What is sweat made of?

What is sweat made of?

Sweat is made up of mostly water.

Sweat is about 99% water. The remaining 1% is made up of electrolytes and tiny amounts of minerals:

  • sodium
  • chloride
  • calcium
  • potassium
  • magnesium
  • zinc
  • iron
  • copper

Losing water through sweat is one of a few reasons your body weight can fluctuate throughout the day.

If you weigh less after you exercise, it does not mean you’ve lost fat. It means you’ve lost water (through sweating) and need to replace the water you’ve lost.

The same is true if you lose weight after sitting in a sauna or after getting a body wrap. The weight you lose is not from fat, and will come back once you rehydrate. How to stay hydrated.

Williams, M.H. 2005 Nutrition for Health, Fitness & Spor (7thec.). Boston: McGraw-Hill Higher Education.
ACSM Position Stand: Exercise and Fluid Replacement
Beth Stover and Bob Murray. Drink Up! The Science of Hydration. ACSM’s Health & Fitness Journal. March/April 2007

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Stephanie Averkamp

About the Author was created by Stephanie Averkamp, a recognized health and fitness professional and sole-author of the content on this website. Stephanie's approach to weight loss emphasizes making small, realistic, and permanent lifestyle changes. Read more...

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