Endocrine System

Your hormones are produced by your endocrine system, a group of ductless glands located around your body. The endocrine system is responsible for monitoring your body’s growth and development, your reproductive system, and for managing homeostasis – in other words, ensuring that your body is kept functioning steadily and evenly.

The glands that make up the endocrine system secrete hormones in response to the levels of chemicals in the body – when they detect a low level of chemicals they stimulate secretion, and when they detect a high level, they inhibit secretion. Glands secrete hormones straight into the blood or into the interstitial fluid, without storing them. The hormones circulate around the body in the bloodstream to the cells within the organs where they are needed – they act as messengers to different cells in your body, to tell the cells to make changes; to grow, for example.

The main glands in the body are:

  • Hypothalamus –just above the brain stem, this gland controls body temperature, hunger and thirst.
  • Pituitary – a pea sized gland at the base of the brain that regulates homeostasis, and stimulates sexual desire.
  • Pineal – a tiny pine cone shaped gland near the centre of the brain which secretes melatonin and influences sleep patterns.
  • Thyroid – one of the largest glands, located in the neck. It controls your metabolism, as well as how sensitive your body is to other hormones.
  • Parathyroids – small glands in the neck, behind the thyroid gland, which maintain your body’s calcium at a constant level.
  • Adrenals – triangular glands above the kidneys which regulate stress response.
  • Islets of Langerhans in the pancreas – produce insulin, glucagons and somatostatin to break down food.
  • Ovaries – egg producing organs in women
  • Testes – sperm producing organs in men