Eccrine Glands

What are eccrine glands?

Eccrine glands, also called eccrine sweat glands, are tiny structures that produce and secrete sweat. They’re located within the layers of your skin. You have millions of eccrine glands spread across your body, from your face to your feet.

Eccrine glands are working even when you don’t notice you’re sweating. But when you’re exerting yourself or in a warm environment, your eccrine glands work extra hard to produce more sweat. That’s because eccrine glands are your body’s natural air conditioning system. They make sweat to lower your body temperature and keep you from overheating.

Most of your sweat glands are eccrine. You have another type of sweat gland, called an apocrine gland, that makes sweat, too. But eccrine glands do most of the heavy lifting when it comes to cooling you down. Both eccrine and apocrine sweat glands are part of your exocrine system. They’re examples of exocrine glands. These are glands that release substances through ducts onto bodily surfaces.

Eccrine vs. apocrine sweat glands — what’s the difference? 

The chart below lists some key differences between eccrine and apocrine sweat glands.

What is the main function of eccrine glands?

The main function of your eccrine glands is to cool your body when you get too hot. They produce what we might call “common sweat.” This is the clear, light sweat that comes out when your body temperature goes up. It’s made up mostly of water and electrolytes. Eccrine glands produce sweat in response to things like physical activity, hot weather and a fever.

Your body has a careful system in place to manage your internal temperature (thermoregulation). A specific part of your hypothalamus recognizes when your body is warmer than normal. It sends out chemical messengers (neurotransmitters) that let your eccrine glands know it’s time to ramp up sweat production.

In response, eccrine glands all over your body make sweat and send it to your skin’s surface. From there, the sweat evaporates (turns from liquid form into gas form). This process cools your body and helps you return to a normal temperature. Your eccrine glands can churn out up to 4 liters of sweat in one hour to get your temperature where it needs to be.

Your body relies on your eccrine glands to work properly so you don’t overheat. When your body temperature is too high, you run the risk of serious complications, like heat exhaustion and heatstroke.

How many eccrine sweat glands do you have?

You have anywhere from 2 million to 4 million eccrine sweat glands. The exact number can vary widely from person to person.

Where are eccrine glands located?

Eccrine glands are located in your skin, and are spread out all across your body. Some eccrine glands are in dense clusters, while others are farther apart. They’re most tightly packed together on the palms of your hands and the soles of your feet. In these areas, you have anywhere from 250 to 500 glands per square centimeter (smaller than a postage stamp).

What are the parts of an eccrine sweat gland?

Each eccrine gland has two main parts:

• A secretory coil (tubule) that makes sweat: This resides in the lower part of the middle layer of your skin (dermis).
• A duct that sends sweat up to your skin’s surface: The duct also reabsorbs some salt (sodium and chloride) from your sweat to prevent you from losing too much in your sweat.

Some scientists further divide the duct into three distinct subunits:

• A coiled part that travels upward from the secretory tubule through your dermis
• A straight part that keeps traveling up through your dermis
• A coiled part (acrosyringium) that travels through the top layer of your skin (epidermis) until it reaches the surface

When do eccrine glands become active?

Eccrine glands become active, or start producing sweat, right after you’re born. This makes eccrine glands different from apocrine glands, which don’t start making sweat until puberty.

What common conditions affect eccrine glands?

Conditions that can affect your eccrine sweat glands include:

• Anhidrosis: Some of your eccrine glands don’t produce sweat as they should. This puts you at risk of overheating and related complications.
• Hyperhidrosis: You sweat more than needed to cool your body. The extra sweat soaks your clothes and may get in the way of your daily life. This condition can occur due to a genetic change, as a complication of another medical condition or as a side effect of medication.
• Heat rash: A clog in your sweat gland ducts causes an itchy rash. This is uncomfortable but usually goes away with at-home care.

When should I contact a healthcare provider?

Contact a provider if:

• Sweating negatively impacts your life.
• You feel you don’t sweat much or at all when expected (like when you’re working out or in a warm environment).
• You have severe heat rash that isn’t going away with at-home treatment.