The cortisol hormone is a stress hormone that plays a vital role in helping the body cope with stress and maintain the balance of various systems (Homeostasis). It is produced by the adrenal gland under the control of the following system:
- The Hypothalamus secretes Corticotropin-Releasing Hormone (CRH).
- The Hypothalamus secretes Corticotropin-Releasing Hormone (CRH).
- The Hypothalamus secretes Corticotropin-Releasing Hormone (CRH).
How Cortisol Works?
The function of the cortisol hormone is regulated through the hypothalamus, which secretes CRH (Corticotropin-Releasing Hormone). This stimulates the pituitary gland to secrete ACTH (Adrenocorticotropic Hormone), which in turn stimulates the adrenal gland to secrete the cortisol hormone. This system is called the HPA axis (Hypothalamic-Pituitary-Adrenal axis).
The HPA axis is the body’s stress control axis that connects the functions between the brain and the hormonal system to maintain the body’s balance (Homeostasis). It has 3 main components:
- The Hypothalamus secretes CRH (the initial signal of stress), and CRH functions to:
- Act as an on-off switch for the body’s stress response.
- Prepare the body, such as increasing energy, increasing alertness, and adjusting immune function.
- Excessive CRH secretion affects: Poor sleep quality, Visceral fat accumulation, Chronic inflammation (Inflammaging), Cognitive decline (Brain fatigue).
- Excessive CRH secretion affects: Poor sleep quality, Visceral fat accumulation, Chronic inflammation (Inflammaging), Cognitive decline (Brain fatigue).
- Crucial roles of ACTH: Regulates the secretion of Cortisol (stress hormone). Helps the body respond to stress, affecting energy, immunity, inflammation, and bodily balance (Homeostasis).
- If ACTH levels are abnormal: Too high: May be found in chronic stress conditions or certain diseases like Cushing’s disease. Too low: May cause low cortisol hormone levels, leading to fatigue and low blood pressure due to adrenal insufficiency.
- The Adrenal gland secretes the stress hormone (Cortisol). Afterward, Cortisol provides feedback to inhibit the system to prevent hormone levels from getting too high.
Stress Hormone (Cortisol Hormone):
- Increases in the morning: To awaken the body according to the biological clock (Circadian rhythm), increase glucose availability, and prepare the brain for thinking and working.
Decreases during the day: It gradually declines.
- Lowest at night: To allow the body to rest and prepare for sleep.
How important is the role of the HPA axis to health?
The HPA axis is crucial and affects many systems in the body, such as:
- Brain and mood.
- Sleep (Circadian Rhythm).
- Metabolic system.
- Immune system and inflammation.
- Energy and stress tolerance (Resilience).
How does an unbalanced HPA axis (HPA dysregulation) affect the body?
It is often caused by Chronic Stress and will impact:
- Abnormally high or low cortisol levels.
- Insomnia.
- Chronic fatigue.
- Visceral fat.
- Insulin Resistance.
- Brain fatigue and memory decline.
Summary: The HPA axis is a stress control system that creates balance in life and the body.
- If functioning well: The body has good resilience, good sleep, and good energy.
- If dysregulated: It will accelerate aging and increase the risk of Non-Communicable Diseases (NCDs).
Crucial roles of Cortisol Hormone
Cortisol is the primary hormone in helping the body “cope with stress” and maintain the balance of various systems as follows:
- Regulates stress response: When the body is stressed (physically and mentally), cortisol levels increase to help the body enter a Fight or Flight state and increase energy to prepare for emergency situations. If cortisol is chronically high, it leads to chronic stress, negatively affecting many systems in the body.
- Regulates blood sugar and energy (Metabolism): To ensure the body has “ready-to-use energy” at all times by: Stimulating new glucose production (Gluconeogenesis) in the liver. Increasing blood sugar levels. Stimulating muscle breakdown and fat breakdown.
- Regulates blood sugar and energy (Metabolism): To ensure the body has “ready-to-use energy” at all times by: Stimulating new glucose production (Gluconeogenesis) in the liver. Increasing blood sugar levels. Stimulating muscle breakdown and fat breakdown.
- Regulates the cardiovascular system: If cortisol is chronically high, there is a risk of hypertension and cardiovascular disease (CVD). Cortisol helps to: Control blood pressure. Increase blood vessel response to Adrenaline. Affect vascular tone.
- Effects on Brain & Mood: Cortisol affects: The part of the brain related to memory and learning (Hippocampus (Memory center)). Mood, memory, and sleep. When cortisol is chronically high, it affects: Memory decline. Depression and Anxiety. Sleep disruption (not sleeping deeply).
- Effects on Brain & Mood: Cortisol affects: The part of the brain related to memory and learning (Hippocampus (Memory center)). Mood, memory, and sleep. When cortisol is chronically high, it affects: Memory decline. Depression and Anxiety. Sleep disruption (not sleeping deeply).
Regulates the biological clock (Circadian rhythm): Cortisol function has a clear pattern, such as: High in the morning: Helps you wake up and feel refreshed. Low at night: Helps you sleep. If the body’s rhythm is abnormal, it will result in: Fatigue. Insomnia. Hormonal imbalance in the body.
How do high Cortisol levels affect the “Cellular level”?
- Metabolism and Energy: Stimulates gluconeogenesis, which increases blood sugar. Causes muscle breakdown (Catabolism). Increases fat accumulation, especially Visceral fat. If chronically high, there is a risk of insulin resistance and metabolic syndrome.
- DNA and Cellular Aging: Increases oxidative stress (ROS) beyond balance. Interferes with DNA repair. Accelerates cellular aging and telomere shortening. Linked to the body’s aging process and longevity decline.
- Brain and Cognitive function: Affects the Hippocampus (Memory center). Cognitive function is the brain’s ability regarding memory, analytical thinking, learning, concentration, and decision-making, etc. Chronically high cortisol affects: Memory decline. Poor concentration. Risk of cognitive decline.
- Immune system: Suppresses immunity (Anti-inflammatory effect in the short term). But if chronically high, it leads to immune dysfunction and increases chronic inflammation (Paradoxical effect), leading to aging-related chronic inflammation (Inflammaging).
- * Muscle & Bone: Causes muscle breakdown (Catabolism). Reduces bone formation, affecting osteoblast activity. Increases bone resorption. Risk of osteoporosis.
- Cardiovascular system: High blood pressure. Causes endothelial dysfunction. Increases the risk of atherosclerosis (hardening and narrowing of arteries).
- Hormonal balance: Suppresses sex hormones (Estrogen / Testosterone / DHEA). Interferes with thyroid function (reduced T4 -> T3 conversion), causing fatigue, weight gain, and hormonal imbalance.
Which organs are affected by high Cortisol?
When cortisol is chronically high, it affects the function of various organs in the body as follows:
- Brain: Memory decline / Anxiety / Depression.
- Liver: Produces more sugar.
- Muscle: Muscle loss.
- Fat: Accumulation in the abdomen (Visceral fat).
- Bone: Thinning bones.
- Heart: High blood pressure leading to vascular damage.
- Immune System: Immunodeficiency combined with chronic inflammation.
Immune System: Immunodeficiency combined with chronic inflammation.
| System | Cortisol's Role | Impact of Imbalance |
|---|---|---|
| Stress | Manages stress response | Burnout, Anxiety |
| Metabolism | Boosts energy availability | Weight gain, Insulin resistance |
| Immune | Reduces inflammation | Weakened immunity, Inflammaging |
| Cardiovascular | Regulates blood pressure | Hypertension (High BP) |
| Brain | Controls mood & memory | Brain fog, Depression |
| Bone | Regulates bone turnover | Osteoporosis (Bone loss) |
| Circadian | Controls sleep-wake cycle | Insomnia, Poor sleep quality |
Key Clinical Patterns (Very important for interpretation)
- High Cortisol Pattern: Chronic stress. High Cortisol, Low DHEA, High Insulin, High hs-CRP. Interpretation: Bodily dysfunction caused by stress that accelerates aging (Stress-driven aging), combined with metabolic syndrome and chronic inflammation occurring alongside age-related degeneration (Inflammaging).
- Burnout Pattern (Fatigue from accumulated stress): Because the body’s stress control system is out of balance (HPA dysregulation). Low Cortisol, especially in the morning, Low DHEA. Interpretation: Functional adrenal exhaustion combined with fatigue and poor resilience.
- Burnout Pattern (Fatigue from accumulated stress): Because the body’s stress control system is out of balance (HPA dysregulation). Low Cortisol, especially in the morning, Low DHEA. Interpretation: Functional adrenal exhaustion combined with fatigue and poor resilience.
In-depth Health Analysis Program to view body balance and longevity trends (Functional / Longevity Panel)
Stress and Resilience Longevity Program
- Neuroendocrine: Cortisol (4-point saliva), DHEA-S, ACTH. (Note: Balance equals Resilience).
- Inflammation: Linked to chronic inflammation that accelerates aging (Inflammaging): hs-CRP, ESR.
- Metabolic: Fasting glucose, Insulin, HbA1c. (Note: High Cortisol leads to Insulin resistance).
- Cellular / Aging: Homocysteine, Vitamin B12 / Folate, (Optional) Telomere / Epigenetic markers.
- Cellular / Aging: Homocysteine, Vitamin B12 / Folate, (Optional) Telomere / Epigenetic markers.
Conclusion
Cortisol is not an enemy, but a necessary hormone for survival. Problems arise when it is too high, too low, or secreted at the wrong time (Rhythm is off), which changes it from a “protector” into an “accelerator of degeneration” for every system in the body.
Laboratory Testing
- Basic Stress Panel: Cortisol (AM), DHEA-S, Fasting glucose
- Advanced Longevity Panel: Cortisol (AM/PM or 4-point Saliva), DHEA-S, Lipid profile, Insulin, HbA1c, hs-CRP.
- Longevity Premium: Telomere, Inflammatory cytokines, Epigenetic markers.
Dr. Apakorn Poltian (Medical Technologist)
Reference
- Anagnostis, P., Athyros, V. G., Tziomalos, K., Karagiannis, A., & Mikhailidis, D. P. (2009). The pathogenetic role of cortisol in the metabolic syndrome. Endocrine, 35(2), 121–125.
- Canalis, E., Mazziotti, G., Giustina, A., & Bilezikian, J. P. (2007). Glucocorticoid-induced osteoporosis: Pathophysiology and therapy. Osteoporosis International, 18(10), 1319–1328.
- Epel, E. S., Blackburn, E. H., Lin, J., Dhabhar, F. S., Adler, N. E., Morrow, J. D., & Cawthon, R. M. (2004). Accelerated telomere shortening in response to life stress. Proceedings of the National Academy of Sciences, 101(49), 17312–17315.
- Lupien, S. J., McEwen, B. S., Gunnar, M. R., & Heim, C. (2009). Effects of stress throughout the lifespan on the brain, behaviour and cognition. Nature Reviews Neuroscience, 10(6), 434–445.
- Nader, N., Chrousos, G. P., & Kino, T. (2010). Interactions of the circadian CLOCK system and the HPA axis. Trends in Endocrinology & Metabolism, 21(5), 277–286.
- Sapolsky, R. M., Romero, L. M., & Munck, A. U. (2000). How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions. Endocrine Reviews, 21(1), 55–89.
- Silverman, M. N., & Sternberg, E. M. (2012). Glucocorticoid regulation of inflammation and its functional correlates: From HPA axis to glucocorticoid receptor dysfunction. Annals of the New York Academy of Sciences, 1261(1), 55–63.
- Whitworth, J. A., Mangos, G. J., & Kelly, J. J. (2000). Cushing, cortisol, and cardiovascular disease. Hypertension, 36(5), 912–916.
