The Endocrine System
Think of the endocrine system as the body's communications network, where glands house hormones that act as chemical messengers and transmit information to cells throughout the body. These hormones influence almost every single body cell and organ and are responsible for growth, metabolism, and sexual development and function. Once released by specific glands, hormones travel through the bloodstream to the targeted organ, where they incite the organ to action.
In addition to the thyroid, the endocrine system includes the:
Adrenal glands: These are located above the kidney, and affect metabolism, the body's stress response, and salt regulation.
Hypothalamus: This part of the brain regulates the pituitary gland as well as involuntary body functions, sleep, appetite, and hormones.
Ovaries and testicles: These are the sex organs, which produce hormones involved in influencing female and male sexual characteristics. They regulate the menstrual cycle in women and sperm production in men.
Pancreas: This is located below your stomach, and secretes insulin, a hormone that regulates the body's use of glucose.
Parathyroid glands: These are located near the thyroid, and regulate calcium levels in the blood.
Pineal gland: This is in the back of the brain, and produces melatonin, a hormone involved in sleep-wake cycles.
Pituitary gland: This is located near the base of the brain, and produces numerous hormones that affect the other endocrine glands, including the thyroid.
Thymus gland: This is located at the top of the chest, and is involved in the body's immune function.
Each one of these glands plays a vital role in keeping you healthy, but none of them exists in isolation. A problem in any of these glands can produce effects elsewhere in the endocrine system, including in the thyroid gland. The pituitary gland and the adrenal glands, in particular, have a direct connection to the thyroid.