An endocrinologist is a doctor who diagnoses and treats hormone-related problems and complications, such as an overactive thyroid, diabetes, and fertility issues.

Endocrinology and endocrinologists focus on the hormones, the many glands and tissues that produce them, and how to redress the balance when things go wrong.

Hormones regulate metabolism, respiration, growth, reproduction, sensory perception, and movement. Hormone imbalances can lead to a wide range of medical conditions.

Humans have over 50 different hormones. They can exist in tiny amounts but still significantly affect bodily function and development.

Here, find out why a person might need to see an endocrinologist and some diseases they can help with. Then, read about the different parts of the endocrine system, the hormones they produce, and some health conditions that can arise if they do not function effectively.

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If a person sees a physician about symptoms of a health problem, the physician may refer them to an endocrinologist. They will do this if they believe the underlying cause may be hormone related.

Endocrinologists are doctors trained to diagnose and manage diseases that affect the glands and hormones. They aim to restore hormonal balance within the body’s systems.

There are three broad groups of endocrine disorders:

  • Hyposecretion: A gland does not produce enough hormones.
  • Hypersecretion: A gland produces too much of its hormones.
  • Tumors: These may be malignant (cancerous) or benign (noncancerous).

A hormonal imbalance can result from genetic or environmental factors.

A person may be born with a genetic feature that affects hormone production, or they may acquire a disease, such as type 2 diabetes, that changes hormone activity in the body.

Environmental factors that can affect hormone function include the use of endocrine-disrupting chemicals. These are present in the air, soil, water supply, and manufactured products.

Sometimes, both environmental and genetic features play a role.

Here are just a few of the conditions endocrinologists often treat:

A note about sex and gender

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

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The endocrine system consists of a number of glands. The hormones they release affect many different functions. When the hormones leave the glands, they enter the bloodstream, where they travel to organs and tissues throughout the body.

Hormones regulate a wide range of functions, such as:

  • breathing
  • metabolism, which is how the body converts food into energy
  • touch, feel, and other senses
  • movement
  • sexual development, reproduction, and fertility
  • growth

The endocrine system consists of many glands that produce and regulate hormones. The body needs an appropriate balance of these hormones to work effectively.

Adrenal glands

The adrenal glands are located above the kidneys. They are divided into two regions. The right gland is triangular, and the left is crescent-shaped.

The adrenal glands secrete:

Both males and females have some androgen, but males have higher levels. Androgens play a key role in the development of characteristics associated with males, such as facial hair and a deeper voice.

Health issues

Hypersecretion, or high levels of adrenal hormones, may lead to:

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Hyposecretion, or low levels, may lead to:


The hypothalamus is located just above the brain stem and below the thalamus.

This gland activates and controls involuntary body functions, including:

  • appetite
  • fluid balance in the body
  • body temperature
  • the circadian cycle or body clock
  • milk production
  • growth

The hypothalamus links the nervous system to the endocrine system via the attached pituitary gland.

The hormones it manages affect the activity of the:

  • thyroid gland
  • adrenal glands
  • reproductive organs

Which nutrients support the hypothalamus and pituitary gland?

Ovaries and testicles

The ovaries are located on either side of the uterus in females. They are the female gonads and secrete estrogen, progesterone, testosterone, and other hormones.

The ovaries are part of the female reproductive system and essential for:

The testicles or testes are the male gonads. They are located in the scrotum, below the penis. They secrete androgens, mainly testosterone. They are part of the male reproductive system.

Androgens are essential for:

  • sexual development
  • puberty
  • facial hair
  • sexual behavior
  • libido
  • erectile function
  • fertility and conception
  • the formation of sperm cells

Both males and females produce estrogen and testosterone, but the levels and balance are different. For this reason, people consider estrogen a female hormone and testosterone a male hormone.

What is the difference between sex and gender?


Located in the abdomen, the pancreas is both an endocrine gland and a digestive organ.

It releases:

  • Insulin: Insulin is essential for carbohydrate and fat metabolism in the body.
  • Somatostatin: This hormone regulates endocrine and nervous system functions. It also controls the secretion of several hormones, such as gastrin, insulin, and growth hormone.
  • Glucagon: This peptide hormone raises blood glucose levels when they fall too low.
  • Pancreatic polypeptide: This helps control the secretion of substances made by the pancreas.

How do insulin and glucagon regulate blood sugar?

Health issues

Diabetes and digestive issues can result from problems with the pancreas. The main concerns relate to blood sugar imbalance.

If the pancreas produces too much insulin, hypoglycemia will result. This is when blood glucose levels are too low. If it produces too little, a person will have hyperglycemia, or high blood glucose levels.

Diabetes happens when the pancreas can no longer produce or use insulin effectively, also known as insulin resistance. A wide range of complications can result.

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Parathyroid glands

These are small endocrine glands in the neck. They produce parathyroid hormone, which regulates calcium and phosphate in the blood.

Health issues

Muscles and nerves can only operate effectively if these chemicals are at the correct levels.

High levels of parathyroid hormone may lead to brittle bones that fracture easily and stones in the urinary system.

Low levels may lead to involuntary muscle contractions caused by low calcium levels in plasma.

Pineal body, or pineal gland

The pineal gland is a small endocrine gland located deep in the brain. It secretes melatonin and helps control the body’s sleep and wakefulness patterns.

Changes that can disrupt the function of this gland include:

  • tumors
  • cysts
  • calcifications
  • changes to light-dark or sleep-wake patterns, for instance, due to jet lag

Pituitary gland

This is an endocrine gland attached to the hypothalamus, at the base of the brain.

It is sometimes called the main endocrine master gland because it secretes hormones that regulate the functions of other glands, as well as growth and several other bodily functions.

The anterior, or front, pituitary secretes hormones that affect:

  • reproduction
  • growth
  • metabolism
  • response to stress or trauma
  • thyroid function
  • adrenocortical function

The posterior, or rear, pituitary secretes oxytocin, a hormone that increases contractions of the uterus. It also secretes an antidiuretic hormone (ADH) that encourages the kidneys to reabsorb water.

Health issues

Depending on the hormone produced, an overactive pituitary gland may lead to gigantism, or excessive growth. Underactivity may lead to limited growth, short stature, and low activity in other endocrine glands.

If the gland produces too much ADH, fluid retention can occur. Too little can lead to excess water in the urine.

Thymus gland

The thymus gland is located beneath the breastbone, or sternum. It is the main organ responsible for the production and maturing of immune cells or lymphocytes, which protect the body from infections and other diseases.

Problems with this gland can seriously affect a person’s health.

Health issues

Hypersecretion may cause the immune system to overreact to perceived threats. This may result in an autoimmune disease.

Hyposecretion may lead to a weakened immune system, where the body is unable to fight infection and easily succumbs to viruses, bacteria, and other pathogens.

Thyroid gland

The thyroid gland is a butterfly-shaped gland located just below the Adam’s apple in the neck.

The hormones it produces are crucial for regulating:

The thyroid gland produces two types of hormones. The inactive thyroid hormone thyroxine (T4) makes up 90% of hormones produced while the active thyroid hormone, triiodothyronine (T3) makes up 10%.

Thyroxine is converted either to active thyroid hormone or another inactive hormone for various purposes throughout the body.

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Health issues

Hyperthyroidism, or an overactive thyroid, often stems from Graves’ disease.

It can lead to:

  • accelerated metabolism
  • sweating
  • arrhythmia or irregular heartbeat
  • weight loss
  • nervousness

Hypothyroidism may lead to:

During the first visit, the doctor will ask a series of questions to help reach a diagnosis.

These might cover:

  • current medications
  • family history of hormonal problems
  • other medical conditions, including allergies
  • dietary and lifestyle habits

It can help to list any existing symptoms before the visit.

The endocrinologist might ask about symptoms that do not seem to be related. This is because small changes in one gland can affect the whole body.

The endocrinologist may check the person’s

  • heart rate
  • blood pressure
  • skin, hair, teeth, and mouth

They may take blood and urine samples for testing.

Following a diagnosis, the endocrinologist will suggest a treatment plan. This will depend on which underlying condition is causing the symptoms.

Hormones affect functions throughout the body. An imbalance can cause a wide range of health issues.

A family doctor may refer a person to an endocrinologist if they believe a hormone problem is the underlying cause of a health problem.

If you need to find an endocrinologist, ask a doctor or see the American Association of Clinical Endocrinologists’ list of qualified practitioners. Check with your insurer regarding cover.

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