Cortisol: What It Is, Function, Symptoms & Levels

What is Cortisol?

• Cortisol is a hormone released by the adrenal glands.
• It is a glucocorticoid, a type of steroid hormone.
• Known as a stress hormone but essential for various bodily functions:
  • Regulates glucose (sugar) usage for energy.
  • Decreases inflammation.
  • Regulates blood pressure.
  • Helps control sleep-wake cycle.
• The body monitors cortisol levels for homeostasis.

Is Cortisol a Stress Hormone?

• Plays a key role in managing stress:
  • Acute stress.
  • Chronic stress.
  • Traumatic stress.
• Also involved in several other bodily functions.

Effects of Cortisol on the Body

Regulating Stress Response

• Released during stress after adrenaline to keep the body alert.
• Triggers glucose release from the liver for quick energy.

Regulating Metabolism and Blood Sugar Levels

• Influences metabolic processes:
  • Affects how the body uses glucose.
  • Decreases insulin and increases glucagon release from the pancreas.
  • Manages glucose use in other bodily tissues.

Suppressing Inflammation

• Boosts immunity by limiting inflammation in short spurts.
• Consistently high levels can lead to chronic inflammation and weakened immune system.

Regulating Blood Pressure

• Exact mechanism unclear:
  • High cortisol can cause high blood pressure.
  • Low cortisol can cause low blood pressure.

Controlling Sleep-Wake Cycle

• Lower levels in the evening and peak in the morning.
• Important for circadian rhythm and waking up.

Control of Cortisol Levels

• Regulated by the hypothalamus and pituitary gland:
  1. Hypothalamus releases corticotropin-releasing hormone (CRH) when cortisol is low.
  2. CRH directs pituitary gland to produce adrenocorticotropic hormone (ACTH).
  3. ACTH triggers adrenal glands to release cortisol.
• Proper function of hypothalamus, pituitary gland, and adrenal glands is essential.

Causes of High Cortisol Levels (Hypercortisolism)

• Often related to Cushing syndrome:
  • High doses of corticosteroid medications.
  • Tumors producing ACTH, often in the pituitary gland.
  • Adrenal gland tumors causing excess cortisol.

Symptoms of High Cortisol Levels

• Weight gain, especially in face and belly.
• Fatty deposits between shoulder blades.
• Purple stretch marks on belly.
• Muscle weakness in upper arms and thighs.
• High blood sugar, potential development of Type 2 diabetes.
• High blood pressure.
• Excessive hair growth in females.
• Weak bones and fractures.

Causes of Low Cortisol Levels (Hypocortisolism)

• Known as adrenal insufficiency, primary or secondary:
  • Primary often due to immune system attacking adrenal glands (Addison’s disease).
  • Secondary due to underactive pituitary gland or pituitary tumor.
  • Sudden stop of corticosteroid treatment can also lead to low cortisol.

Symptoms of Low Cortisol Levels

• Symptoms related to adrenal insufficiency.

When to See a Healthcare Provider

• Consult if experiencing symptoms of Cushing syndrome or adrenal insufficiency.
• Discuss with a provider if concerned about managing stress.