Everyone sweats, and it's a good thing we do. Without the ability to cool off through perspiration, our bodies couldn't release heat and we would die. For most people, sweating is an everyday part of life that accompanies activities like going for a run, playing a game of basketball, having sex or speaking in public. 

For others though, sweating happens for inexplicable reasons or lasts longer than it seems it should. "Some people sweat a lot and some people hardly sweat at all," says Kayla Itsines, a certified personal trainer, fitness author and co-founder of the popular fitness app, SWEAT.

Understanding what causes us to sweat and why some people sweat more than others can be helpful. 

What causes sweat?

Sweating is simply the body's response to either being hot or feeling nervous or frightened. Per Mayo Clinic, when one is hot or exercising, the body's nervous system triggers one's sweat glands in an attempt to cool the body back down. This process "allows our bodies to cool via evaporation," explains Anthony Beutler, MD, an associate medical director of sports medicine at Intermountain Health in Salt Lake City. "Evaporation via sweating is the most important cooling mechanism for many mammals, including us," he adds.

Sweating also occurs when one feels nervous or frightened. In such a state, it's a response to the body releasing adrenaline and cortisol – hormones related to stress.

Why do I sweat so much?

In most cases, sweating - even a lot at a time - is normal, especially when enduring high temperatures or during extended periods of exercise. But sometimes excess sweat is caused by other conditions or factors. According to Stanford Medicine, these include things like having a reaction to certain medications, teens going through puberty as their sweat glands grow along with the rest of their body, illness, women experiencing menopause or conditions such as diabetes, obesity or an overactive thyroid. 

Itsines notes additional factors that impact one's amount of sweat include "things like genetics, climate, age, gender, metabolism, sickness and clothing." Another cause of excessive sweating is a condition known as hyperhidrosis − when the body sweats more than it needs to and sometimes for no apparent reason. 

When should I be concerned about sweating?

Though in most such cases, sweating still isn't something to be alarmed about, there are few times in which sweating can be a symptom of something worrisome. 

Mayo Clinic warns to seek medical attention when sweating is accompanied by dizziness, cold skin, a rapid pulse, or pain in the chest, throat, jaw or arms. The combination of such symptoms could be related to having a panic attack, high fever, a heart attack or different conditions related to heart disease. 

Short of perspiration being a symptom of something serious, however, if find yourself sweating more often or more heavily than you think you should, the experts recommend consulting a physician who may suggest special antiperspirants, therapies or medications.

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