Last updated: October 2026
Adrenal fatigue isn’t a recognised medical condition. The idea is that long-term stress wears out your adrenal glands, but a 2016 systematic review of 58 studies found no evidence for it, and there’s no valid test. The tiredness is real, though, so see a GP to check for causes such as anaemia, thyroid problems or depression.
Below: what adrenal fatigue is supposed to be, the symptoms people describe, what the evidence says, saliva tests vs NHS tests, how it differs from Addison’s disease and burnout, the real causes of tiredness worth checking, and what actually helps.
The short version: your exhaustion is real, but “adrenal fatigue” is the wrong label for it. Endocrinologists say your adrenal glands don’t “run out” from stress. The risk is that a made-up diagnosis, and the pricey supplements sold with it, delays you finding the real, treatable cause.
What is adrenal fatigue?
Your adrenal glands sit on top of your kidneys. They make hormones including cortisol, which helps control your stress response, blood pressure and blood sugar, and aldosterone, which helps balance salt and water.
The adrenal fatigue theory says that months or years of stress force the adrenals to pump out cortisol until they become “exhausted” and can’t keep up. Supporters say this leaves you tired, foggy and craving salt or sugar, and that it can be found with a saliva test and fixed with supplements.
It’s an appealing story, because stress and exhaustion often do go together. The problem is that the middle step, glands wearing out from everyday stress, has never been shown to happen. For how cortisol really behaves under stress, see high cortisol symptoms and how to lower cortisol naturally.
Adrenal fatigue symptoms (as usually described)
Websites and clinics that sell adrenal fatigue testing usually list symptoms like these:
- tiredness that sleep doesn’t fix, and trouble getting up in the morning
- an afternoon slump, then feeling “wired but tired” at night
- relying on caffeine or sugar to get through the day
- brain fog and poor concentration
- low mood, irritability or feeling overwhelmed
- salt cravings, dizziness on standing, aches and frequent colds
Every one of these is real and worth taking seriously. But they’re also very common, and they overlap with dozens of conditions, from iron deficiency and an underactive thyroid to depression, poor sleep and ongoing stress. That’s exactly why a vague label is risky: it fits almost everyone who feels run down.
Some of these symptoms, especially salt cravings, dizziness on standing, weight loss and darker patches of skin, are also signs of Addison’s disease, a real adrenal condition (see below). If you have those, see a GP rather than buying a test online.
Is adrenal fatigue real? What the evidence says
No, not as a medical condition. The clearest evidence comes from a 2016 systematic review by two Brazilian endocrinologists, Cadegiani and Kater. They screened 3,470 papers and analysed the 58 studies that measured cortisol alongside fatigue or energy levels.
The results were inconsistent from study to study, whatever test was used, and the authors concluded there was no substantiation that adrenal fatigue is an actual medical condition. In their words, it is “still a myth”.
The Endocrine Society, the international body for hormone doctors, says the same: no scientific proof supports adrenal fatigue as a true medical condition. Its main worry is practical. A false diagnosis can mean the real reason you feel unwell gets missed.
None of this means you’re imagining things. Long-term stress does affect sleep, mood, appetite and energy. It just doesn’t do it by wearing out your adrenal glands, and the fix is usually to find and treat the actual cause.
Adrenal fatigue tests: saliva kits vs NHS testing
You can buy “adrenal stress” or cortisol saliva kits online, usually with four samples across a day. The Endocrine Society says there’s no test that can detect adrenal fatigue, and that these tests aren’t based on scientific facts, so the results can be unreliable. Cortisol naturally rises and falls through the day and shifts with sleep, stress, illness, caffeine and some medicines, so a few readings can easily look “abnormal” in a healthy person.
| Online saliva “adrenal fatigue” kits | NHS adrenal testing | |
|---|---|---|
| What it looks for | “Adrenal fatigue”, which isn’t a recognised condition | Real adrenal disease, such as Addison’s disease |
| How it’s done | Saliva samples at home, posted to a private lab | Blood tests, then a specialist (endocrinologist) may do a Synacthen test, comparing blood before and after an injection |
| Who interprets it | Often the company selling the supplements | Your GP and hospital specialist |
| Cost | Paid privately | Free on the NHS when your GP thinks it’s needed |
| What it can tell you | Little that’s reliable for diagnosis | Whether your adrenal glands are working properly, plus checks such as thyroid function |
If you’re worried about your adrenals, the better first step is a GP appointment. Tell them about all your symptoms, how long you’ve had them and any steroid medicines you take, including inhalers, creams and injections.
Adrenal fatigue vs adrenal insufficiency (Addison’s disease)
Adrenal insufficiency is real and can be serious. In Addison’s disease, the adrenal glands are damaged, most often by the immune system attacking them by mistake, and can’t make enough cortisol and aldosterone.
The NHS lists symptoms including extreme tiredness, darker patches of skin, loss of appetite, weight loss, tummy pain, feeling or being sick, salt cravings, dizziness when standing up, muscle and joint aches, excessive thirst and low mood. It’s diagnosed with blood tests and treated with daily steroid hormone replacement, usually for life.
Call 999 if someone has symptoms of an adrenal crisis: a fast heart rate, severe dizziness, severe pain in the tummy or side, muscle weakness or spasms, a persistent headache, being sick, drowsiness or confusion, a seizure or loss of consciousness. The NHS says to call 999 even if an emergency steroid injection has been given.
| “Adrenal fatigue” | Adrenal insufficiency (Addison’s) | |
|---|---|---|
| Recognised by doctors? | No | Yes |
| Cause | Said to be long-term stress | Damaged adrenal glands, often autoimmune |
| Test | None valid | Blood tests and a Synacthen test |
| Treatment | Supplements, with no proven benefit | Prescribed steroid replacement |
| Can it be an emergency? | No | Yes: adrenal crisis |
One more reason not to self-treat: the Endocrine Society warns that taking adrenal hormones you don’t need can make your own adrenal glands stop working, which can lead to an adrenal crisis.
Adrenal fatigue vs burnout
Many people who search for adrenal fatigue are really describing burnout. The World Health Organization includes burnout in ICD-11 as an occupational phenomenon, not a medical condition. It describes it as a syndrome from chronic workplace stress that hasn’t been successfully managed, with three parts:
- feeling drained or exhausted
- growing mental distance from your job, or feeling negative and cynical about it
- getting less done, or feeling less effective at work
The key difference is that burnout describes how chronic stress affects you, without claiming your glands have failed. It points you towards the right fixes: workload, rest, boundaries and support. Our guide to burnout symptoms, stages and recovery goes into detail.
Real causes of tiredness to check with a GP
The NHS lists many causes of feeling tired all the time, including poor sleep, stress, depression, hormonal changes such as the menopause, illnesses, medicines, and conditions such as sleep apnoea, iron deficiency anaemia, diabetes and thyroid problems. Its advice is clear: don’t self-diagnose.
| Possible cause | Other clues | Read more |
|---|---|---|
| Iron deficiency anaemia | Pale skin, shortness of breath, heart palpitations | Iron deficiency symptoms |
| Underactive thyroid | Feeling cold, weight gain, constipation, dry skin or hair | Underactive thyroid |
| Vitamin B12 deficiency | Pins and needles, a sore or red tongue, memory problems | B12 deficiency |
| Low vitamin D | Worth asking about if you get little sun, especially from October to March | Vitamin D deficiency |
| Sleep apnoea | Loud snoring, gasping or choking noises in your sleep, headaches on waking | Why do I wake up tired? |
| Depression or anxiety | Low mood, worry, losing interest in things | See a GP |
| Perimenopause | The NHS lists hormonal changes, including the menopause, as a cause of tiredness | Perimenopause symptoms |
| Not enough sleep | Short or broken nights, relying on caffeine | Sleep deprivation |
A simple set of blood tests rules many of these in or out. For a fuller list, see why am I always tired?
Adrenal fatigue supplements and treatment: what to know
As adrenal fatigue isn’t a recognised condition, there’s no proven treatment for it. That hasn’t stopped a large market in “adrenal support” products, and some carry real risks.
In 2018, endocrinologists at the Mayo Clinic tested 12 over-the-counter adrenal support supplements bought in the US. Every one contained a small amount of thyroid hormone (T3), and most contained at least one steroid hormone. A quarter contained budesonide, a steroid used in medicines, and some contained cortisol itself. The authors warned of the potential risks of hidden ingredients in unregulated supplements.
Hidden hormones matter. The Endocrine Society warns that taking adrenal hormones you don’t need can make your own adrenal glands stop working. It also notes there’s no guarantee that what’s on a supplement label is really what’s inside. Be especially wary of “adrenal glandular” products, which can be made from animal glands.
If you want a supplement for tiredness, choose one with an authorised claim from a brand that shares its lab reports. Our best supplements for energy, ranked by evidence guide explains which nutrients have authorised claims, and adaptogens for energy looks honestly at herbs like ashwagandha and rhodiola, which have research but no authorised claims.
What actually helps when you feel exhausted
- Get checked. If tiredness has lasted a few weeks with no obvious reason, see your GP.
- Protect your sleep. The NHS suggests regular sleep times and aiming for 6 to 9 hours, plus a dark, quiet, cool bedroom.
- Wind down. Relax for a couple of hours before bed and avoid screens in the last hour.
- Watch the caffeine. Avoid caffeine, big meals and hard exercise close to bedtime.
- Eat regularly and move daily. A healthy diet and regular exercise are the NHS’s first suggestions for tiredness. See how to boost energy naturally.
- Cut back on alcohol and stop smoking. Both make tiredness worse.
- Deal with the stress itself. Workload, boundaries, talking to someone, and time outdoors all count.
If your diet is low in magnesium, it’s one nutrient with an authorised claim here: magnesium contributes to the reduction of tiredness and fatigue. Our Magnesium Glycinate Sleep Complex is a caffeine-free evening drink with 148mg of magnesium per serving, and our Reishi Mushroom Adaptogenic Complex is a reishi hot chocolate for a calmer evening ritual. Neither is a treatment for any condition, and neither replaces a GP check. More on the mineral in magnesium for energy.
When to see a GP
See a GP if you’ve felt tired for a few weeks and don’t know why, if tiredness is affecting your daily life, or if you also have weight loss, mood changes, or you’ve been told you gasp, snort or choke in your sleep.
Get help sooner if you have signs that could point to Addison’s disease, such as salt cravings, dizziness when standing, weight loss, being sick or darker patches of skin. Call 999 for signs of an adrenal crisis. If you take steroid medicine, don’t stop it suddenly without medical advice.
FAQs
Is adrenal fatigue real?
No, not as a medical condition. A 2016 systematic review of 58 studies found no evidence for it, and the Endocrine Society says there is no scientific proof it exists. The tiredness people feel is real, so it’s worth finding the actual cause with a GP.
What are the symptoms of adrenal fatigue?
People usually describe tiredness that sleep doesn’t fix, brain fog, low mood, relying on caffeine and salt or sugar cravings. These symptoms are common to many conditions, including anaemia, thyroid problems, depression and poor sleep.
Can the NHS test for adrenal fatigue?
No, because it isn’t a recognised condition. The NHS can test for real adrenal problems such as Addison’s disease, using blood tests and a Synacthen test, and can check common causes of tiredness with blood tests.
Are saliva cortisol tests accurate for adrenal fatigue?
The Endocrine Society says adrenal fatigue tests aren’t based on scientific facts and their results can be unreliable. Cortisol naturally changes through the day and with sleep, stress and caffeine.
What is the difference between adrenal fatigue and Addison’s disease?
Addison’s disease is a real condition where damaged adrenal glands can’t make enough hormones. It’s diagnosed with blood tests and treated with steroid replacement, and it can cause a life-threatening adrenal crisis. Adrenal fatigue is not a recognised diagnosis.
Are adrenal support supplements safe?
Some may not be. A 2018 study of 12 adrenal support supplements found all contained thyroid hormone and most contained at least one steroid hormone. Speak to a GP or pharmacist before taking them, especially if you take other medicines.
Is adrenal fatigue the same as burnout?
No. Burnout is recognised by the WHO as an occupational phenomenon caused by chronic work stress that hasn’t been managed. It describes exhaustion and detachment from work without claiming the adrenal glands have worn out.
Sources
- Cadegiani FA, Kater CE. Adrenal fatigue does not exist: a systematic review. BMC Endocr Disord. 2016;16(1):48. PMID 27557747.
- Akturk HK, et al. Over-the-counter “adrenal support” supplements contain thyroid and steroid-based adrenal hormones. Mayo Clin Proc. 2018;93(3):284-290. PMID 29502560.
- Endocrine Society. Adrenal fatigue.
- NHS. Addison’s disease.
- NHS. Tiredness and fatigue
- World Health Organization. Burn-out an “occupational phenomenon”: International Classification of Diseases.
This guide is general information, not medical advice. Evopure makes the Magnesium Glycinate Sleep Complex and Reishi Mushroom Adaptogenic Complex.
