Stress Hormone

The primary "stress hormone" is cortisol, produced by the adrenal glands in response to stress or low blood glucose. When the body perceives stress, the hypothalamus signals the adrenal glands to release cortisol, which helps manage stress by increasing blood sugar, enhancing brain use of glucose, and curbing nonessential functions (like digestion) to focus energy on handling the stressor. Cortisol also plays a role in regulating inflammation and immune responses. Other hormones, like adrenaline and norepinephrine, are also released during stress, increasing heart rate and energy levels. While cortisol is essential for coping with stress, prolonged high levels can lead to health issues, including anxiety, depression, weight gain, and immune suppression.

1.0Introduction

Cortisol is a steroid hormone produced and released from adrenal glands( the endocrine glands on top of  kidneys). Cortisol affects several aspects of the body and mainly helps to regulate the body's response to stress. It is one of the glucocorticoids, made in the cortex of the adrenal glands and then released into the blood, which transports it all round the body. Almost every cell contains receptors for cortisol and so cortisol can have lots of different actions depending on which sort of cells it is acting upon. Cortisol is an essential hormone that affects almost every organ and tissue in your body. It plays many important roles, including:

• Regulating your body’s stress response.
• Helping control your body’s use of fats, proteins and carbohydrates, or your metabolism.
• Suppressing inflammation.
• Regulating blood pressure.
• Regulating blood sugar.
• Helping control your sleep-wake cycle.

Cortisol is widely known as the “stress hormone.” However, it has many important effects and functions throughout your body aside from regulating your body’s stress response.

It’s also important to remember that, biologically speaking, there are multiple different kinds of stress, including:

• Acute stress: Acute stress happens when you’re in sudden danger within a short period of time. For example, barely avoiding a car accident or being chased by an animal are situations that cause acute stress.
• Chronic stress: Chronic (long-term) stress happens when you experience ongoing situations that cause frustration or anxiety. For example, having a difficult or frustrating job or having a chronic illness can cause chronic stress.
• Traumatic stress: Traumatic stress happens when you experience a life-threatening event that induces fear and a feeling of helplessness. For example, experiencing an extreme weather event, such as a tornado, or experiencing war or sexual assault can cause traumatic stress. In some cases, these events can lead to post-traumatic stress disorder (PTSD).

2.0Function of cortisol 

Almost all tissues in your body have glucocorticoid receptors. Because of this, cortisol can affect nearly every organ system in your body, including:

• Nervous system.
• Immune system.
• Cardiovascular system.
• Respiratory system.
• Reproductive systems (female and male).
• Musculoskeletal system.
• Integumentary system (skin, hair, nails, glands and nerves).

More specifically, cortisol affects your body in the following ways:

• Regulating your body’s stress response: During times of stress, your body can release cortisol after releasing its “fight or flight” hormones, such as adrenaline, so you continue to stay on high alert. In addition, cortisol triggers the release of glucose (sugar) from your liver for fast energy during times of stress.
• Regulating metabolism: Cortisol helps control how your body uses fats, proteins and carbohydrates for energy.
• Suppressing inflammation: In short spurts, cortisol can boost your immunity by limiting inflammation. However, if you have consistently high levels of cortisol, your body can get used to having too much cortisol in your blood, which can lead to inflammation and a weakened immune system.
• Regulating blood pressure: The exact way in which cortisol regulates blood pressure in humans is unclear. However, elevated levels of cortisol can cause high blood pressure, and lower-than-normal levels of cortisol can cause low blood pressure.
• Increasing and regulating blood sugar: Under normal circumstances, cortisol counterbalances the effect of insulin, a hormone your pancreas makes, to regulate your blood sugar. Cortisol raises blood sugar by releasing stored glucose, while insulin lowers blood sugar. Having chronically high cortisol levels can lead to persistent high blood sugar (hyperglycemia). This can cause Type 2 diabetes.
• Helping control your sleep-wake cycle: Under regular circumstances, you have lower cortisol levels in the evening when you go to sleep and peak levels in the morning right before you wake up. This suggests that cortisol plays a significant role in the initiation of wakefulness and plays a part in your body’s circadian rhythm.

Optimum cortisol levels are necessary for life and for maintaining several bodily functions. If you have consistently high or low cortisol levels, it can have negative impacts on your overall health.

3.0Normal  cortisol levels

• The body has an elaborate system to regulate your cortisol levels.
• Hypothalamus, a small area of your brain involved in hormonal regulation, and your pituitary gland, a tiny gland located below your brain, regulate the production of cortisol in your adrenal glands. When the levels of cortisol in your blood fall, your hypothalamus releases corticotropin-releasing hormone (CRH), which directs your pituitary gland to produce adrenocorticotropic hormone (ACTH). ACTH then stimulates your adrenal glands to produce and release cortisol.
• In order to have optimal levels of cortisol in your body, your hypothalamus, pituitary gland and adrenal glands must all be functioning properly.

It can be measured  in  blood, urine  and saliva (spit) tests.

The level of cortisol in blood, urine and saliva normally peaks in the early morning and declines throughout the day, reaching its lowest level around midnight. This pattern can change if you work a night shift and sleep at different times of the day.

For most tests that measure cortisol levels in your blood, the normal ranges are:

• 6 a.m. to 8 a.m.: 10 to 20 micrograms per deciliter (mcg/dL).
• Around 4 p.m.: 3 to 10 mcg/dL.

4.0High levels of cortisol

Experiencing abnormally high levels of cortisol (hypercortisolism) for an extended period of time is usually considered Cushing’s syndrome, which is a rare condition. Causes of higher-than-normal cortisol levels and Cushing’s syndrome include:

• Taking large amounts of corticosteroid medications, such as prednisone, prednisolone or dexamethasone, for treatment of other conditions.
• Tumors that produce adrenocorticotropic hormone (ACTH). These are usually found in your pituitary gland. More rarely, neuroendocrine tumors in other parts of your body such as your lungs can cause high cortisol levels.
• Adrenal gland tumors or excessive growth of adrenal tissue (hyperplasia), which cause excess production of cortisol.

5.0What are the symptoms of high cortisol levels?

The symptoms of Cushing’s syndrome depend on how elevated your cortisol levels are. Common signs and symptoms of higher-than-normal cortisol levels include:

• Weight gain, especially in your face and abdomen.
• Fatty deposits between your shoulder blades.
• Wide, purple stretch marks on your abdomen (belly).
• Muscle weakness in your upper arms and thighs.
• High blood sugar, which often turns into Type 2 diabetes.
• High blood pressure (hypertension).
• Excessive hair growth (hirsutism) in people assigned female at birth.
• Weak bones (osteoporosis) and fractures.

6.0Low levels of cortisol

Having lower-than-normal cortisol levels (hypocortisolism) is considered adrenal insufficiency. There are two types of adrenal insufficiency: primary and secondary. The causes of adrenal insufficiency include:

• Primary adrenal insufficiency: Primary adrenal insufficiency is most commonly caused by an autoimmune reaction in which the immune system attacks healthy cells in  adrenal glands for no known reason. This is called Addison’s disease.  Adrenal glands can also become damaged from an infection or blood loss to the tissues (adrenal hemorrhage). All of these situations limit cortisol production.
• Secondary adrenal insufficiency:  underactive pituitary gland (hypopituitarism) or a pituitary tumor, it can limit ACTH production. ACTH signals your adrenal glands to make cortisol, so limited ACTH results in limited cortisol production.

Symptoms of lower-than-normal cortisol levels, or adrenal insufficiency, include:

• Fatigue.
• Unintentional weight loss.
• Poor appetite.
• Low blood pressure (hypotension).

7.0Control of cortisol

• Cushing’s syndrome (very high levels of cortisol) needs medical treatment to lower your cortisol levels. Treatment usually involves medication and/or surgery. 
• In general, though, there are several everyday things you can do to try to lower your cortisol levels and keep them at optimal ranges, including:
• Get quality sleep: Chronic sleep issues, such as obstructive sleep apnea, insomnia or working a night shift, are associated with higher cortisol levels.
• Exercise regularly: Several studies have shown that regular exercise helps improve sleep quality and reduce stress, which can help lower cortisol levels over time.
• Learn to limit stress and stressful thinking patterns: Being aware of your thinking pattern, breathing, heart rate and other signs of tension helps you recognize stress when it begins and can help you prevent it from becoming worse.
• Practice deep breathing exercises: Controlled breathing helps stimulate your parasympathetic nervous system, your “rest and digest” system, which helps lower cortisol levels.
• Enjoy yourself and laugh: Laughing promotes the release of endorphins and suppresses cortisol. Participating in hobbies and fun activities can also promote feelings of well-being, which may lower your cortisol levels.
• Maintain healthy relationships: Relationships are a significant aspect of our lives. Having tense and unhealthy relationships with loved ones or coworkers can cause frequent stress and raise your cortisol levels.

8.0Sample Question on Stress Hormone

Q.1 What are the symptoms of Cushing's syndrome

Ans.

The symptoms of Cushing’s syndrome depend on how elevated your cortisol levels are. Common signs and symptoms of higher-than-normal cortisol levels include:

• Weight gain, especially in your face and abdomen.
• Fatty deposits between your shoulder blades.
• Wide, purple stretch marks on your abdomen (belly).
• Muscle weakness in your upper arms and thighs.
• High blood sugar, which often turns into Type 2 diabetes.
• High blood pressure (hypertension).
• Excessive hair growth (hirsutism) in people assigned female at birth.
• Weak bones (osteoporosis) and fractures.