There is a lot of misinformation about sweat circulating in popular culture today. Many people claim that sweating can clean the body of unwanted toxins and increase a person’s health. While sweating can be a good thing, it is not necessarily the detoxifying cure that some would lead you to believe.

Why People Sweat and What is Normally in it?

It is important to understand thathumans sweat almost exclusively to maintain thermoregulation. Thermoregulation is the process the body uses to maintain its internal core temperature. Sweat works with body temperature in an intricate balance to keep the body from becoming too hot, not as a way for the body to rid itself of toxins. However, the body does lose certain metabolites when it sweats. Most of the sweat the body produces is lost through eccrine sweat glands, which most of the surface of the skin. The sweat that eccrine sweat glands produce is made up of 99 % water and a few other metabolites including: waste products from the blood like sodium chloride, urea, uric acid, proteins, and immunoglobulins.[1] So, what your body loses when it sweats is primarily water and some waste products from your bloodstream. However, the body also loses certain electrolytes, which are salts like potassium, calcium, magnesium, and sodium chloride, as well as some water soluble micronutrients.[2] In a way, the waste products like urea and uric acid that are lost in sweat can be thought of as toxic - but they are normal bodily waste products that are also excreted in much higher concentrations through urination.

Do Toxins Come Out When You Sweat?

Maybe, a little bit. However, they are produced in such low amounts that the impact of sweating out toxins is negligent when it comes to a person’s health. Some of the typical chemicals people think of as toxins are pesticides, flame retardants, and PCB’s, among others. It is also interesting to note that these chemicals are not actually toxins, which are naturally occuring poisons made by plants and animals, but toxicants. The reason that these toxicant levels are so low in sweat is because most of them are not water soluble, and sweat is made primarily of water. Many of these substances tend to be stored in fat molecules in the body. Most of the toxins and toxicants that build up in the body are processed and eliminated by the liver and kidneys, which function for that specific purpose, unlike sweat.[3] Some studies have found that troubling levels of BPA’s, which were commonly used in the manufacturing of plastics, are found in sweat.[4] This is because BPA’s are more water soluble than most other toxicants. There are more effective ways to get rid of BPA’s that have built up in a person’s body than by sweating, however, and it is more highly concentrated in urine anyways.[3]

So, yes, you do sweat out “toxins”, specifically blood waste products and BPA’s (if you’ve been exposed), but sweating toxins out is not an effective way to rid your body of these substances. Using a sauna to sweat out toxins and detoxify is much less effective than simply drinking more water and giving your kidneys some extra liquid to work with. Unfortunately, this also means that for people with hyperhidrosis, who sweat excessively, they probably aren’t any less like to have toxins in their bodies than anyone else.

Sources
  1. Huddle, J. R. (2014). Hyperhidrosis: Causes, Treatment Options and Outcomes. New York, NY: Nova Science.
  2. Popkin, B. M., D'anci, K. D., & Rosenburg, I. H. (2010). Water, Hydration and Health. Nutr Rev.,68(8), 439-458. doi:10.1111/j.1753-4887.2010.00304.x
  3. Engelhaupt, E. (2018, April 6). Fact or Fiction: Can You Really Sweat Out Toxins? National Geographic.
  4. Genius, S. J., Beesoon, S., Lobo, R. A., & Birkholz, D. (2012). Human Excretion of Bisphenol A: Blood, Urine, and Sweat (BUS) Study. J Environ Public Health. doi:10.1155/2012/185731