What is adrenal fatigue?
Adrenal fatigue is a term applied to a collection of nonspecific symptoms such as body aches, fatigue, nervousness, sleep disturbances and digestive problems. The term often shows up in popular health books and on alternative medicine websites, but it isn’t an accepted medical diagnosis.
Some healthcare providers say adrenal fatigue is a real medical condition caused by chronic stress. But the majority of endocrinologists say there’s no solid evidence linking adrenal fatigue to any abnormality with the adrenal glands. Still, many people cling to the concept because it offers a quick, tidy explanation for feeling fatigued or rundown.
What do the adrenal glands do?
Your adrenal glands produce hormones that help regulate your body’s functions and manage stress. The hormones produced by the adrenal glands include:
– Cortisol. Often called the stress hormone, cortisol helps maintain proper glucose metabolism, blood pressure and insulin release.
– Aldosterone. This hormone helps regulate your blood pressure and the balance of sodium and potassium in your blood.
– Adrenaline. Also called epinephrine, adrenaline increases your heart rate, breathing rate and blood pressure. This “fight or flight” hormone prepares your body to deal with perceived danger.
– Dehydroepiandrosterone (DHEA). A male sex hormone produced in small amounts by the adrenal glands, DHEA serves as a precursor to male and female sex hormones.
The amount of cortisol produced by your adrenal glands is precisely calibrated. Normally, levels are highest in the early morning and lowest around midnight. Factors such as stress, low blood glucose, infections and surgery can cause your cortisol levels to spike.
If your adrenal glands produce too much cortisol, you may develop Cushing’s syndrome — a rare endocrine system disorder. If your adrenal glands don’t produce enough cortisol, you may develop Addison’s disease — also a rare disorder.
More commonly, something might temporarily interfere with adrenal gland function, such as:
– Stopping or taking certain medications, such as corticosteroids
– Dehydration
– Stress from an injury or severe infection
– Surgery involving the adrenal glands
Symptoms usually resolve once the underlying cause is corrected.
What are the claims behind adrenal fatigue?
Some practitioners claim that relentless mental, emotional, physical or metabolic stress taxes the adrenal glands, causing below-normal levels of hormones. This alleged adrenal weakness or insufficiency results in vague, nonspecific symptoms:
– Fatigue
– Body aches
– Low stamina
– Difficulty concentrating
– Irritability
– Poor sleep
According to this theory, restoring adrenal health requires removing sources of stress, dietary changes, nutritional supplements, herbal remedies and lifestyle modifications. Treatment must be individualized and often takes months. Yet advocates claim most people with adrenal fatigue will have improved energy levels and reduced symptoms with proper treatment.
Is there any research to support adrenal fatigue?
A landmark paper published in 2015 reviewed the evidence for diagnosing adrenal fatigue. The authors found no proof that foggy thinking, extreme fatigue, nervousness or other nonspecific symptoms are connected to weakness in the adrenal glands. Measurements of cortisol levels in blood or saliva revealed no significant difference between healthy individuals and those said to have adrenal fatigue.
In short, science has found no indication that symptoms attributed to adrenal fatigue correlate with any problem in adrenal gland function. As the 2015 paper concluded, adrenal fatigue is a mythical diagnosis without a real biomarker or proven scientific basis.
Why not just do an adrenal test?
At first glance, getting tested for adrenal fatigue seems reasonable. But current adrenal tests have limitations that make them unreliable for diagnosing subtle problems, if they exist at all.
An endocrinologist may order tests to evaluate adrenal gland function if you have symptoms of an adrenal disorder, such as Cushing’s syndrome or Addison’s disease. The tests help determine if your symptoms stem from high or low cortisol levels. These adrenal tests include:
– Cortisol level at a single point in time. This blood or saliva test measures your cortisol level at a specific moment. Cortisol levels normally fluctuate throughout the day, making single results hard to interpret. Normal and abnormal levels overlap too much, limiting the test’s usefulness.
– 24-hour urinary free cortisol. You collect your urine for a full day and night. The laboratory measures how much cortisol you excreted over the 24-hour period. This assesses your overall daily production of cortisol.
– Cortisol stimulation test. This test uses a synthetic hormone to directly stimulate your adrenal glands. Blood samples before and after the stimulant help determine if your adrenal glands responded normally.
-dexamethasone suppression test. You take dexamethasone, a synthetic cortisollike drug, before having your blood cortisol measured. Normally, dexamethasone suppresses natural cortisol production. If it does not, it can indicate Cushing’s syndrome.
– Adrenal antibodies test. This blood test looks for antibodies associated with autoimmune diseases that target the adrenal glands, such as Addison’s disease.
Limitations of adrenal function testing
While these adrenal tests can help diagnose Cushing’s, Addison’s and other pronounced adrenal disorders, they have significant limitations:
– Results vary widely even in healthy adults. A given test result might be normal for one person but abnormal for someone else.
– Cortisol levels fluctuate during the day and with stress, diet, exercise, illness and other influences. A test gives only a snapshot in time.
– No standard reference ranges exist for what’s “normal.” Different laboratories use different cutoff values.
– Factors such as natural fluctuations and stress during testing can affect results.
– The tests involve complex multi-step processes prone to errors.
According to The Endocrine Society and other major medical organizations, current tests lack the sensitivity needed to detect the subtle changes proposed in adrenal fatigue — if those abnormalities even exist.
Conclusion
Despite claims about testing for and treating adrenal fatigue, most experts argue there’s insufficient scientific evidence that adrenal fatigue is a distinct medical condition. Legitimate disorders that affect the adrenal glands are quite rare.
In general, major medical organizations haven’t accepted adrenal fatigue as a diagnosis because no defining signs or symptoms have been reliably linked to biochemical abnormalities in the adrenal glands. Testing also lacks the precision to detect small variations in hormone levels — if variations do occur with adrenal fatigue.
Proponents claim the adrenal fatigue diagnosis fills a gap and guides individualized treatment plans that eventually make people feel better. But established medical organizations counter that the label lacks a genuine physiological basis. They argue that general lifestyle measures like reducing stress, eating healthy, exercising, and getting sufficient sleep can help combat nonspecific symptoms often attributed to adrenal fatigue.