You wake up tired, even after a full night’s sleep. Getting out of bed feels like wading through wet sand, and by mid-morning you’re lightheaded if you stand up too fast. You crave salty food for no obvious reason, your blood pressure runs low, and some afternoons you feel like you could lie down on the office floor.
You mentioned it to your GP. They ran a blood panel. It came back “normal.”
Here’s the problem: a standard blood test rarely looks for low cortisol, and if your adrenal glands aren’t producing enough of it, you can feel this way every single day while your paperwork says you’re fine. Low cortisol is a real, measurable hormonal pattern, and it explains a lot of symptoms that get dismissed as stress, ageing, or “just being busy.”
What Cortisol Actually Does
Cortisol is your main stress hormone, made by your adrenal glands. It follows a daily rhythm called the circadian pattern.
In a healthy system, cortisol rises sharply when you wake to give you energy for the day. It then tapers off through the afternoon and evening, dropping to its lowest point around midnight so you can sleep deeply.
Cortisol naturally rises with stress and follows this daily rhythm, and producing too much or too little can lead to health problems. Beyond the stress response, this hormone also:
- Regulates blood sugar and metabolism
- Controls inflammation
- Supports immune function
- Manages blood pressure
- Influences mood and concentration
- Affects how well your thyroid hormone converts and works
When your adrenal glands can’t keep up with the demand, this whole system starts to slip.
What Is Low Cortisol?
Low cortisol, also called hypocortisolism or adrenal insufficiency, happens when your adrenal glands don’t produce enough cortisol to meet your body’s needs. It can develop gradually after long periods of high stress, or it can stem from autoimmune damage to the adrenal or pituitary glands.
This is not the same as simply “being tired.” Low cortisol changes how your body regulates blood sugar, blood pressure, and your response to everyday physical demands.
Symptoms of Low Cortisol
Low cortisol rarely shows up as one clear symptom. It tends to arrive as a cluster that’s easy to explain away individually but hard to ignore together.
- Unrelenting fatigue that rest doesn’t fix. You can sleep nine hours and still wake up drained, because your body lacks the hormone that’s meant to energise you.
- Dizziness or lightheadedness on standing. Cortisol helps regulate blood pressure, so low levels often mean your blood pressure drops when you change position.
- Salt cravings. Cortisol helps your body hold onto sodium, so a shortage can trigger a genuine physical craving for salty food.
- Low blood pressure. This is a direct downstream effect of insufficient cortisol.
- Sugar cravings or shakiness between meals. Cortisol helps keep blood sugar steady, so low levels can cause it to dip.
- Unexplained weight loss. Unlike high cortisol, which tends to add weight, low cortisol often takes it off.
- Low mood, flatness, or loss of motivation. This isn’t the anxious, wired feeling of high cortisol. It’s closer to running on empty.
- Muscle or joint pain, along with nausea or digestive upset. Widespread, chronic pain like this often travels with fibromyalgia and adrenal burnout, so it’s worth ruling that in or out too.
Adrenal insufficiency can cause severe fatigue, dizziness on standing, salt cravings, low blood pressure, unexplained weight loss, and digestive problems, and it’s frequently mistaken for burnout rather than picked up as a hormonal issue that needs testing.
What Causes Low Cortisol?
A few different patterns can lead to low cortisol, and they don’t all involve the same level of medical urgency.
- Prolonged, unmanaged stress. Sustained high demand on your stress-response system can eventually wear it down.
- Autoimmune adrenal damage (Addison disease). Your immune system attacks the adrenal glands directly.
- Pituitary gland dysfunction. Your pituitary gland tells your adrenals how much cortisol to make. If that signal breaks down, output drops too.
- Stopping long-term steroid medication too quickly. This can suppress your body’s own cortisol production temporarily.
- Traumatic brain injury or chronic illness, both of which can disrupt the hypothalamic-pituitary-adrenal axis that governs cortisol output.
You’re Not the Only One Feeling This
Adrenal insufficiency admissions across Australian hospitals rose 62% between 2000 and 2019, while admissions for adrenal crisis rose 90% over the same period. Women had higher admission rates than men throughout, with increases recorded across every female age group, while men only showed an increase in their 70s.
If you’re a woman in your 30s, 40s, or 50s who feels constantly drained, dizzy on standing, or unable to keep up no matter how much you rest, you sit right inside the group these hospital figures show climbing the fastest. This isn’t a rare, unusual thing happening to you alone.
More than two in five Australians will experience a mental health condition at some point in their life, and about one in five are living with one right now. Chronic stress at that scale is one of the most common drivers of adrenal exhaustion, so if ongoing stress is part of your story, you’re far from alone in it.
The Thyroid Connection
Cortisol and thyroid function are tangled together more closely than most people realise. Chronic stress pushes your body to prioritise cortisol production, sometimes at the expense of the hormones your thyroid and reproductive system rely on, a pattern known as “pregnenolone steal.”
About 40% of Australian women have an undiagnosed thyroid problem affecting how they feel, and thyroid dysfunction and low cortisol frequently show up together. If one system is under strain, it’s common for the other to be quietly struggling too, which is why we test both rather than one in isolation. Brain fog, exhaustion, and mood changes that won’t lift often trace back to this same thyroid-adrenal burnout pattern.
Low Cortisol vs High Cortisol: Telling Them Apart
High and low cortisol can produce overlapping symptoms, including fatigue and weight changes, which is exactly why guessing doesn’t work.
Symptom area | Low cortisol | High cortisol |
Energy | Profound exhaustion that doesn’t lift | Wired, restless, hard to wind down |
Weight | Often unexplained weight loss | Often weight gain, especially around the middle |
Blood pressure | Low, with dizziness on standing | Elevated |
Mood | Flat, low motivation, low mood | Anxious, agitated, racing thoughts |
Sleep | Sleeping enough but still drained | Trouble falling asleep, tired but wired |
If that sounds more like you, racing thoughts, stubborn weight around the middle, feeling wired even at midnight, that’s high cortisol, not low. You don’t have to guess which one it is. Get your signs of adrenal stress properly tested and know for sure.
How We Test for Low Cortisol
Guessing which type of cortisol imbalance you have, or whether it’s cortisol at all, can lead to the wrong intervention. Testing removes that guesswork.
Our Stress & Sleep Profile measures your salivary cortisol at three points across the day, alongside melatonin and DHEA. This is not a blood test. It’s an at-home kit, mailed directly to you, which you use to collect saliva samples at set times and post back for analysis at our in-house lab.
Timing is the key here, because cortisol should follow a specific daily curve. A single blood draw only captures one moment, but sampling morning, midday, and evening reveals whether your levels are low across the board or dropping at the wrong point in the day.
We often pair this with our Thyroid Profile, a fasting blood test collected at any Healius network pathology centre, since low cortisol and thyroid dysfunction so often travel together. Wondering why saliva and not a blood draw? Our cortisol blood test vs saliva test breakdown explains why timing beats a single number every time.
Treatment Options for Low Cortisol
Treatment depends on how depleted your cortisol is and what’s driving it. Some cases need medical management, others respond well to rebuilding the body’s own capacity, and many benefit from both working together.
Medical Approaches
For diagnosed adrenal insufficiency, particularly Addison disease, hydrocortisone replacement therapy prescribed by an endocrinologist is the standard medical treatment. GPs and endocrinologists are well equipped to identify and manage the more severe end of this spectrum, and we respect that. We work alongside it, not instead of it.
Integrative Approaches
For the more common pattern of adrenal strain from prolonged stress, we focus on rebuilding capacity rather than masking symptoms.
- Targeted nutrients, including vitamin C, B vitamins, and magnesium, to support adrenal function.
- Adaptogenic herbs, such as liquorice root and Rhodiola, chosen specifically for their cortisol-supporting effect.
- Regular, balanced meals to prevent the blood sugar crashes that add extra strain to an already depleted system.
- Adequate salt and fluid intake where blood pressure is running low.
- Rest genuinely prioritised, not just recommended, alongside a realistic plan for reducing the load causing the depletion in the first place.
Information supplied is for educational purposes only and not intended to diagnose or treat a condition. Refer to your medical professional.
Ready to Find Out What’s Really Going On?
If your bloods look “normal” but you still feel exhausted, dizzy, or like your body is running on empty, that gap between the paperwork and how you feel is worth investigating properly. Guessing whether it’s stress, thyroid, or something else rarely fixes it.
At The Lucy Rose Clinic, we run the Stress & Sleep Profile alongside thyroid and nutrient testing so you get a complete picture, not a single data point. From there, we build a plan around what your results show, not a generic supplement list.
Book a free 15-minute consultation with one of our naturopaths. We’ll go through your symptoms, explain which tests make sense for what you’re experiencing, and map out what a clear plan looks like from there. No pressure, no obligation.
Frequently Asked Questions
The most common signs are unrelenting fatigue, dizziness on standing, salt cravings, low blood pressure, and unexplained weight loss. Low mood and digestive upset can also appear alongside these.
Low cortisol can follow prolonged unmanaged stress, autoimmune damage to the adrenal glands, pituitary gland dysfunction, or stopping long-term steroid medication too abruptly. Chronic illness and traumatic brain injury can also disrupt cortisol production.
The most informative approach measures salivary cortisol at several points across the day rather than a single blood draw, since cortisol should follow a specific daily rhythm. At The Lucy Rose Clinic, this is done through an at-home saliva kit alongside a fasting thyroid blood test.
“Adrenal fatigue” is a lay term people use to describe the pattern of prolonged stress leading to depleted cortisol output. Low cortisol and adrenal insufficiency are the clinical terms, ranging from mild depletion through to diagnosed conditions like Addison disease.