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Hyperhidrosis | Hypohidrosis

Health InformationSweating, perspiration - whatever you want to call - it is important for our health and survival. Just like an air conditioner, your body has a built-in thermostat that helps control your temperature. According to Centers for Disease Control and Prevention (CDC), if your temperature rises above the average, 98.6 degrees, your brain (Read about "The Brain") springs into action alerting the body to start cooling down. A brain signal begins the perspiration process. This cools the body.

Your skin (Read about "Skin") plays a large role in this cooling system; it's responsible for about 90 percent of the body's heat-releasing process. Our bodies expel heat by changing the rate and level of blood circulation as well as releasing water through the skin and sweat glands, according to the National Oceanic and Atmospheric Administration (NOAA).

When overheated, due to exercise or heat exposure, your heart (Read about "The Heart & Cardiovascular System") pumps more blood. Blood vessels in your skin open wide to handle this increased blood flow. The smallest of these blood vessels, the capillaries, thread through upper layers of skin. As blood is circulated closer to the skin's surface, excess heat drains off into the cooler atmosphere. At the same time, water diffuses through the skin from sweat glands, says NOAA. According to the American Academy of Dermatology (AAD), sweating alone doesn't cool the body. The sweat needs to dry on the surface of your skin. Once sweat begins evaporating, your body starts cooling down.

Heat kills by pushing the body beyond its abilities and in a normal year, about 175 Americans succumb to the demands of summer heat. The most vulnerable are the elderly, small children, chronic invalids, those on certain medications - such as tranquilizers and anticholinergics - and persons with weight and alcohol problems. Common heat disorders are sunstroke, heat cramps, heat exhaustion and heatstroke. (Read about "Heat Stroke")

Some facts about sweat

Have you ever asked yourself "What's in sweat anyways?" Well it's much more than meets the eye. It's a mixture of water, sodium, urea, ammonia, amino acids, heavy metals, organic compounds and enzymes, according to AAD.

Why does sweat cause body odor? Although odorless initially, when sweat comes in contact with normal bacteria (Read about "Microorganisms") living on the skin, an odor develops, according to AAD.

Amazingly, under normal circumstances, it only takes a single pea-sized bead of sweat to cool nearly 1 liter (about 1 quart) of blood by 1 degree Fahrenheit, according to the International Hyperhidrosis Society (IHS).

Some people sweat excessively. That is called hyperhidrosis. And there are people who do not sweat on all or parts of their bodies. That is called hypohidrosis or anhidrosis. You can read more about these condition below.

Other reasons for sweating

Indigestion (Read about "Indigestion") is sometimes accompanied by sweating and many women sweat profusely when they experience hot flashes during menopause. (Read about "Menopause") These are fairly common conditions, but sweating can also be a symptom of disease. Sweating is a symptom of both gallstones and hyperthyroidism (Read about "Gallstones" "Thyroid") for example. It can be a symptom of infectious diseases such as tetanus, pneumonia, tuberculosis, or HIV (Read about "Wound Care" "Pneumonia" "Tuberculosis" "HIV / AIDS"), among others.

Sweating can also be a symptom of some cancers including:

There are a number of heart conditions where sweating will occur. They can be very serious and include:

Lastly, some mental health issues manifest themselves, at least partially, via sweating. Anxiety, panic disorder and social phobia (Read about "Anxiety" "Panic Disorder" "Social Phobia") are all conditions that can result in sweating.

If you experience sweating for no apparent reason, or it is accompanied by a fever or chest pain, you should contact your healthcare provider.


Is it possible to sweat too much? Yes. If the body's cooling system is overactive, causing more sweat than necessary, it's a serious medical condition called hyperhidrosis. This extreme sweating can be embarrassing, uncomfortable, anxiety inducing and disabling. Hyperhidrosis can disrupt all aspects of a person's life, from career choices and recreational activities to relationships, emotional well-being and self-image, says AAD. Excessive sweating of the hands is one of the most common types of hyperhidrosis, according to IHS.

If you have hyperhidrosis, you're not alone - it afflicts millions of people around the world (approximately 3 percent of the population). Lack of awareness of this condition leaves more than half of its sufferers undiagnosed or treated for their symptoms, according to IHS.

Treatment for hyperhidrosis

There are several treatment options for hyperhidrosis, according to AAD. They include:

For more information, evaluation and treatment, consult a dermatologist who is the expert on conditions related to skin, hair and nails and can help deal with this irritating, often debilitating condition.

Hypohidrosis | Anhidrosis

The exact opposite of hyperhidrosis is a condition called hypohidrosis or anhidrosis, the inability to sweat. Did you know that being unable to perspire can actually be life threatening? Sweat is the body's coolant and protects you from overheating.

The number of people affected by anhidrosis is unknown because people with mild cases of the condition may not even be aware that they have it and go undiagnosed. Anhidrosis can affect small or large areas of the body and several factors may cause it, says IHS. Anhidrosis of a limited body area is usually not a problem, but anhidrosis over large portions of the body limits your ability to keep cool. If you suspect you have anhidrosis, do all that you can to prevent heat exhaustion, heat stroke, and dehydration (Read about "Dehydration") until you can speak with your healthcare provider, says IHS. Factors leading to anhidrosis may include antipsychotic medications used to treat serious mental disorders, drugs with anticholinergic properties and calcium-channel blockers, according to AAD. Nerve and skin damage, as well as genetics (Read about "Genetics"), can also result in anhidrosis.

Treatment for anhidrosis

According to IHS, treatment for anhidrosis depends on the cause and unfortunately, many cases will not be easily treated. Factors such as nerve damage, skin injuries, dehydration or clogged ducts all could be to blame. If you develop a noticeable decrease in sweating, it's important to talk to a healthcare professional.

Healthy sweating

Keeping hydrated is essential to healthy sweating. CDC says the following tips can help you stay hydrated:

NOAA says to stay hydrated:

All Concept Communications material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.

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By printing and/or reading this article, you agree that you accept all terms and conditions of use, as specified online.