Sweating is the release of a salty liquid from the body's sweat glands. This process is also called perspiration.

Sweating is an essential function that helps the body stay cool. Sweat is commonly found under the arms, on the feet, and on the palms of the hands.

How much you sweat depends on how many sweat glands you have. A person is born with about two to four million sweat glands. The glands start to become fully active during puberty. Women actually have more sweat glands then men -- men's glands are just more active.

Because sweating is the body's natural way of regulating temperature, people sweat more when it's hot outside. People also sweat more when they exercise, or in response to situations that make them nervous, angry, embarrassed, or afraid.

If sweating is accompanied by fever, weight loss, chest pain, shortness of breath, or a rapid, pounding heartbeat, talk to a doctor. These symptoms may indicate an underlying problem, such as hyperthyroidism. Excessive sweating may also be a symptom of menopause.

See also:

• Sweating - absent
• Sweating - excessive

• Alcohol
• Caffeine
• Cancer
• Certain medicines, including thyroid hormone, morphine, drugs to reduce fevers, and medicines to treat mental disorders
• Emotional or stressful situations (anxiety)
• Exercise
• Fever
• Infection
• Low blood sugar
• Menopause
• Overactive thyroid gland
• Spicy foods (known as "gustatory sweating")
• Warm temperatures
• Withdrawal from alcohol or narcotic pain killers

After sweating, you should:

• Wash the face and body
• Change clothes and bed sheets
• Drink plenty of water to replace lost body fluids
• Slightly lower room temperature to prevent more sweating

• You sweat a lot or if sweating lasts for a long time or can't be explained.
• Sweating occurs with or is followed by chest pain or pressure.
• Sweating is accompanied by weight loss or most often occurs during sleep.

Goldman L, Ausiello D. Cecil Textbook of Medicine, 22nd ed. Philadelphia, Pa: WB Saunders; 2004:2365, 2446-2447.

Grant RA. Don't Sweat It. Dermatology Insights. 2002; 3 (1):12-13.

Paradox P, Frey R. Body Odor. In: Longe J, ed. Gale Encyclopedia of Alternative Medicine. Vol. 1. 2nd ed. Detroit, Mi: Gale; 2005:269-271.

Rosenthal MS. Temperature Regulation. In: Robinson R, ed. Biology. Vol. 4. New York, NY: Macmillan Reference USA; 2002:154-157.