What to Know About Sweating

Medically Reviewed by Stephanie S. Gardner, MD on February 22, 2024
3 min read

Everybody sweats — some a little, some a lot. You probably already know that your body sweats as a way to cool down when you’re hot or exerting yourself. But do you know what’s in sweat? And can you really sweat out toxins? Here’s everything you need to know about sweat and sweating.

Your body’s ideal temperature is around 98.6 degrees Fahrenheit. This number can vary a bit from person to person, but this is the average core temperature. If your body gets too hot, your brain sends a message that the body needs to cool down. This message comes from the hypothalamus, the part of the brain that controls your body’s temperature. To cool down, your body begins to release sweat.

Sweat comes from glands in your skin that can be found all over your body. You have higher numbers of sweat glands on your forehead, armpits, the palms of your hands, and the soles of your feet. These glands release sweat so that, as it evaporates, your body temperature falls.

Some normal sweating causes include:

  • Exerting yourself while exercising
  • Heat, like hot temperatures in the summer 
  • Eating spicy foods
  • Stress, anxiety, or nervousness
  • When you’re sick and have a fever

Overheating is dangerous, so if we didn’t sweat, we’d die.

Sweating when you’re stressed or anxious is thought to be an ancestral trait in early humans that was needed for hunting animals or fighting off attackers. When you’re nervous, your palms and feet sweat more, which can help to improve your grip. This is because the sweat that’s released when you're nervous helps to control humidity and friction on your skin. This could have helped early humans when it came to using tools or weapons.

Sweat is made up of mostly water. A small portion of your sweat contains other things, including:

  • Electrolytes like sodium, potassium, calcium, and magnesium. Electrolytes help to trigger different necessary responses in your body, so it’s important to replace them after periods of heavy sweating.
  • Small amounts of pheromones, which are chemicals that act like hormones outside of your body
  • Bacteria that grow in the sweat that you release; this bacteria can cause body odor.
  • Tiny amounts of toxins

Sweating is an important function when it comes to your health. Sweating cools down your body through heat vaporization, the process of sweat drying off your skin. It’s a highly effective way to cool down. But sweating causes you to lose water. Your body is made mostly of water, so we need to replace it after periods of heavy sweating.

Dehydration can happen after intense exercise or from being out in hot, sunny weather. This kind of dehydration can happen to both children and adults who don’t drink enough water to replace the liquid that they are sweating out.

Sweating dehydration can be tricky because you might not feel thirsty until you’re already too low on fluids. When you’re exercising or out in hot weather, it’s important to keep drinking water, even if you don’t feel especially thirsty, to avoid dehydration. 

Not drinking enough water after sweating a lot can also lead to heat injury. This type of injury can range from mild cramps to heatstroke, which can be deadly.
 

Can I Sweat Out Toxins That Are in My Body?

In a word, no. You may have heard that sitting in a sauna or going to a hot yoga class will help your body sweat out dangerous toxins. But your sweat is 99% water. Trace amounts of metals and other chemicals can be present in your sweat, but your kidneys and liver do most of the work when it comes to getting rid of toxins in the body.

What you eat has a bigger impact when it comes to getting rid of toxins in the body. Good nutrition helps your organs to function well. Organs and systems like the urinary, fecal, and respiratory routes do most of the heavy lifting when it comes to detoxification, so these systems need proper fuel to get the job done.

You might notice that your sweat has a strange smell after you eat certain foods. Some sulfuric vegetables, like cauliflower, cabbage, and garlic, can change the smell of your sweat.