In recent weeks, high temperatures have been recorded in Mexico and the United States. The Mexican National Meteorological Service (SMN) warned that This May 20th began the third Heat wave it’s from the season.

In 2023, they registered record temperatures on three different continents. The United States saw the highest number of heat warnings ever recorded, parts of China were simultaneously warming, and temperatures in Europe soared so high that residents unofficially dubbed the heat wave Cerberus, after Dante’s monster from Hell.

Thanks to climate change, these scorching records are likely to be surpassed soonhence It is important to understand the ways heat damages the human body and how to prevent themsays Kurt Shickman, director of extreme heat initiatives at the Adrienne Arsht-Rockefeller Foundation Resilience Center in Washington, DC. “The heat is extremely dangerous, and climate change will make more areas vulnerable,” he admits.

That extreme temperatures can damage (and sometimes they can even be lethal) involves numerous factors. The thermometer is key, of course, but humidity also mattersbecause humans cool our bodies mainly through the evaporation of sweat.

Although this technique works well in the dry African savannahs where humans evolved, it is much less effective in the swampy areas of Washington, D.C., subtropical southern Florida, and many other parts of the United States, says W. Jon Williams, an expert in heat health from the National Institute for Occupational Safety and Health of the Centers for Disease Control and Prevention.

It doesn’t take long for heat to damage the body, so recognize the signs of heat illness (and know the measures to take) can save lives.

Heat rash consists of small blisters similar to grains They come out when sweat trapped under tight clothing cannot evaporate and pores become clogged. It usually appears on the chest, neck and/or armpits when the shirt is tight, or around the breasts or groin if the bra, shorts or underwear are tight.

Heat rash differs from sunburn in that it it is not necessary Sun exposureand the blisters are usually not dangerous.

As soon as the rashes are detected, you must Move to a cool environment and remove offending clothing. Place cold compresses on the skin can speed healing. Most cases resolve within hours, but if redness or pain persists, or if a fever develops, the area may have become infected and require antibiotics.

Heat cramps are painful, involuntary spasms that occur after strenuous outdoor activity. They’re an early sign that the body isn’t coping well with the heat, says Kristopher Paultre, a sports medicine doctor at the University of Miami.

The cramps They are triggered when intense sweating causes the loss of important electrolytes; A sudden drop in sodium, potassium, and calcium can trigger involuntary contractions. The muscles most prone to cramps are those that are activated during a person’s activity. “If you run in the heat, you’re more likely to get leg cramps,” says Williams. Each cramp lasts several minutes.

To put an end to cramps (and make sure they don’t turn into more serious heat illnesses) you need to stop exertion and move to a cool place. Lost sodium is better recovered eating salty foods I eat French fries, but not taking salt pills, an old folk remedy. According to the expert, these pills carry liquids to the intestine and remove them from the cardiovascular system, already overloaded by the heat.

A adequate hydration can prevent cramps by heat. Drinking plain water is sufficient if outdoor activities are scheduled for two hours or less, as the body self-regulates electrolytes during that time (including capturing minerals secreted in sweat and returning them to the blood). They must then be consumed electrolyte sports drinks that contain these minerals.

Heat exhaustion is occurs when the body’s efforts to maintain its standard temperature of 37 °C they start to falter. During an episode of heat exhaustion, body temperature can reach 39°C, and the symptoms are much more severe than muscle cramps.

Some symptoms of heat exhaustion stem from the body’s increasingly frantic effort to lower its temperature: sweating intensifies and diuresis decreases to accumulate liquids. Intense fatigue or even fainting occurs to force rest.

“If you’re working hard in a hot environment, you’re generating a lot of metabolic heat on top of the high ambient heat. “If you take off one of the burners, your body isn’t going to be as hot,” Williams explains.

Furthermore, electrolytes become increasingly depleted (causing headaches and dizziness) and higher body temperature promotes nausea and irritability.

To treat heat exhaustion you must move immediately to a cool place (ideally with air conditioning), drinking water and quickly lower your body temperature by taking a shower or a warm bath or placing ice packs on your torso. During many college athletic tournaments in Florida, ice buckets are kept ready in case overheated players need to dunk, Paultre said.

Once core temperature has recovered, most people do not need medical attention. People with heart disease, however, might want to go to the emergency room to make sure they haven’t been hurt, Williams advises.

For 1 in 10 people who suffer from it, either because they continue with their physical activity or because circumstances prevent them from getting relief, their condition quickly turns into heat stroke, says the specialist.

He heatstroke occurs when the body can no longer control its internal body temperature, which rises to 40 °C or more. The skin becomes red and hot to the touch, and sweating stops. “At this point, the body has stopped trying to cool itself. He has given up,” says Paultre.

This condition is so serious that it can kill up to 65% of people who reach this state. The classic cases are an elderly person without air conditioning who dies after days of incessant heat and humidity, or a child abandoned in a closed car who perishes in a matter of minutes.

Outdoor workers and athletes suffer exertional heat stroke. In this case, an organism forced to choose between keeping the heart and muscles functioning or reducing the high body temperature usually gives priority to the former.

Men, more likely to work outdoors, account for more than two-thirds of heat deaths in the United States. The European heat wave of summer 2022 was fatal to 61,000 people, mostly young men and older women, scientists concluded.

High body temperatures affect the central nervous systemcausing delusions, seizures and often, loss of consciousness. Clots form in the cardiovascular system and inflammation spreads throughout the body, damaging the kidneys, heart and other organs.

A person suffering from heat stroke is unable to help themselves. He only survives when those around him They call the emergency, take her away from the heat and spray her body with ice and/or cold water. (Forcing them to drink is not advisable, Williams clarifies, since fluid levels should be evaluated by professionals.)

Those who recover often suffer permanent damage in the organs.

“Someone who suffers from heat stroke will spend a lot of time in the hospital,” says the expert. What’s more, your body will likely have difficulty regulating temperature for months or longer, making protective measures against future heat even more important.

People can protect themselves from extreme heat with measures such as spend at least part of the scorching days in an air-conditioned environment (local governments often open cooling centers for residents without access to air conditioning), stay in the shadow when they are outdoors, avoid making efforts (whether for work or sport) in the hottest hours of the day; and secure a adequate hydration.