Sweat Glands: The Science Behind Sweat

Perspiration is the body’s way of cooling down, both physically and emotionally. Sweat is healthy and normal in most circumstances, but not always.

To understand the science of sweat, we first need to understand how sweat glands work.

There Are Two Major Types of Sweat Glands

Sweat glands are also called sudoriferous glands. This is from the Latin “sudor” which simply means “sweat”.

Sweat glands are endocrine and exocrine glands. The major glands in the endocrine system are the pituitary, pineal, adrenal, parathyroid and thyroid glands, the pancreas, testes, ovaries, parathyroid gland, and the hypothalamus.

There are more than 2.5 million (up to 4 million on some people) perspiration glands spread out all over the dermis layer of the average person’s skin. A sweat gland consists of a long, coiled tube of cells. The coil is actually sweat ducts connecting the gland to the pore or hair follicle on the skin’s surface. Myoepithelial cells are above the base membrane of blood vessels. They are the cells that contract and excrete the secretions, like in salivary glands. The seromucous glands are in your nose, to keep it moist.

There are also nerve cells from your sympathetic nervous system that connect your nervous system to the sweat glands. That’s why both being nervous, or being hot can make you sweat.

The two major types of sweat glands are eccrine glands and apocrine glands.

Eccrine Glands

The most numerous of the two types are eccrine sweat glands. They are found in virtually all of your skin. They are most dense on your palms, the soles of your feet, and your forehead. There are some, but fewer, on your trunk and on your arms and legs. On the skin surface, each eccrine sweat gland ends in a pore.

The word “eccrine” is from the Greek word “ekkrinein”, which means “secrete”.Sometimes referred to as the merocrine sweat glands, these function to keep us cool. Your eccrine or merocrine glands are in charge of thermo regulation, the hard work of regulating our temperature and kicking into action when we are too hot.

The eccrine sweat glands are activated by the neurotransmitters connected through your nervous system. Your nervous system recognizes when you are too hot, and then uses the neurotransmitters to communicate with your eccrine sweat glands when you need to cool down.

Eccrine sweat has no odor. It is 98-99% water, with some sodium chloride and is used for thermoregulation.

Apocrine Glands

Your apocrines are mostly in your armpits. They are also in your eyelids, groin, and around your nipples. As they reach the surface of your skin, they end up in hair follicles instead of just a pore.

When we say something “smells like sweat”, we are referring to the odor of the apocrine sweat glands. Apocrine secretions are scented, in armpits, groin and around the nipples on the mammary glands. They function to create the odor, but don’t contribute to keeping us cool.

Chemically, the secretions from your apocrine sweat glands are very different than the eccrine sweat glands that secrete mostly water. They secrete steroids, proteins and lipids. The secretions don’t smell as they leave, but when they encounter outside bacteria, the chemicals start to decompose. It is that decomposition that we smell and recognize as “body odor”.

This is what is responsible for causing some people to produce a stronger odor than others. As you would expect, they are located on the palms and soles and your armpits (axillae).

The ceruminous glands are specialized sudoriferous glands that are located subcutaneously in the outer third of your ear canal. This is why some people also have excessive ear wax.

Our bodies are constantly sweating, even when we don’t realize it. You are always working at maintaining a constant temperature, and much of that means staying cool. The amount you sweat depends on the external temperature, but it also depends on your physical activity level. Of course, perspiring can also be a nervous reaction, as it often accompanies anxiety. Your glands function in many positive ways, unless they become overactive to make you sweat excessively.

Why Some People Sweat Excessively

Some people sweat more than other people. Some people perspire excessively. When you sweat too much it is called hyperhidrosis. Some people say they sweat so much, they even sweat while in a swimming pool.

Most of the time, even sweating excessively is harmless. Sometimes, it can be a symptom of an underlying condition that may require medical treatment. Doctors will only diagnose you as having a medical condition if you are perspiring more than would be required to maintain your temperature.

When it is hot outside, everyone will perspire some. It is not a medical problem until the person is dripping wet to the point where the perspiration could actually drip right from the palms of your hands. The profuse wetness can happen without cause; without physical activities, without high external temperatures, a fever and without internal anxiety.

Hormones play a part, too. Puberty, pregnancy and menopause are all prime times for extra sweat. The sweat glands that cause odors during puberty are present in the body from the time of birth. The glands are activated by the puberty hormones, which is why teens are prone to so many unpleasant odors.

Usually, the perspiration that is produced gets carried to the epidermis when one of the triggers for the neurotransmitters signals that there is a reason.

Basal cells make up the innermost layer of the epidermis. They continually divide, so new cells push the older ones towards the skin’s surface, where they are shed.

When the temperature rises, if you have a fever, when you exercise, or when you feel nervous, anxious, or are under stress, your perspiration controls get signalled to go to work. After these issues are no longer a factor, the nerve fibers signal the actions to go on hold.

With hyperhidrosis, between 1% and 2% of the population have glands that never shut off. Even when the situation doesn’t call for cooling down, their bodies don’t get the message to take a rest.

What Is Hyperhidrosis?

Hyperhidrosis is an extreme sweating condition that affects an estimated 4.8% of the worldwide population.

Focal, or primary hyperhidrosis , causes excessive perspiration on the palms of the hands, the underarms, the face, and the feet without any apparent cause.

Generalized, or secondary hyperhidrosis causes excessive perspiration over a larger area, or all over. This can be caused by some medications or by some underlying medical conditions.

Primary Causes

Primary hyperhidrosis is somewhat mysterious. Experts have yet to identify a specific cause or causes. But recent research suggests that genetics might play a role.

Secondary Causes

Unlike primary, secondary hyperhidrosis has many known causes:

• Hyperthyroidism
• Alcohol abuse
• Some medications
• Pregnancy
• Menopause
• Diabetes
• Obesity
• Rheumatoid arthritis
• Parkinson’s disease
• Gout
• Lymphoma
• Infections

Complications – Can Sweat Glands Get Infected?

Hidradenitis Suppurativa is a long-term chronic disease of the apocrine sweat glands. The glands in the groin and underarm areas clog and become infected. The inflammation of the apocrine sweat glands leads to painful lumps of pus. Often, this is a very painful sweat glands disease and causes an unpleasant body odor.

Since the condition is chronic, flare ups happen repeatedly. The flare-ups do not tend to go away over time, so the skin becomes significantly scarred. The flare ups are often as a response to stressful situations.

Some doctors advocate for a long-term treatment using systemic antibiotics such as tetracycline, or erythromycin combined with metronidazole, but generally the disease treatment tends to have poor outcomes.

Treatment Options

Now we know that the apocrine glands contribute to focal (primary) hyperhidrosis so that’s where we need to focus for treatments. Since apocrine glands are not essential to keeping us cool with thermoregulation, they can be targeted for treatment without risking any bodily functions.

Options for the treatment of primary hyperhidrosis include:

• Botox injections for armpits
• Aluminum containing prescription-strength or over-the-counter antiperspirants
• Iontophoresis: Treatment using a low-intensity electric current
• Anticholinergics: A medication that affects nerve signals

Botox

Botox is actually Botulinum toxin. Injecting botulinum toxin A is a treatment option. This is the same medicine that is injected into the face to reduce the appearance of wrinkles.

Botox is specifically FDA approved for the treatment of excessive sweat in the underarms, but it is also used by some doctors on the soles of the feet and palms of the hands.

Botox blocks the neurotransmitters that signal the glands to begin their activation. The treatment may require several Botox injections at once, but results often last for up to a year.

Antiperspirants

Antiperspirants are generally the first step for treatment. Most people already use an antiperspirant daily. Antiperspirants use aluminum salts to block the perspiration when you apply them to your skin.

Antiperspirants are available over-the-counter at supermarkets and drug stores, or there are prescription-strength antiperspirants, too. The over-the-counter products are often less irritating than the prescription-strength antiperspirants. Always begin with over-the-counter brands before asking your doctor about prescriptions.

Often antiperspirants are combined with deodorants. This combination will help to control the odors from your sweat as well as the wetness.

You can apply antiperspirants on any area where you sweat. You can apply them to your hands and feet or even to your hairline.

Applying antiperspirant more frequently will keep your drier. Apply it at bedtime as well as in the morning.

A proprietary formulation such as SweatBlock often manages excessive sweat in almost all cases. If you have not used it yet, do so before moving to the more invasive treatments.

Iontophoresis

A low-level electric current moves through water in a shallow tray. You place your hands and/or feet in the tray for 20 to 30 minutes. The treatment needs to be repeated several times a week, but some people find that after several treatments, they no longer need more.

You can purchase a home-use machine. You may only require a few treatments monthly after the initial period, for maintenance.

Experts tell us Iontophoresis blocks the sweat from the skin’s surface but, no one knows exactly why it works.

Iontophoresis is generally considered safe, but because of the electrical current, it is not recommended for pregnant women, those with pacemakers or metal implants, heart conditions, or epilepsy.

Anticholinergics

Doctor occasionally recommend prescription medicines like anticholinergic drugs after several other treatments have failed. Taken orally, these anticholinergic drugs are able to stop the activation of perspiration.

They do have some side effects for some people, like heart palpitations, blurred vision and urinary issues.

Surgery – Can Sweat Glands be Removed

As a last resort, surgery is considered for severe issues with the hands and underarms. Removing glands entirely or destroying the nerves that send the messages, are both surgical options.

Steps to Take at Home to Control Excessive Perspiration

In addition to any recommendations from your doctor, here are some home remedies to help support your treatments:

• Wear light, breathable clothing.
• Bring along an extra shirt.
• Wear merino wool or polypro socks that wick moisture away from your feet. Bring along a second pair.
• Shower daily using an antibacterial soap. This controls the bacteria that can cause odors.
• Dry yourself off completely afterwards. Then apply antiperspirant.
• Consider using an antibacterial cream.
• Use shoe inserts and underarm liners to absorb the sweat so it won’t ruin your clothes or smell.
• Eliminate spicy foods and alcohol. Both can make you sweat.
• Avoid hot drinks like coffee and tea.

At the risk of sounding brash, we can’t end this article without recommending SweatBlock. Although it may not cure hyperhidrosis or excessive sweating for everyone, it can help most people. It’s certainly worth a try with our “Love it, or it’s free!” guarantee. Try our clinical strength antiperspirant today!