOT wash with water, unless it is toweled off immediately

Heat cramps are a muscle pain, often caused by strenuous activity in hot weather. They’re usually the result of losing too much salt and fluid due to too much sweating. The treatment includes:

Stopping the activity and moving to a cool place
Drinking clear juice or a sports beverage to replace fluids and salts (but do NOT take a salt pill)
Remaining at rest for several hours after the pain goes away
Seeking medical attention if the pains lasts more than one hour after you begin resting

Heat exhaustion is when the body starts breaking down because it can’t control its internal temperature. Symptoms include heavy sweating, paleness, muscle cramps, fatigue, weakness, dizziness, headache, nausea and/or vomiting, and fainting. Also, despite the heat, the skin may feel cool and moist. Breathing will likely be fast and shallow and the heart rate will be fast and weak. It only takes a few of these symptoms to indicate heat exhaustion. It can also come at the start of the day, as accumulation from several days of being in hot conditions along with not enough fluid intake can cause it. The treatment includes:

Stopping activity immediately and moving to a cool place
Taking a cool shower or bath, if necessary
Drinking cool (non-alcoholic!) beverages
Changing into lightweight clothing, if necessary
Remaining at rest for several hours after the symptoms go away
Seeking medical attention if the symptoms get worse while you’re treating them

Heat stroke is the worst of the heat-related illnesses. This is when the body can no longer cool itself, and it begins to break down entirely. Not treating heat exhaustion can lead to it, and the body temperature can rise to 106°F or higher in as little as 10-15 minutes, which can cause damage to vital organs, including the brain. If you expect heat stroke, seek immediate emergency treatment. Not treating heat stroke can cause permanent disability or death. There are several signs that could show heat stroke, though not all of them need to be present:

A thermometer temperature reading 103°F or higher
Red, hot, and dry skin without sweat
A strong, fast pulse
A throbbing headache
Dizziness
Nausea, with or without vomiting
Confusion
Unconsciousness

The treatment is to quickly get the person suffering from it to a cool place and to get emergency medical help. Cool the person down as quickly as possible, usually done by soaking them with cool water.