Glands are important organs located throughout the body. They produce and release substances that perform certain functions. Though you have many glands throughout your body, they fall into two types: endocrine and exocrine.
Endocrine and exocrine glands serve very different purposes in the body.
Endocrine glands are part of your endocrine system. They make hormones and release them into your bloodstream. These hormones control a number of important functions in your body, such as:
- your growth and development
Your endocrine glands include:
There are also organs that contain endocrine tissue and act as glands. These include the:
Your exocrine glands produce other substances — not hormones — that are released through ducts to the exterior of your body, such as sweat, saliva, and tears.
The substances released by your exocrine glands play important roles in your body. They do things like help regulate your body temperature, protect your skin and eyes, and even help mothers feed babies by producing breast milk.
Your exocrine glands include:
Lymph nodes are often referred to as glands, but they’re not true glands. They’re part of your immune system and help your body fight infection.
You have glands throughout your body, all varying in size and function. Here are a few examples of these glands and what they do.
Your thyroid gland is located in the front of your neck, just below your larynx. It measures approximately two inches and has a shape similar to a butterfly. It secretes hormones that affect virtually every tissue in your body. Thyroid hormones regulate your metabolism, heart, and digestive function. They also play a role in your brain and nerve development, muscle control, and mood.
Your thyroid function is controlled by your pituitary, which is a small gland at the base of your brain.
The pituitary gland is a pea-sized gland at the base of your brain, just behind the bridge of your nose. It’s controlled by the hypothalamus, which sits just above it. The pituitary gland is often called the master gland because it controls a number of other hormone glands, including the:
- adrenal gland
The hypothalamus functions as a communication center for your pituitary gland, sending signals and messages to the pituitary to produce and release hormones that trigger the production and release of other hormones.
Your hypothalamus influences a number of your body’s functions, including:
- temperature regulation
- food intake
- sleep and wakefulness
- emotional behavior
Your pineal gland is located deep in the center of your brain. Its function is not completely understood, but we do know that it secretes and regulates certain hormones, including melatonin. Melatonin helps regulate your sleep patterns, which are also known as circadian rhythms.
The pineal gland also plays a role in the regulation of female hormones, which affect the menstrual cycle and fertility.
Your adrenal glands are located at the top of each kidney. They produce various hormones, some of which include:
- a small amount of sex hormones called androgens
The hormones produced by your adrenal glands have several important functions. They help your body:
- control blood sugar
- burn fat and protein
- regulate blood pressure
- react to stressors
The pancreas — a long, flat organ located in your abdomen — is made up of two types of glands: exocrine and endocrine. The pancreas is surrounded by the small intestine, stomach, liver, gallbladder, and spleen.
The pancreas plays an important role in converting the food you eat into fuel for your body’s cells. It does this by producing digestive enzymes that are released into your small bowel to break down and digest food. It also makes hormones that control your blood glucose levels.
Your skin is covered in sweat glands of which there are two types: eccrine and apocrine. Your eccrine glands open directly onto your skin and regulate your body temperature by releasing water to the surface of your skin when your body temperature rises.
Apocrine glands open into the hair follicle and are found in hair-bearing areas, such as the skin, armpits, and groin. These glands secrete a milky fluid, usually as a response to stress. Your body also contains modified apocrine glands:
- on the eyelids
- on the areola and nipples
- in the nose
- in the ears
Sebaceous glands are located throughout your skin, though there are few on your hands and feet and none on your palms and soles. They secrete an oily substance called sebum that lubricates your skin.
Most of these glands release onto a hair follicle, though a few open directly onto the skin’s surface, such as Meibomian glands on the eyelids, Fordyce spots on the genitals an upper lip, and Tyson glands on the foreskin.
These glands perform a few functions in your body, such as:
- regulating your body temperature by working with your sweat glands
- helping your skin retain moisture
- helping fight infection caused by bacteria and fungi
Your salivary glands are located in your mouth. You have hundreds of small glands located throughout your:
You have three pairs of major salivary glands, including the:
- parotid glands, located in front of and just below your ears
- sublingual glands, located just under your tongue
- submandibular glands, located below your jaw
Salivary glands produce saliva and empty into your mouth through ducts. Saliva serves a few important purposes, including moistening your food to help you chew, swallow, and digest it. Saliva also contains antibodies that kill germs to keep your mouth healthy.
Mammary glands, which are a type of sweat gland, are responsible for the production of breastmilk. Males also have glandular tissue in the breasts, but estrogen produced during puberty triggers the growth of this tissue in females.
Hormonal changes during pregnancy signal the ducts to produce milk in preparation for the baby.
There are a number of different problems that can affect the glands. Depending on the glands affected, a person could experience symptoms that affect different parts of the body.
Hypothyroidism and hyperthyroidism are common thyroid disorders. Hypothyroidism occurs because of an underactive thyroid that doesn’t produce enough thyroid hormones. Hyperthyroidism is the result of an overactive thyroid that produces too much thyroid hormone. Both conditions can cause an enlarged thyroid gland, or goiter.
Hypothyroidism can also cause unintentional weight gain, fatigue, and a slow heart rate, while hyperthyroidism does the opposite, causing unintended weight loss, nervousness, and a rapid heart rate. Both conditions can usually be treated with medication to restore proper thyroid function.
A healthy pancreas releases insulin when blood sugar gets too high. Insulin causes your cells to convert sugar to use as energy or to store it as fat. In diabetes, your pancreas either doesn’t produce insulin or doesn’t use it properly, leading to high blood sugar.
Diabetes can lead to a number of serious complications, including nerve damage, heart disease, and stroke. There are two different types of diabetes. Common symptoms include increased thirst, changes in weight, and frequent or recurring infections.
Treatment depends on the type of diabetes, but may consist of medication, insulin, and lifestyle changes.
Adrenal gland disorders
Adrenal gland disorders are caused by too much or too little of a certain hormone, such as cortisol. Cushing syndrome, an adrenal disorder caused by high cortisol, causes weight gain, a fatty hump between the shoulders, and high blood pressure. It’s often caused by prolonged use of corticosteroids.
Adrenal insufficiency, which happens when your body produces too little cortisol, and sometimes aldosterone, can cause decreased appetite, weight loss, and muscle weakness. Adrenal disorders can be treated using medication, surgery, and other therapies, or by stopping corticosteroids.
Salivary gland disorders
The formation of stones or tumors, infections, and certain medical conditions, such as autoimmune disorders and HIV and AIDs, can prevent the salivary glands from functioning properly. When your salivary glands don’t produce enough saliva, it can affect chewing, swallowing, and taste. It can also increase your risk of oral infections, such as cavities.
Symptoms often include pain or swelling in your face, neck, or under your tongue, and dry mouth. Treatment of salivary gland disorders depends on the cause and may include medication or surgery.
Problems with your glands can cause vague symptoms. See your doctor if you notice any unusual swelling or changes in your appearance, such as unexplained weight changes. Also see your doctor if you develop changes in your heart rate or palpitations.
Fatigue, weakness, and changes in your appetite lasting over two weeks should also prompt a visit to the doctor.
Your glands play a role in almost every bodily function. Endocrine glands secrete hormones to your bloodstream. Exocrine glands secrete other substances to your body’s exterior.
A problem with one of your glands needs to be treated to prevent serious complications. See your doctor if you suspect you have a gland disorder.