Region · Volume I
The Pituitary Gland
The pea-sized master gland taking orders from above.
Hanging just beneath the hypothalamus on a thin stalk, the pituitary gland is the size of a pea — and it releases the hormones that control growth, stress, metabolism, and reproduction throughout your entire body.
What it does
- Releasing growth hormone
- Triggering the thyroid and adrenal glands
- Managing water balance in the body
- Controlling reproductive hormones
In the real world
Why does this matter?
01
Growth in adolescence
Growth-hormone pulses from the pituitary during sleep are why teenagers can grow inches in a summer — and why sleep loss during puberty matters.
02
Treating pituitary tumors
Most pituitary tumors are benign but disrupt hormones. Surgeons can now remove many of them through the nose, with no visible incision.
03
Endocrine medicine
Synthetic pituitary hormones treat thyroid disease, infertility, and growth disorders — an entire branch of medicine built on one small gland.