CausesBy Mayo Clinic staff
The cause of sweating and body odor stems from your body's temperature regulation system, specifically your sweat glands. Sweating helps maintain your body temperature, hydrates your skin and balances your body fluids and electrolytes, chemicals in your body such as sodium and calcium.
Your skin has two types of sweat glands: eccrine glands and apocrine glands. Eccrine glands occur over most of your body and open directly onto the surface of the skin. Apocrine glands develop in areas abundant in hair follicles, such as on your scalp, armpits and groin and open into the hair follicle just before it opens onto the skin surface.
When your body temperature rises, your autonomic nervous system stimulates the eccrine glands to secrete fluid onto the surface of your skin, where it cools your body as it evaporates. This fluid (perspiration) is composed mainly of water and salt (sodium chloride) and contains trace amounts of other electrolytes — substances that help regulate the balance of fluids in your body — as well as substances such as urea.
Apocrine glands, on the other hand, secrete a fatty sweat directly into the tubule of the gland. When you're under emotional stress, the wall of the tubule contracts and the sweat is pushed to the surface of your skin where bacteria begin breaking it down. Most often, it's the bacterial breakdown of apocrine sweat that causes an odor.
- Smith CC. Idiopathic hyperhidrosis. http://www.uptodate.com/home/index.html. Accessed Sept. 29, 2010.
- Mauro TM, et al. Biology of eccrine, apocrine, and apoeccrine sweat glands. In: Wolff K, et al. Fitzpatrick's Dermatology in General Medicine. 7th ed. New York, N.Y.: The McGraw-Hill Companies; 2008. http://www.accessmedicine.com/content.aspx?aID=2956361. Accessed Oct. 14, 2010.
- Fealey RD, et al. Disorders of the eccrine sweat glands and sweating. In: Wolff K, et al. Fitzpatrick's Dermatology in General Medicine. 7th ed. New York, N.Y.: The McGraw-Hill Companies; 2008. http://www.accessmedicine.com/content.aspx?aID=2985825. Accessed Oct. 14, 2009.
- Morelli JG. Disorders of the sweat glands. In: Kliegman RM, et al. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa.: Saunders Elsevier; 2007. http://www.mdconsult.com/das/book/body/108020522-2/761896310/1608/1544.html. Accessed Oct. 14, 2010.