10 Essential Facts About Heat, Sweat, and Your Health | Everyday Health

In all weather conditions, the body works hard to maintain a normal temperature of 98.6 degrees. When temperatures are drastic, whether it’s a scorching summer day or a frigid winter morning, it can be even more difficult for your body to maintain this ideal temperature.

“Even at rest, the human body produces a lot of heat energy,” says Eric Buete, MD, the medical director of AFC Urgent Care in Sarasota, Florida. When it’s cool, your body will expel this heat through radiation. “The heat simply radiates from the body to the surrounding air,” explains Dr. Buete.

热的时候,你的身体出汗to keep you cool. Perspiration comes to the surface of your skin. As it evaporates, you begin to feel cooler, according toHouston Methodist. When it’s humid outside, it’s harder for the perspiration on the surface of your skin to evaporate, because the air is already saturated with moisture. That’s why people often say it’s not the heat but the humidity that makes it unbearable to be outside on a hot day — though both play a role in your body's overheating.

In other cases, sweat may occur without an external trigger at all.

Knowing whether you’re at a higher-than-usual risk for heat-related illness, as well as what may be behind your symptoms, can help you know what action to take.

This list of fast facts is a good place to start.

1. Extreme Heat Is Dangerous — and Sometimes Deadly

In a typical year, about 618 Americans die from extreme heat, according to theCenters for Disease Control and Prevention (CDC). Seniors, young children, and people with mental illness and chronic conditions likeheart diseaseare at highest risk, the CDC says, and athletes, outdoor workers, andpeople in the Black, Indigenous, and People of Color (BIPOC) communities are particularly vulnerable.

2. Men Sweat More Than Women

While women have more sweat glands than men, according to theU.S. National Library of Medicine, men's sweat glands are more active, leading them to sweat more than women. The more you sweat, the more easily you can becomedehydrated, which can lead to other health issues, Buete says.

RELATED:6 Unusual Signs of Dehydration

3. You Have Up to 4 Million Sweat Glands in Your Body

That’s according to theInternational Hyperhidrosis Society. There are two types of sweat glands: eccrine and apocrine. Both produce fluids. The area of the brain known as the hypothalamus controlsyour body temperatureby regulating sweat output and blood flow to the skin. The odor associated with sweat comes from the apocrine glands found in the armpits and genital region; the sweat from these glands produces a smell when it comes in contact with bacteria on the skin.

4. Heat Exhaustion Occurs When Your Body Overheats

Warning signs ofheat exhaustioninclude: dizziness,nausea,vomiting, fatigue, heavy sweating, and headache, notes the疾病预防控制中心. To treat heat exhaustion, move to a cool location, drink lots of water, and soak in a cool bath or use cool compresses.

5. Being Overheated Can Lead to Heatstroke, a Life-Threatening State

Heatstroke can occur when your body temperature reaches at least 104 degrees; at this point, your body loses the ability to regulate temperature on its own, according to theAmerican Academy of Family Physicians (AAFP). Signs ofheatstrokeinclude muscle cramping, a fast heartbeat, vomiting, flushed skin, headache, mental confusion, and seizures, per the CDC. Call 911 if you see someone experience these symptoms. As with heat exhaustion, someone experiencing heatstroke should be moved to a cooler place and given a bath of cool water or compresses.

6. You Can Protect Yourself From Heatstroke by Staying Hydrated

“Drink before you are thirsty,” Buete says. In extreme heat, it’s best to avoid caffeine and alcohol, the American Academy of Family Physicians advises. Wear loose clothing that allows the air to circulate around you as you exercise, and avoid exercising outdoors during the hottest part of the day, which is often from 11 a.m. to 6 p.m. Instead, schedule your workout as close to sunrise or sunset as possible.

7.Infants and Small Children Are at High Risk of Heat-Related Illnesses

This is true for several reasons, Buete says. They can’t control their environment (if they’re left in a room that is hot, for example); they have a high metabolic rate, which means their bodies are producing heat constantly; and they aren’t able to perspire as much as adults, Buete says. Never leave a child in a parked car, even with the windows open.

8. Certain Groups of Adults Are Also at an Elevated Risk of Illness From Extreme Heat

That includes those who are morbidly obese, the elderly, and people who are immobile, Buete says. People withdiabetescan be heat sensitive, too, says Matthew Corcoran, MD, CDCES, who is the medical director of the Joslin Diabetes Center affiliate at Atlanticare in Egg Harbor Township, New Jersey. “If you have diabetes and you become dehydrated from the heat, it can affect your blood-sugar levels,” says Dr. Corcoran. Be sure to keep insulin and otherdiabetes medicationsout of the heat, as hot temperatures can ruin them, he adds. People with multiple sclerosis may find that their symptoms worsen when they’re hot. When heat raises a person’s body temperature, it becomes harder for the central nervous system to work properly.

9. Some Medications Can Put You at Increased Risk of Heatstroke

These include some kinds ofallergy medicinesand抗组胺药, blood pressure and heart medications,diuretics,laxatives,antidepressants, and seizure medications, according to the AAFP. Talk to your doctor about what precautions are important if you’re taking any of these.

10. About 3 Percent of the Population Has a Health Condition That Causes Excessive Sweating

Calledhyperhidrosis, this condition characterized by overactive sweat glands, which cause profuse sweating, according to theCenter for Sweat Disorders at Johns Hopkins Medicine. This health condition can be inherited or caused by other health conditions or medications, and can occur without a trigger from heat.Treatments for hyperhidrosisinclude oral and topical medications,Botoxinjections, and a procedure that uses electricity to turn off the sweat glands. If these treatments are not effective, you may discuss surgical options with your doctor.

Additional reporting byAngela Haupt.