Adrenal fatigue

What is adrenal fatigue?

Adrenal fatigue is a theory that long-term stress can cause the adrenal glands to stop working properly, causing symptoms such as tiredness or fatigue.

However, there is no scientific evidence that this actually happens.

The Endocrine Society (the international society that represents endocrinologists, or hormone specialist doctors) states that no scientific proof exists to support adrenal fatigue as a true medical condition. This is the consensus opinion amongst mainstream endocrinologists and other conventional medicine practitioners.

Adrenal fatigue is a term sometimes used by alternative medicine practitioners. Doctors, though, are concerned that using this term is not accurate, and may miss the true cause of the symptoms. Some of the treatments offered may also be dangerous.

Adrenal fatigue shouldn't be confused with adrenal insufficiency or Addison's disease. Adrenal insufficiency and Addison's disease are recognised medical conditions, which can be life-threatening. You can read more about these conditions in the Addison's disease leaflet.

What are the symptoms of adrenal fatigue?

Supporters of adrenal fatigue theory believe that adrenal fatigue causes tiredness, fatigue, and exhaustion.

Other suggested symptoms include:

• Finding it difficult at times to think clearly.

• Feeling as though you are unable to function properly and complete tasks.

• Craving sweet or salty foods and drinks.

• Needing to drink coffee or other stimulant drinks frequently to help you feel more awake.

• Feeling dizzy.

• Having a low sex drive.

• Gaining weight.

However, sceptics of adrenal fatigue - including most doctors - say that these are 'non-specific' symptoms, meaning that they can be caused by lots of different things, and do not clearly indicate one specific diagnosis.

There are lots of possible diagnoses that can cause non-specific symptoms. Sometimes they have no clear cause.

What causes adrenal fatigue?

The adrenal glands are a pair of organs found just above the kidneys on both sides. They are small (about the size of a walnut in adults) but vital organs. The adrenal glands produce hormones, of which the most important ones are:

• Cortisol, which has lots of very important functions, such as controlling blood sugar, controlling salt levels in the blood, and affecting the function of the immune function.

• Aldosterone, which is very important for controlling salt (sodium and potassium) levels in the blood, and controlling blood pressure.

• Androgens (like testosterone and other related hormones), which have important effects in both men and women.

• Adrenaline (epinephrine), which is crucial for the body's 'fight or flight' response to danger or stress.

These hormones are essential for life. People with adrenal insufficiency or Addison's disease are unable to make enough adrenal hormones, which can be life-threatening.

Cortisol is often called a 'stress hormone', because it increases as part of the body's response to stress or danger.

The theory behind adrenal fatigue is that long-term emotional, physical, or mental stress can cause the adrenal glands to become 'exhausted', meaning they can no longer produce enough adrenal hormones, and leading to symptoms such as exhaustion.

However, there is no good scientific evidence to support this theory.

Instead, there are probably other reasons why people with long-term stress experience symptoms said to be due to adrenal fatigue.

These symptoms are real. But the explanation for them is likely to be something different, such as poor sleep, poor diet, psychological issues such as depression or anxiety, or other medical conditions such as an underactive thyroid.

How is adrenal fatigue diagnosed?

Various tests have been proposed to diagnose adrenal fatigue. But none of them have been shown to be useful or abnormal in people who are said to have adrenal fatigue.

Cortisol levels can be measured in blood, saliva, and urine tests. There are also tests that measure the adrenal glands' ability to produce hormones in response to a stimulus, such as another hormone or a medication.

These tests are abnormal in people who have adrenal insufficiency or Addison's disease, and in conditions where the adrenal glands are producing too much hormones, such as Cushing's syndrome.

However, these tests are normal in people who are said to have adrenal fatigue.

Other tests are sometimes offered to test for adrenal fatigue, but there is no good scientific evidence that these tests are reliable or useful.

Research studies have never clearly shown evidence of abnormal hormonal changes in people who are said to have adrenal fatigue, which is a major reason why mainstream doctors think that adrenal fatigue does not exist as a true disease.

Supporters of adrenal fatigue theory claim that currently-available diagnostic tests are not sensitive enough to pick up hormonal changes in adrenal fatigue, but that these hormonal changes still exist and cause symptoms. There is no good scientific evidence to support this claim.

What is the treatment for adrenal fatigue?

Adrenal fatigue isn't recognised as a medical condition, and so mainstream doctors don't endorse specific treatments for it.

Some people do promote certain treatments for adrenal fatigue.

Some of these suggestions are helpful for almost everyone's health and wellbeing, and are a good idea to try for stress-related symptoms regardless of whether adrenal fatigue theory is correct or not.

Other treatment suggestions are not recommended, and may be harmful.

Reducing stress levels

Reducing stress levels is helpful for everyone. See also the separate leaflets called Acute stress reaction and Stress management and also the leaflet called Relaxation exercises.

Eating a healthy diet

A healthy diet is important for everyone. Eat plenty of fruit and vegetables. Avoid junk foods and processed foods. Also avoid or reduce coffee and any other stimulant drinks and reduce your intake of sugary drinks and foods. See also the separate leaflet called Healthy eating.

Exercising regularly

Regular exercise is good for health and wellbeing, and most people feel better when they exercise regularly. See the separate leaflet called Exercise and physical activity.

People with conditions such as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and long Covid may find that over-exertion through exercise makes their symptoms worse, and should be careful to pace themselves when exercising. See the ME/CFS and long Covid leaflets for more detail.

Getting enough sleep

Poor sleep can make people feel exhausted. It is very important to have enough sleep and to stick to a consistent sleep routine. For more information see the separate leaflet called Insomnia (Poor sleep) and the leaflet called Sleep diary.

Treatments that aren't recommended

Some people recommend vitamins or herbal supplements for adrenal fatigue.

There is no evidence that these are helpful, and they may be harmful, particularly as they may be unregulated and contain dangerous ingredients or impurities.

Sometimes adrenal hormone supplements are offered, like medications such as hydrocortisone.

Whilst these are an essential treatment for conditions such as adrenal insufficiency, there is no evidence that they are helpful in people who are said to have adrenal fatigue. They also have major side-effects and harms, such as causing bone thinning (osteoporosis), diabetes, and weight gain.

Taking extra adrenal hormones for a long time also causes the adrenal glands to shut down their production of adrenal hormones, causing the body to become dependent on the hormone drugs. This means that stopping adrenal hormone drugs suddenly can be very dangerous.