Adrenal Function and Cortisol As They Relate To Adrenal Fatigue

By Lisa Wells, RN

Adrenal function and stress

What Are the Adrenal Glands?

The adrenal glands are two small glands with each located just above a kidney. They release powerful steroid hormones that are responsible for important life sustaining processes such as keeping salt and water in the body balanced, keeping blood pressure normal, regulating blood glucose, keeping thyroid function optimum, and their good function is required for a strong and healthy immune system.

Another important job they have is helping us to cope with all types of stress, both psychological and physical.

The adrenal glands make cortisol, pregnenolone, DHEA, aldosterone, epinephrine, and norepinephrine. They also assist in the production of the gonad hormones progesterone, testosterone, and the estrogens (estradiol, estriol, estrone) by converting pregnenolone into progesterone, and converting DHEA into testosterone and the estrogens as is needed to help to keep their levels optimum. As age progresses and the ovaries and testes decrease their release of these hormones the adrenal glands become responsible for more of their release.

Our energy, endurance, ability to fight infection, ability to heal and rejuvenate, and in fact our very lives depend upon the proper functioning of the adrenal glands.

Cortisol - The Hormone For Stress

Cortisol is a very important steroid hormone that we can't live without. It is made in the cortex of the two adrenal glands. It protects us from all types of stress including infection, overwork, intense exercise, low calorie intake, and emotional stress. It is required for the proper functioning of about all processes of the body so we must maintain an adequate supply, however, having constant high levels of cortisol can also be detrimental to health.

Important Functions of Cortisol

Helps to provide energy and strength in times of emergency
Helps to protect the body from the effects of all types of stress
Regulates blood glucose and insulin and helps to prevent hypoglycemia
Increases cardiac output
Helps to sustain blood pressure and prevent hypotension
Stimulates red blood cell production
Necessary for proper thyroid function
Is required for the proper conversion of the storage thyroid hormone T4 into active T3
Is required for the active thyroid hormone T3 to enter the cell receptors
Acts as a natural anti-inflammatory
Is required for proper immune function
Helps to regulate kidney function
Required for the proper metabolism of protein, fats, and carbohydrates

Adrenal Fatigue

Adrenal fatigue, also called adrenal exhaustion, is a condition where the adrenal glands are no longer able to produce enough cortisol to sustain good health.

The Effects of Low Cortisol

Unable to tolerate stress
Fatigue, especially in the morning
Poor sleep quality, can't stay asleep
Lack of energy
Sugar cravings
Muscle weakness
Low stamina
Slow recovery after exertion
Feeling light headed when standing up quickly
Hypotension (low blood pressure)
Hypoglycemia (low blood sugar)
Weakened immune system
Frequent colds and illnesses
Slow recovery from illness
Decreased sex drive
Decreased reproductive ability
Brain fogginess, decreased memory
Depression, anxiety
Lack of interest in things
Salt cravings

Some Causes of Low Cortisol

All Types of Stress

The adrenal glands of some people may fail after an acute infection or illness. For others it may be a major psychological factor or change in life that causes the problem.

Working long hours in stressful jobs over many years can be another cause.

Underlying Infections and Toxins

There can also be lesser known and harder to pinpoint causes. An example would be a mild chronic infection in a tooth that has had a root canal. The tooth may not hurt but the body's immune system knows the infection is there and has to deal with it every day and so that is stress that can eventually tire the adrenal glands.

Toxins in the body also stress the immune system and so can have a negative effect on adrenal function. An example is the mercury that is contained in the amalgam that is used for teeth fillings. This mercury can end up in the patient's body tissue and blood.

Vitamin and Mineral Deficiencies

Another cause of decreased adrenal function and low cortisol levels may be vitamin and mineral deficiencies. These vitamins and minerals are required for the adrenal glands to function properly.

Vitamin C
Pantothenic Acid (Vitamin B5)
Niacin (Vitamin B3)
Vitamin B Complex
Trace Minerals (Selenium, Zinc, Chromium, Copper, Iodine, Manganese, Molybdenum)
Vitamin D3
Vitamin E (Tocopherols and Tocotreniols)
Vitamin K2

Important: Low cortisol can be a life threatening situation so people with serious adrenal insufficiency may be prescribed a hydrocortisone injection kit that they are to keep with them at all times.

High Cortisol

The human body is equipped to handle high levels of cortisol only for a short time, such as part of the "fight or flight" reaction to danger. Non-stop or recurring stress can lead to cortisol remaining elevated over an extended period of time. Long term elevated cortisol levels can cause serious health problems. It can lead to adrenal fatigue and in fact in stage 1 adrenal fatigue the cortisol level can be high at times.

Chronically elevated cortisol will cause the body to break down.

The Effects of High Cortisol

Weight gain
Increased fat in the mid section and abdominal area but not in the extremities
Increased appetite
Increased blood sugar levels
Decreased libido
Muscle loss
Poor muscle tone
Bone loss
Immune system suppression
Moon shaped face in extreme cases

As previously stated, in stage 1 of adrenal fatigue the cortisol level is usually high. If this is not corrected it can lead to stage 2 which is the point where the constant overwork begins to wear the adrenal glands out so they are less and less able to make enough cortisol.

The natural rhythm of cortisol is for it to be at its highest level in the morning and then slowly decrease throughout the day and be at its lowest at night. However, some people may have low cortisol during the day and high cortisol during the night. High night-time cortisol levels may be related to the patient becoming hypoglycemic during the night.

How To Check Your Cortisol Levels

Those who suspect they may have an issue with their adrenal glands and cortisol levels should ask their doctor to check their levels. If doing a blood test the doctor should order:

Cortisol and DHEA levels at 8 AM.
Repeat Cortisol level at 4 PM on the same day as the 8 AM test.

Cortisol should be checked at least twice on the same day and it is important to have the blood drawn around 8 AM and 4 PM on that day. DHEA may or may not be repeated at 4 PM but it should at least be checked once along with the 8 AM blood draw.

A better and more accurate test for cortisol and DHEA is the saliva test. The best is the saliva test that checks the cortisol and DHEA level at 8 AM and then cortisol is checked again at 12 PM, 4 PM and 8 PM. That's four times on the same day.

Cortisol levels should naturally change throughout the day and that is why it should be checked several times during the same day.

If the cortisol level is only checked once in the morning the results may be normal. If the doctor stops there he/she may think the patient is fine, but if the level had been rechecked at 4 PM it may have told the story of what is happening, which is that the patient's adrenals are wearing out as the day progresses.

The saliva test that checks the cortisol level at four different times during one day is also better at diagnosing the patient who has high cortisol levels at night. Since the saliva test is done by the patient at home the last test time can be done at 8 PM or later.

During my own experience with adrenal exhaustion I could not stay asleep at night. It seemed that around 2 or 3 AM I would wake up hungry, with my heart pounding, and I would need to eat something sweet in order to go back to sleep. One night when I awoke I checked my blood sugar and found that my cortisol level was increasing at night due to me becoming hypoglycemic while asleep. This actually happens as a safety mechanism. Cortisol is released in order to convert glycogen in the liver into glucose, thus bringing the glucose level back up.


For optimal health the adrenal glands need to be strong and rested and cortisol levels need to be balanced. Otherwise the systems of the body cannot function properly. For this reason I recommend those who have been under much stress and have been feeling run down and easily fatigued lately educate themselves and take action.

It is unfortunate but MD's are not taught about adrenal fatigue during their medical training. They are only taught about the extreme adrenal diseases called Addison's Disease and Cushing's Syndrome. It is estimated by some alternative doctors that millions of people are living with overworked and tired adrenals, and we know that this can cause all types of health issues. Adrenal dysfunction can be the underlying or contributing cause of serious health conditions so it should not be taken lightly.

Recommended Reading

Hypothyroidism - the Undiagnosed and Treatment Failures

Thyroid Autoimmune Disorders - the Most Common Cause of Thyroid Dysfunction

How Human Growth Hormone (HGH) May Affect and Improve Thyroid Function

Hormones That Decrease With Age and Your Options

More Health Articles by Lisa Wells, RN




Wilson, James L., "Adrenal Fatigue The 21st Century Stress Syndrome," Smart Publications, First Edition, Thirteenth Printing, 2009.