- The adrenal cortex—the outer part of the gland—produces hormones that are vital to life, such as cortisol (which helps regulate metabolism and helps your body respond to stress) and aldosterone (which helps control blood pressure).
- The adrenal medulla—the inner part of the gland—produces nonessential (that is, you don’t need them to live) hormones, such as adrenaline (which helps your body react to stress).
The adrenal glands are arguably best known for secreting the hormone adrenaline, which rapidly prepares your body to spring into action in a stressful situation, called “fight-or-flight response”—a process initiated by the sympathetic nervous system when your body encounters a threatening (stressful) situation. The two hormones released are:
- Epinephrine: Most people know epinephrine by its other name—adrenaline. This hormone rapidly responds to stress by increasing your heart rate and rushing blood to the muscles and brain. It also spikes your blood sugar level by helping convert glycogen to glucose in the liver. (Glycogen is the liver’s storage form of glucose.)
- Norepinephrine: Also known as noradrenaline, this hormone works with epinephrine in responding to stress. However, it can cause vasoconstriction (the narrowing of blood vessels). This results in high blood pressure.
- The principal mineralocorticoid is aldosterone, which maintains the right balance of salt and water while helping control blood pressure.
- Hydrocortisone: Commonly known as cortisol, it regulates how the body converts fats, proteins, and carbohydrates to energy. It also helps regulate blood pressure and cardiovascular function.
- Corticosterone: This hormone works with hydrocortisone to regulate immune response and suppress inflammatory reactions.
Last are the SEX hormones. The adrenal cortex releases small amounts of male and female sex hormones. However, their impact is usually overshadowed by the greater amounts of hormones (such as estrogen and testosterone) released by the ovaries or testes.
- Addison’s disease: This rare disorder may affect anyone at any age. It develops when the adrenal cortex fails to produce enough cortisol and aldosterone. To learn more, read our article about Addison’s Disease.
- Adrenal cancer: Adrenal cancer is an aggressive cancer, but it’s very rare. Malignant adrenal tumors are rarely confined to the adrenal glands—they tend to spread to other organs and cause adverse changes within the body because of the excess hormones they produce. To learn more, read our article about adrenal cancer.
- Cushing’s syndrome: Cushing’s syndrome is an uncommon condition that is essentially the opposite of Addison’s disease. It is caused by overproduction of the hormone cortisol. There are a variety of causes of this disorder—a tumor in the adrenal gland or pituitary gland could be to blame. To learn more, read our article about Cushing’s syndrome.
- Congenital adrenal hyperplasia: This genetic disorder is characterized by low levels of cortisol. It’s common for people with congenital adrenal hyperplasia to have additional hormone problems such as low levels of aldosterone (which maintains a balance of water and salt).