Low Cortisol Levels: Causes and Effects
Medically reviewed by Gareth James, GP, GMC, DRCOG, DFFP, MRCGP on March 31, 2023. To give you technically accurate, evidence-based information, content published on the Check My Body Health blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.
Cortisol is a steroid hormone produced by the adrenal glands that plays a number of important roles in the body. Its main function is to help the body respond to stress.
Low cortisol levels can be caused by a variety of factors, including stress, certain medical conditions (such as Addison’s disease, congenital adrenal hyperplasia or pituitary tumors), and medications (such as glucocorticoid therapy or anti-fungals). In some cases, the cause of low cortisol levels may be unknown.
What does cortisol do in the body?
- Regulating metabolism: Cortisol helps to regulate blood sugar levels and the metabolism of fat, protein, and carbohydrates.
- Responding to stress: Cortisol is often referred to as the “stress hormone” because it is released in response to stress and helps the body to respond to and recover from stressful situations.
- Controlling inflammation: Cortisol acts as an anti-inflammatory agent, helping to reduce inflammation throughout the body.
- Regulating blood pressure: Cortisol helps to regulate blood pressure by causing blood vessels to constrict, which increases blood pressure.
- Influencing the immune system: Cortisol can suppress the immune system, helping to prevent an overactive immune response.
- Supporting cognitive function: Cortisol helps to support cognitive function by promoting the formation of new memories and helping to regulate the sleep-wake cycle.
It’s important to note that cortisol level fluctuates throughout the day, usually is high in the morning and low at night. Ongoing chronic stress can lead to cortisol dysregulation which can have negative effects on the body.
What causes low cortisol levels?
Low cortisol levels can be caused by a variety of factors, including:
- Medical conditions: Certain medical conditions can cause low cortisol levels, such as Addison’s disease (which is an autoimmune disorder that affects the adrenal glands), congenital adrenal hyperplasia (which is a genetic disorder that affects the adrenal glands), and pituitary gland tumours (which can damage the pituitary and affect the production of hormones such as cortisol).
- Medications: Some medications can lower cortisol levels, such as glucocorticoid therapy, which are used to treat conditions such as inflammation and autoimmune disorders, and ketoconazole, which is an antifungal medication.
- Stress: Ongoing chronic stress can lead to cortisol dysregulation, which can result in low cortisol levels.
- Malnutrition: Malnutrition can cause low cortisol levels, as the body may not have enough nutrients to produce adequate amounts of cortisol.
- Genetic predisposition: Some people may have a genetic predisposition to low cortisol levels.
- Other illnesses: Certain illnesses or infections such as sepsis, tuberculosis, and fungal infections can also cause low cortisol levels.
In some cases, the cause of low cortisol levels may be unknown. It’s important to consult with a doctor if you have symptoms of low cortisol levels, such as fatigue, weakness, weight loss, and low blood pressure.
What is Addison’s disease
Addison’s disease, also known as primary adrenal insufficiency, is a rare, chronic endocrine disorder that affects the adrenal glands. The adrenal glands are small glands located on top of each kidney that produce hormones, including cortisol and aldosterone.
In Addison’s disease, the adrenal glands do not produce enough of these hormones, leading to a variety of symptoms. The most common symptoms are fatigue, weakness, weight loss, and low blood pressure. Other symptoms can include nausea, vomiting, diarrhoea, darkening of the skin (due to hyperpigmentation), and salt cravings.
Addison’s disease can occur as a result of an autoimmune disorder, infection, or injury to the adrenal glands. In some cases, the cause of Addison’s disease may be unknown.
Addison’s disease is diagnosed through a combination of blood tests, physical examination, and imaging studies. Treatment for Addison’s disease typically involves taking replacement doses of hormones, such as cortisol and aldosterone, to replace the hormones that the adrenal glands are not producing.
Addison’s disease is a chronic condition that usually requires lifelong hormone replacement therapy. It’s important to work closely with a healthcare provider to manage the condition and avoid complications.
What are the Signs and symptoms of Addison’s disease
The signs and symptoms of Addison’s disease can vary and may develop gradually over time. Common signs and symptoms include:
Fatigue: People with Addison’s disease may feel tired, weak, and have a lack of energy.
Weight loss: Unexplained weight loss is a common symptom, despite a normal or increased appetite.
Low blood pressure: Addison’s disease can cause low blood pressure, which can lead to dizziness or fainting.
Abdominal pain: Some people may experience abdominal pain, nausea, vomiting, or diarrhoea.
Skin changes: The skin may darken, especially in areas exposed to the sun, such as the face, hands, and feet.
Salt cravings: People with Addison’s disease may have an intense craving for salt, which can lead to excessive salt intake.
Mood changes: Addison’s disease can cause mood changes, such as depression or anxiety.
Muscular weakness: People may experience muscle weakness, making it difficult to lift objects or walk.
Hypoglycemia: Low blood sugar can occur due to the lack of cortisol, symptoms include shakiness, sweating, and confusion.
It’s important to note that these symptoms can be caused by other conditions as well, and a definitive diagnosis of Addison’s disease requires a combination of blood tests, physical examination, and imaging studies. If you suspect you may have Addison’s disease, it’s important to consult with a healthcare provider.
Can you have too much cortisol
Yes, it is possible to have too much cortisol in the body, a condition known as Cushing’s syndrome (also known as hypercortisolism). This can happen when the body is exposed to high levels of cortisol for an extended period of time, which can be caused by a variety of factors including:
Medications: Certain medications such as glucocorticoids, used to treat conditions such as inflammation and autoimmune disorders, can lead to excessive cortisol levels if taken in high doses or for long periods of time.
Stress: Chronic stress can lead to cortisol dysregulation, which can result in high cortisol levels.
Tumours: Tumours in the pituitary gland or adrenal glands can overproduce cortisol.
Symptoms of high cortisol levels can include weight gain, particularly around the face (giving a classical ‘moon face’ appearance) and back (giving what’s described as a ‘buffalo hump’) whilst central obesity occurs with slim legs and arms. Also seen are skin changes such as easy bruising and stretch marks, muscle weakness, high blood pressure, diabetes and osteoporosis. People may also experience anxiety, depression, and fatigue.
It’s important to consult with a healthcare provider if you suspect you may have hypercortisolism. The diagnosis is typically made through a combination of blood tests, imaging studies, and physical examination. Treatment options include surgery, radiation therapy, and medication.
Can I test for cortisol levels?
There are several tests that can be used to measure cortisol levels in the body. These tests are frequently undertaken in secondary care under a consultant endocrinologist:
Blood test: A blood sample is taken and analysed for cortisol levels. This test can be done at any time of the day, but it may not provide a complete picture of cortisol levels throughout the day.
Saliva test: A saliva sample is collected and analysed for cortisol levels. This test can be done at home, and it can provide a more detailed picture of cortisol levels throughout the day.
Urine test: A urine sample is collected and analysed for cortisol levels. This test can provide a more detailed picture of cortisol levels over the course of several days.
Dexamethasone suppression test: A low dose of the synthetic glucocorticoid, dexamethasone, is administered with cortisol levels measured before and after. This test is used to determine if there is a dysfunction in the feedback mechanism that regulates cortisol production.
It’s important to note that the test chosen and the timing of the test may vary depending on the suspected cause of the cortisol imbalance and the symptoms the individual is experiencing. A healthcare provider can advise on the appropriate test and timing.
- Thau L, Gandhi J, Sharma S. Physiology, Cortisol. [Updated 2020 May 29]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. (https://www.ncbi.nlm.nih.gov/books/NBK538239/)
- Huecker MR, Dominique E. Adrenal Insufficiency. [Updated 2020 Oct 15]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. (https://www.ncbi.nlm.nih.gov/books/NBK441832/)
- Addison Disease. Merck Manual. Accessed September 13, 2020. (https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/adrenal-disorders/addison-disease)
- Adrenal Insufficiency (Addison’s Disease). John’s Hopkins. Accessed September 13, 2020. (https://www.hopkinsmedicine.org/health/conditions-and-diseases/underactive-adrenal-glands–addisons-disease)
- Addison’s Disease. Mayo Clinic. Accessed September 13, 2020. (https://www.mayoclinic.org/diseases-conditions/addisons-disease/symptoms-causes/syc-20350293)
- Nicolaides NC, Chrousos GP, Charmandari E. Adrenal Insufficiency. [Updated 2017 Oct 14]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. (https://www.ncbi.nlm.nih.gov/books/NBK279083/)
- Symptoms and Causes of Adrenal Insufficiency & Addison’s Disease. NIH. Accessed September 13, 2020. (https://www.niddk.nih.gov/health-information/endocrine-diseases/adrenal-insufficiency-addisons-disease/symptoms-causes)
- Cushing syndrome. Mayo Clinic. Accessed September 13, 2020. (https://www.mayoclinic.org/diseases-conditions/cushing-syndrome/symptoms-causes/syc-20351310)
- Corticotrophin-releasing hormone. You and Your Hormones from The Society of Endocrinology. Accessed September 13, 2020. (https://www.yourhormones.info/hormones/corticotrophin-releasing-hormone/)