What Does Cortisol Do? A Guide for Women

If you’ve scrolled through social media lately, you’ve likely been told there’s one particular hormone—cortisol—that’s behind your daily exhaustion, those extra pounds hanging around your belly, and your nightly habit of waking up at 3 a.m. But, well, what does cortisol do? Could it truly be at the root of all these issues—and if so, why are our bodies making this “demon” hormone? 

While viral videos about midlife cortisol aren’t always totally off-base, the online hype usually forgets to mention that this hormone actually has some pretty essential jobs in the body. 

To set the record straight, keep reading for a rundown of exactly what cortisol hormone is and what it does, how menopausal hormone changes affect it, what cortisol imbalance symptoms really look like, and whether testing is needed—plus what actually helps if your cortisol gets out of whack. We’ll also run through how a clinician trained in women’s health (like a Midi clinician) can help answer more questions and, when needed, help you find relief.

What Is Cortisol, and Where Does It Come From?

Cortisol is a hormone that gets produced by the adrenal glands, which sit right on top of your kidneys. It’s a glucocorticoid, a type of steroid hormone.

It’s known as the most famous of the stress hormones because that’s a big thing that triggers it: stress. This happens via a chain reaction called the hypothalamic-pituitary-adrenal (HPA) axis, as follows: 

• When your brain detects a stressor, the hypothalamus deep within the brain releases corticotrophin-releasing hormone. 
• This triggers the pituitary gland to release adrenocorticotropic hormone (ACTH). 
• And that signals your adrenal glands to release cortisol. 
• If everything’s working as it should, rising cortisol tells the hypothalamus and pituitary to dial back their signals, which brings the system back to baseline. 

You’re likely also familiar with adrenaline, another stress hormone. The difference is that while adrenaline offers a short burst of heart-pumping, muscle-tensing energy to escape immediate danger (like a bear that’s chasing you—or whatever’s causing you stress), cortisol is a slow burn that sticks around longer to keep that energy available (so you can fully outrun that bear). 

What Does Cortisol Do in the Body?

Cortisol plays a role in nearly every major organ system. Here’s a rundown of its biggest jobs: 

• Stress response: Cortisol activates your brain and body to better take on big challenges. It can also affect your mood and emotional regulation. 
• Metabolism: Cortisol raises your blood sugar levels and makes your cells less sensitive to insulin. When levels stay chronically high, it can increase your appetite and lead to fat storage, especially around the abdomen.
• Blood pressure: Cortisol regulates vascular tone (how constricted your blood vessels are). Chronically high cortisol can lead to high blood pressure, while low levels can cause low blood pressure.  
• Sleep-wake rhythm: Cortisol follows a daily rhythm—highest in the morning, which helps you feel alert, and lowest at night. 
• Immunity and inflammation: In the short term, cortisol helps calm inflammation. (In fact, corticosteroid medications, like prednisone and hydrocortisone, are synthetic versions of cortisol; they act on the same receptors as cortisol, which is why they’re powerhouses at reducing inflammation.) However, if you’re under chronic stress, immune cells become less responsive to cortisol, and you can end up with persistent inflammation. 

The Daily Cortisol Curve: When Is Cortisol Highest?

When cortisol is working the way it’s supposed to, it’s got a distinct daily curve. So, when is cortisol highest? Shortly after you wake up, cortisol levels peak to help mobilize your blood sugar and prep your body and mind for the day ahead. 

Levels gradually taper off throughout the afternoon and evening, then reach their lowest point late at night (usually around midnight). Then they start rising again 2 or 3 hours later, starting the cycle over. 

This means that you should feel awake and energized in the morning, then be able to wind down at night. But certain factors may mess with the curve: shift work, sleep loss, chronic stress, and having caffeine too late in the day, doing intense exercise too close to bedtime, and being exposed to bright light at night. A flattened cortisol curve—where natural daily fluctuations are reduced—can cause chronic fatigue and is linked to depression and systemic inflammation. An inverted curve flips your normal rhythm, leaving you groggy in the morning and wired at night.

What Happens When Cortisol Is Too High?

It’s normal for cortisol to rise in short bursts when you’re stressed. But when you’re stressed for weeks or months, your HPA axis can get out of syncdysregulated, which may throw off your cortisol rhythm and your body’s response to it. 

Some of the ways that chronic stress can show up:

• ongoing low-grade inflammation
• weight gain around the midsection
• insulin resistance and elevated blood sugar
• frantic middle-of-the-night wake-ups with racing thoughts
• brain fog
• mood shifts
• trouble focusing

“Your cortisol levels might rise, but that doesn’t mean there’s an abnormality,” says Midi clinician Heather Hofflich, DO, a board-certified endocrinologist and internist. 

A clinician will typically only evaluate your cortisol levels if you’re showing hallmark signs of a medical disorder that results from overly high cortisol levels called Cushing’s syndrome, Dr. Hofflich explains. Symptoms may include a rounded face, unusual weight gain in the abdomen, a fat pad at the base of the neck, easy bruising, and purple stretch marks.

What Happens When Cortisol Is Too Low?

Low cortisol is called adrenal insufficiency, and clinicians categorize it based on its specific cause: 

• Primary adrenal insufficiency: This is when the adrenal glands are damaged, most often because the immune system has attacked them (called Addison’s disease) or because of an infection or lack of blood to the adrenal glands. 
• Secondary or tertiary adrenal insufficiency: The adrenal glands are fine, but they’re not getting signals from your pituitary gland or hypothalamus. This can happen when you suddenly stop taking corticosteroids. 

Either way, you can end up feeling weak and dizzy, with low blood pressure and little appetite. 

Adrenal insufficiency symptoms can rapidly get worse and cause a lack of blood flow to your organs. Get emergency treatment if you experience:

• severe weakness
• dizziness, lightheadedness, fainting
• sudden, terrible pain in the low back, belly, or legs
• severe vomiting and diarrhea
• fever
• confusion

Although you may have heard of “adrenal fatigue” online, that’s not a real medical diagnosis. Chronic stress can’t “use up” all of your cortisol the way influencers might claim. That doesn’t mean your exhaustion isn’t real, though. If it’s interfering with your daily life, it deserves a proper workup to check for thyroid, iron, sleep, mood, or other issues.  

How Do Perimenopause and Menopause Change Cortisol?

Cortisol levels in women can look a little different once perimenopause and menopause roll around. Hormonal shifts during this transition, including changes in estrogen and progesterone, can affect the body’s stress response.

The result? In some women, cortisol might stay high overnight rather than dipping down to help you relax, according to a study in the journal Menopause. That rise appears to be linked to a mix of hormonal changes, not estrogen alone, and disrupted sleep may also play a role. This also doesn’t happen to everyone, Dr. Hofflich says. 

Meanwhile, perimenopausal hot flashes and night sweats can trigger middle-of-the-night cortisol spikes, causing sleep loss that disrupts your overall cortisol balance. Add in midlife pressures—like managing work, kids, and aging parents—and stress levels can quickly add up.

You might notice yourself feeling exhausted, trying to cope with anxiety and irritability, experiencing brain fog, and finding that fat is gradually settling around your waistline. But this is more likely due to shifting hormones than a serious cortisol problem. 

“While cortisol levels do rise due to the falling estrogen, it’s not enough to cause a disorder like Cushing’s syndrome,” Dr. Hofflich says. 

A healthcare professional, such as a Midi clinician, can help you figure out the true culprit behind your symptoms. 

How Is Cortisol Tested?

Cortisol levels can be tested in a few ways:

• Saliva test: People who want to get a better sense of how their cortisol rises and falls through the day can do a saliva test. It involves spitting in a tube at four distinct points during the day, starting right after waking. 
• Blood draw: This involves getting blood taken at a lab, and it’s used to diagnose Addison’s disease or Cushing’s syndrome. 
• Urine test: If a healthcare professional suspects Cushing’s syndrome, they might have a patient collect all the urine they make in a 24-hour period to measure how much cortisol they excrete. (Again: Cushing’s syndrome is rare.)

While at-home kits can give you a general idea of what’s going on, they can’t make a diagnosis. And because blood and urine cortisol tests are mainly used to diagnose adrenal disorders, Midi clinicians won’t order them—if they suspect an underlying adrenal disorder, they can refer you to an endocrinologist for further care. 

And remember, even if you take a cortisol test at home: A single test won’t tell the whole story, since the hormone naturally rises and falls every 24 hours (and even the stress of getting tested can artificially raise the number). 

What ‘Cortisol Detox’ and ‘Cortisol Belly’ Marketing Gets Wrong

You cannot “detox” from cortisol. Your body is constantly producing it—because you need it! The goal is not to eliminate cortisol from your body but to hit a healthy rhythm.  

And while cortisol belly is a real phenomenon, several factors beyond cortisol can impact weight gain in your midsection in midlife: the decline in estrogen, disrupted sleep, the muscle loss, and the natural metabolism slowdown that happens as we get older.

So, if an influencer is selling a cortisol detox or promising a quick fix to shrink your waist, be wary. Rather than taking a DIY approach, run any cortisol questions or concerns by a clinician— because incorrectly diagnosing yourself with a cortisol problem could potentially delay treatment you need for, say, a thyroid issue or sleep apnea. 

Evidence-Based Ways to Support Healthy Cortisol

Certain lifestyle changes can dramatically lower your stress levels: 

• Protect your sleep: Keep a consistent bedtime, make sure you’re exposed to sunlight in the morning, limit late caffeine and alcohol, and get treatment for night sweats and insomnia. 
• Move strategically: Exercise can lower cortisol levels, but consider skipping any intense activity in the hour before bed, since it could leave you wired. 
• Eat well: Focus on regular meals with protein and fiber to keep your blood sugar steady, and try to avoid cortisol-triggering foods (such as those that cause blood-sugar swings). 
• Recharge: Find the stress management tools that work best for you, whether that’s breathwork, finding time to meditate, spending time outside, hanging with friends, or doing therapy. 
• Ask about supplements: Certain adaptogenic botanicals like ashwagandha, L-theanine, and magnesium glycinate (all found in Midi’s Daily Cortisol Support) have research behind them to potentially help lower stress-related cortisol. 
• Get hormonal support: A clinician may recommend taking steps to ease perimenopause and menopause symptoms (like insomnia and night sweats) through menopausal hormone therapy. 

When to Talk With a Clinician About Cortisol

You’ve got your answer to “What does cortisol do?” Now, how do you decide whether your cortisol levels merit a conversation with a healthcare professional? 

It’s a good idea to bring up the issue if:

• You’re concerned about your daily stress. 
• You have Cushing’s symptoms (round face, easy bruising, fat pad at the base of the neck, purple stretch marks, unusual weight in the middle).
• You have adrenal insufficiency symptoms (weakness, dizziness, low blood pressure, little appetite).

A checkup will typically start with a symptom history, including any changes to your sleep patterns, mood, or menopause symptoms. From there, if needed,  your clinician will order targeted labs. 

A virtual visit with a Midi clinician—who will consider your hormones, sleep, stress, and metabolism together—can be a convenient and expert-informed way to get the answers you’re after. When needed, your clinician can also refer you to a specialist for further treatment. Getting personalized care will help you understand what’s going on with your cortisol and your health in general and get you what you need to feel better. (Plus, Midi’s virtual visits are in network with most major insurance plans nationwide.)

Key Takeaways

• Cortisol helps regulate your stress response, metabolism, blood pressure, sleep-wake cycle, and immune function. It impacts nearly every organ in the body. 
• Healthy cortisol levels naturally peak in the morning to energize you for the day, then dip at night. 
• True cortisol disorders are rare, but it’s possible to have clinically high cortisol (Cushing’s syndrome) or low cortisol (adrenal insufficiency).
• The menopausal transition can elevate cortisol, but it won’t cause a cortisol disorder on its own.  
• If lifestyle changes (like better sleep and regular exercise) don’t help you feel better about your cortisol levels, an expert trained in women’s health, like a Midi clinician, can help you get to the bottom of your symptoms. 

Frequently Asked Questions (FAQs)

How can you tell if your cortisol is out of whack?

Cortisol that’s off-rhythm (but not at the extreme of Cushing’s syndrome or adrenal insufficiency) doesn’t have a clear diagnosis, but it could potentially lead to fatigue, a low mood, trouble concentrating, or metabolism issues.

Is cortisol tested in routine blood work?

Cortisol is not tested in routine blood work. Targeted labs need to be ordered by a clinician—this would usually involve a blood draw or saliva test. A single test, though, isn’t particularly accurate because cortisol fluctuates.

Does coffee spike your cortisol?

Yes, caffeine can temporarily raise your cortisol levels. Though if you’re a regular coffee drinker, research suggests that they don’t increase quite as much after a cup. 

How do you prevent cortisol spikes at night?

Certain lifestyle habits—like keeping a consistent bedtime, getting morning daylight, avoiding late caffeine and alcohol—can help prevent high nighttime cortisol levels. If you find that night sweats spike your cortisol in the middle of the night, a clinician may recommend menopausal hormone therapy. (Just know that hormone therapy is prescribed to treat symptoms like night sweats themselves, not as a direct “cortisol-lowering” therapy.)

Does low cortisol cause weight gain?

Low cortisol (adrenal insufficiency) is more likely to cause weight loss than weight gain. In fact, one of the primary symptoms is a loss of appetite.