Could tired adrenals be the cause of your fatigue?

Unexplained tiredness is one of the leading reasons people visit their GP(1). According to the Royal College of Psychiatrists, 1 in every 5 individuals feels especially tired, while 1 in 10 experience prolonged fatigue(2).

Once a specific cause such as anaemia or thyroid dysfunction has been ruled out, individuals are often advised to consider more sleep, exercise and even the occasional use of stimulants to get them through the day(3).

But what if the fatigue is not relieved by sleep, and exercise makes it worse? What if the exhaustion is coupled with an inability to cope with daily stressors and increased feelings of anxiety or brain fog?

While still a controversial topic in medical practice, a steep rise in the above symptoms has led many naturopathic and integrative practitioners to look to the adrenals for an answer, in a condition coined ‘adrenal fatigue’.

Today we will discuss the basic functions of the adrenal glands, their importance in the body and the role that prolonged stress may play in the development of adrenal fatigue. Furthermore, we will explore the health implications of adrenal dysregulation, as well as the controversy surrounding this condition.

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What are the adrenals and why are they so important?

The adrenals or suprarenals are two small glands which sit above the kidneys. These glands are required to support the production of numerous crucial hormones which are involved in almost every bodily function. Each gland has an outer cortex responsible for producing steroid and sex hormones such as aldosterone, cortisol, DHEA, oestrogen and testosterone; as well as an inner medulla which secretes catecholamines such as adrenaline, noradrenaline and small amounts of dopamine. Cortisol, DHEA and adrenaline are the key adrenal stress hormones which support the body in managing stress and adapting to daily demands.

The hypothalamic-pituitary-adrenal (HPA) axis is a central part of the hormonal network where the adrenals interact closely with the pituitary gland and the hypothalamus.  The HPA axis is responsible for neuroendocrine adaptation during the stress response. When a stressor is detected, the hypothalamus releases corticotropin-releasing hormone (CRH), which binds to CRH receptors on the anterior pituitary gland. This triggers the release of adrenocorticotropic hormone (ACTH) which binds to receptors on the adrenal cortex and stimulates adrenal release of cortisol. Once a certain blood concentration is reached, cortisol should exert a negative feedback to the hypothalamic release of CRH. In the case of chronic stress, the repeated and sustained activation of the HPA axis can contribute to hyperactivity of this response which has been linked to immune, metabolic and psychiatric dysfunction(4).

Under normal conditions, the adrenals should work on a diurnal rhythm by which bursts of cortisol are released throughout the day to keep the body awake, while naturally declining towards the evening in preparation for sleep. Although, research has demonstrated that this rhythm is highly susceptible to external stressors(5,6).

What is adrenal fatigue?

The term ‘adrenal fatigue’ is used to explain a group of symptoms which may be observed in individuals who are under long-term physical and/or psychological stress.

Symptoms include(7):

  • Prolonged or excessive tiredness
  • Difficulty waking in the morning or falling asleep at night
  • Inability to cope with stress
  • Dependency on stimulants such as caffeine or sugar to get through the day
  • Strong salt and/or sugar cravings

Stress normally causes the adrenals to increase their output of cortisol and DHEA; while adrenaline is secreted to boost the energy one might require for short-term survival i.e. when running from a threat. However, when this state is needed for a prolonged period; for example when stress becomes chronic, the adrenals may struggle to maintain the output for such a high demand of steroid hormones which could result in a drop in DHEA and cortisol levels(8–10).

A commonly observed pattern for adrenal fatigue is the presence of fatigue upon waking, often with a requirement for stimulants to gain energy during the morning. Energy levels might crash again in the afternoon and rise in the early evening. Cortisol may be raised before sleep causing difficulty in falling asleep. For those with more advanced adrenal fatigue, cortisol output may be consistently low and so exhaustion can be a constant throughout the day(7).

The body’s biological stress or ‘fight or flight’ response has been designed to shut down all non-essential bodily systems such as those necessary for digestion, repair and rest. For this reason, heightened levels of cortisol and adrenaline can wreak havoc in the body over an extended period.

Effects of Stress

In the early stages of adrenal fatigue cortisol levels are high and this can have a number of negative health effects, especially when prolonged.

  • Immune function: both short and long-term stress can suppress the immune response(11).
  • Bone health: elevated levels of cortisol can disrupt the healthy rebuilding of bone(12).
  • Muscles and joints: erratic adrenal rhythms disrupt the healing of tissues(13).
  • Sleep: mean cortisol levels are elevated in sleep-deprived individuals(14). People with insomnia display increases in evening cortisol output which can affect the first nocturnal sleep period(15).
  • Fertility: the pituitary signals responsible for egg release each month are altered by stress(16), while testosterone levels and sperm production are also affected in men(17). Furthermore, prolonged stress can result in the ‘pregnenolone or cortisol steal’. Pregnenolone is a precursor hormone required to make both sex and stress hormones in the body. Under conditions of chronic stress, the body will prioritise the production of cortisol at the expense of DHEA, thus limiting the production of sex hormones such as oestrogen, progesterone and testosterone.
  • Thyroid function: cellular cortisol levels regulate the production of thyroid hormone. Stress hormones can affect the enzymes which convert T4 to T3 and may result in more T3 being converted into its inactive form, reverse T3(18). Cytokines or inflammatory immune cells released as part of the stress response can also make thyroid receptors less sensitive to thyroid hormones(19).
  • Memory: chronic stress decreases hippocampal function, the area in the brain responsible for memory formation(20,21).
  • Depression: several studies discovered a hyperactive HPA axis in patients with depression(22).
  • Glycaemic regulation: high cortisol can contribute to raised blood sugar, insulin resistance and obesity(23).

Is adrenal fatigue a real condition?

Currently Addison’s disease is the only medically recognised condition associated with adrenal insufficiency. To receive a diagnosis, over 90% of adrenal function must be lost. In the absence of this, endocrine function is deemed to be normal.

This has been challenged by naturopathic and integrative practitioners who use the term ‘adrenal fatigue’ to describe another condition; the point between Addison’s disease and optimal adrenal health. First described in 1998 by Dr. James L. Wilson, adrenal fatigue is a mild form of adrenal insufficiency which can occur following periods of prolonged stress. He hypothesised that during extended periods of stress, the overstimulation of the adrenal glands could lead to erratic blood cortisol levels, leaving the body with either too much or too little, as well as deviations in DHEA output(7).

The major challenge faced in creating diagnostic criteria for adrenal fatigue, as well as the primary cause for controversy, lies in the fact that many of the parameters for this condition are non-specific. In 2016, a systematic review concluded that there was a lack of scientific basis for claiming adrenal impairment as a cause of fatigue(24). While many commended this work, it also received significant criticism for the limitations of its methods, as numerous different biomarkers and questionnaires used to identify adrenal fatigue were accepted for review. What this paper did highlight however, is a need for further analysis of the methods required to accurately test the reality of a condition such as adrenal fatigue. Many clinicians agree that a diagnosis for adrenal fatigue is challenging as often cortisol levels will be within ranges considered to be ‘normal’ in conventional medical standards, while patients may still present with many of the associated symptoms. For this reason, a combination of testing and clinical feedback may be best to assess the likelihood of adrenal fatigue.

Interventions for the support of adrenal health

There are a number of nutrition and lifestyle interventions which may support adrenal health.


An anti-inflammatory diet consisting of unprocessed, wholefoods may be beneficial. Some foods have a negative impact on adrenal health and are best avoided completely. In addition, food allergens or intolerances should be considered.

Caffeine: this stimulant can interfere with the sleep cycle, making it difficult for the adrenals to recover and regenerate(25).

Protein: too much protein may impact cortisol levels(26,27) and so moderate protein consumption may be more appropriate when supporting adrenal fatigue. ­Where possible, choose organic.

Fat: processed and hydrogenated oils such as corn, sunflower and vegetable oil are highly inflammatory(28). Instead choose only high-quality sources such as avocado, olives, nuts, seeds, wild-caught oily fish and extra virgin olive oil.

Sugar and Carbohydrates: Not only is sugar highly inflammatory, but it can contribute to feelings of anxiety. Glycaemic regulation is closely linked to adrenal health(29). Focus on high fibre starchy vegetables as the main carbohydrate source, e.g. sweet potatoes, carrots, beets, as this will support stable blood sugar levels which can be difficult when consuming simpler carbohydrate forms such as rice, pasta and bread. Artificial sweeteners should also be avoided, with the use of natural sweeteners such as honey, dates and maple syrup in moderation.

Increase sleep

The average adult should be achieving between 7-8 hours of good quality sleep per night(30,31). Those experiencing adrenal fatigue, may require even more.

Maintain a routine

While seeking to support adrenal health, it is important to maintain consistent sleep and wake patterns in order to support the body in re-establishing a healthy sleep-wake cortisol cycle(32). Implementing consistent mealtimes may also have a positive impact on the circadian system(33).


Specific nutrients that may be considered include:

  • B vitamins: large quantities of vitamins B3, B5 and B6 are used in adrenal hormone production. Vitamin B3 is required to support the NADP-NADPH enzymes critical to the adrenal cascade, while vitamin B6 plays a role in the proper functioning of the HPA axis. Vitamin B5 is converted into acetyl-CoA which is vital for the conversion of glucose into energy and used up quickly in the adrenals during the production of hormones. While these B vitamins are particularly important, all of the B vitamins are required for energy production; they also act as cofactors for the multiple enzymatic reactions within the adrenals(34).
  • Vitamin C: the adrenals require more vitamin C than any other organ or tissue(35) and this requirement is increased while under stress(36). Bioflavonoids may be useful in enhancing the absorption of vitamin C(37).
  • Vitamin D: found to impact conditions such as adrenal dysfunction and disease(38).
  • Magnesium: this mineral is an essential cofactor to the enzyme and energy creation required for normal adrenal function. Furthermore, magnesium aids relaxation and supports sleep pathways which are often disrupted in individuals with adrenal fatigue(39,40).
  • Selenium: deficiency of selenium may negatively impact adrenal function(41).
  • Adaptogens: several studies indicate that adaptogenic herbs such as ashwagandha and ginseng work to normalise cortisol levels and mediate stress responses within the body(42,43). A study of chronically stressed patients demonstrated significant reductions in scores on all stress assessment scales and serum cortisol levels following supplementation with 300mg of ashwagandha root extract twice daily(44). Siberian ginseng resulted in an increase in mental performance and endurance among patients with weakness and mild fatigue(45).
  • Liquorice: the liquorice root spice has demonstrated an ability to increase DHEA, while preventing the body from using up its stores of cortisol(46).
  • Omega 3: an EPA and DHA rich omega supplement such as high-quality fish or algae oil may counteract many of the symptoms associated with adrenal fatigue such as anxiety, low mood and immune dysfunction(47,48).
  • Co-enzyme Q10 is a vital part of all energy production (i.e. ATP) in the mitochondria
  • D-ribose: a naturally-occurring sugar that is vital for energy production in our body. D-ribose is the main building block of ATP.

Key takeaways

  • Adrenal fatigue is a term used by naturopathic and integrative practitioners to describe a mild form of adrenal insufficiency in which the adrenals struggle to maintain output of key steroid hormones such as cortisol and DHEA while under prolonged stress.
  • Symptoms of adrenal fatigue include: prolonged or excessive tiredness, difficulty waking in the morning or falling asleep at night, inability to handle stress, dependency on stimulants to get through the day and strong salt and/or sugar cravings.
  • Adrenal fatigue may cause knock-on effects to thyroid health, mood and memory, glycaemic regulation, muscles and joints, bone health, fertility, sleep and immune function.
  • There are still no official diagnostic criteria available for adrenal fatigue, however a combination of laboratory testing and patient feedback are often used to assess the likelihood of this condition.
  • Dietary and lifestyle adjustments which support adrenal health include eating a balanced anti-inflammatory diet, getting plenty of quality rest, maintaining a routine, using adaptogenic herbs such as ashwagandha or ginseng and ensuring adequate micronutrient levels; especially B vitamins, vitamins C and D, magnesium and selenium.

If you have any questions regarding the topics that have been raised, or any other health matters please do contact me (Tracey) by phone or email at any time., 01684 310099

Tracey Hanley and the Cytoplan Editorial Team

Relevant Cytoplan products:

  • CoQ10 Multi an all-encompassing multivitamin and mineral formula including good levels of B vitamins and CoQ10 as ubiquinol
  • Adrenal Support herb complex containing Siberian ginseng, liquorice as well as vitamin B5, kelp (providing iodine), chromium and selenium.
  • Organic Ashwagandha used in traditional Ayurvedic medicine, it contains 500mg of organic Ashwagandha per capsule.
  • Siberian Ginseng an old medicinal plant which grows wild in the far east of Russia. This is considered to be a gentler form of ginseng to Korean ginseng. Each tablet contains 600mg of Siberian ginseng.
  • Vitamin B5 beneficially combined in a food base of inactive Lactobacillus bulgaricus in which it naturally occurs. Pantothenic acid helps to maintain a healthy digestive tract and can improve the body’s ability to withstand stressful conditions. Available in 50mg capsules.
  • Krill oil the most bioeffective natural source of beneficial omega 3 fatty acids EPA and DHA. Our formula also includes the powerful antioxidant astaxanthin and choline used in neurotransmitter synthesis. Two capsules contain 1,000mg of krill oil with 150mg EPA and 90mg DHA.
  • L-theanine an amino acid found in tea leaves and used to support relaxation, memory and sleep quality. Contains 250mg of L-theanine per capsule.
  • Biofood Magnesium Food State formulation which contains 100mg of elemental magnesium per tablet.
  • D-ribose – a naturally-occurring sugar that is vital for energy production in our body.

References available upon request. 


2 thoughts on “Could tired adrenals be the cause of your fatigue?

  1. Great article and very important area to explore. A comment on the term “adrenal fatigue” is that it suggests the adrenals are failing to produce hormones which may not be the case – they may be produced OK but released in a discordant manner. For this reason the much less memorable but likely more accurate term Hypothalamic Pituitary Adrenal Axis Dysfunction (HPA Axis Dysfunction) is a better descriptor. It is also the term used in conventional medical research and allows everyone to “speak the same language”.

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