"Adrenal fatigue" appears in a great many supplement listings, including from brands that ought to know better. We are going to give you the awkward answer rather than the convenient one.
The short version
The symptoms are real. The diagnosis is not recognised.
Adrenal fatigue is not accepted as a medical condition by endocrinology bodies, and systematic reviews of the available studies have not found evidence supporting it. There is no validated test for it and no agreed definition.
That does not mean people describing it are imagining anything. Exhaustion that does not lift, poor stress tolerance, waking unrefreshed — these are real experiences with real causes. The problem is that this particular label points away from finding them.
The theory, and where it breaks
The idea is that prolonged stress "exhausts" your adrenal glands until they can no longer produce enough cortisol, leaving you depleted.
It is intuitive, which is a large part of its appeal. The difficulty is that adrenal function does not appear to work that way. Studies looking for the pattern this theory predicts have not consistently found it, and the symptoms attributed to adrenal fatigue — tiredness, poor sleep, low mood, difficulty concentrating — are so non-specific that they fit dozens of conditions.
Which is precisely the danger.
Adrenal insufficiency is real, and serious
This is the crucial distinction.
Adrenal insufficiency, including Addison's disease, is a genuine endocrine condition in which the adrenal glands genuinely do not produce enough cortisol. It is diagnosed with specific testing — morning cortisol and, where indicated, an ACTH stimulation test — and it is treated with hormone replacement.
It is also potentially life-threatening. An adrenal crisis is a medical emergency.
Symptoms can include persistent fatigue, weight loss, low blood pressure, dizziness on standing, nausea, salt cravings and darkening of the skin. If those describe you, that is a GP appointment, not a supplement.
The reason this matters: someone who accepts an "adrenal fatigue" label from a supplement seller may spend a year on herbal blends while a real, treatable condition goes undiagnosed.
About the saliva cortisol tests
Salivary cortisol panels are widely sold to diagnose adrenal fatigue. They are not a validated diagnostic tool for it — you cannot validate a test for a condition with no agreed definition. Cortisol also varies substantially through the day and between days, which makes interpretation of a small number of samples unreliable.
If genuine adrenal insufficiency is suspected, the testing pathway is a medical one.
So what is actually causing it?
The symptom list attributed to adrenal fatigue overlaps almost entirely with things that can be identified and treated:
- Iron deficiency, B12 deficiency, thyroid dysfunction
- Sleep apnoea and poor sleep quality
- Depression and anxiety
- Perimenopause
- Post-viral fatigue, including long COVID
- ME/CFS
- Genuine adrenal insufficiency
- Sustained psychological stress — exhausting in its own right, without needing a gland to be broken
Every one is worth more of your time than the label. Start with what blood tests to ask for, and if those come back clear, what to look at next.
Where adaptogens honestly fit
We sell maca root and ashwagandha drops, and adaptogens are the category most often sold for "adrenal fatigue". So we should be straight about this.
Ashwagandha has research interest around the stress response and cortisol. That is not the same as treating a condition that is not recognised, and we are not going to present it that way. If you are under sustained stress and want to support how you handle it, that is a reasonable and honest reason to try an adaptogen — alongside sleep, movement and, where relevant, actual help with the stressor.
Ashwagandha is also not for everyone: it is generally avoided in pregnancy and needs medical advice if you have a thyroid condition or take sedatives. That is on the product page too. See maca vs ashwagandha for which one suits which situation.
Questions people ask
Why do so many brands sell adrenal fatigue supplements?
Because the symptoms are common, the label is intuitive, and it is easier to sell a bottle than to say "see your GP". We would rather not be one of them.
My naturopath diagnosed me with it — are they wrong?
Your exhaustion is real and worth taking seriously. What we would encourage is also seeing a GP and getting the standard bloods done, so anything treatable is not missed while you work on the rest.
Does that mean stress does not affect my body?
Not at all. Chronic stress has well-documented effects on sleep, appetite, immune function and mood. The disputed claim is the specific mechanism — that stress exhausts your adrenal glands into underproduction.
Who wrote this, and why
Written by Daniel, founder of Nutritions Lab. We are a retailer, not a clinic — nobody here is a doctor or endocrinologist.
We could sell more adaptogens by using the phrase "adrenal fatigue" the way most of this industry does. We have chosen not to, for the same reason we published an honest article about soursop and cancer claims: if the honest answer reduces the appeal of something we stock, the honest answer still gets published.
Our approach is set out in our editorial policy. If you believe we have this wrong, tell us — we will look at it properly.
General information only, not medical advice. If you have symptoms of adrenal insufficiency — persistent fatigue with weight loss, dizziness, low blood pressure or skin darkening — please see a doctor rather than a supplement retailer.
