How does cortisol affect stress?

We all have our own particular relationship with stress. And thanks to the pace of the modern era, stress and anxiety can intrude on our day-to-day lives in ways that feel overwhelming or constant.

While the body’s stress response is meant to be a survival tool to help us respond to physical danger, it can also be triggered by the non-life-threatening stimuli that abound in our world, like rush hour traffic, difficult coworkers, upcoming exams, or financial strain.

But where do these feelings of stress come from, exactly?

You might associate stress and anxiety with cortisol, which is, after all, known as the “stress hormone.” This is the hormone that produces the fight-or-flight response that historically helped our ancestors survive in a world full of physical dangers. However, cortisol wasn’t meant to be constantly activated in the way that twenty-first-century life tends to do, and too much of this hormone (or too little) can spell bad news for your overall health.

Getting a better understanding of cortisol, how it works, and what it does to your body can help you understand that invisible monster that plagues us all: stress. 

Although cortisol is most associated with stress --- and it is, indeed, the body’s main stress hormone --- it also plays a part in many of the body’s systems and is actually necessary for health.

It’s not all bad: cortisol is involved in metabolism, blood pressure regulation, memory formation, the sleep/wake cycle, energy levels, inflammatory response regulation, and more. It affects the body’s immune, nervous, reproductive, cardiovascular, respiratory, and other systems, and it helps keep these vital systems running as they should, which is why too little cortisol can also be bad for you.

This hormone is produced by the adrenal glands, which are found above each kidney. The pituitary gland at the base of the brain regulates cortisol production, and it tells the adrenal glands when to make cortisol and release it into the bloodstream. Once in the bloodstream, this hormone interacts with the various bodily systems mentioned above, supporting immune response, blood pressure regulation, and much more. 

Our bodies are constantly responding to both external and internal stressors. These take a wide variety of forms in our day-to-day lives; external stressors can come in the form of financial strain, upcoming deadlines, or similar, while internal stressors can arise from self-pressure, social anxiety, or other emotion-based stimuli. There are plenty of potential sources of stress, both in the world around us and in our own heads.

Here’s what happens when the body perceives stress of any kind: first, the body determines the degree of the threat in order to elicit a proportional response. Then, the sympathetic nervous system activates to boost the body’s alertness, respiration rate, and heart rate. All of this happens quickly via the amygdala, hypothalamus, and neurotransmitters like epinephrine.

So the question is, when does cortisol kick in?

Cortisol enters the picture after the process above happens if the perceived threat doesn’t disappear. Cortisol is what allows the body to maintain high levels of alertness throughout the duration of a stressful event. It pauses or slows down other bodily functions to reserve energy for the fight-or-flight response. This hormone directs the body’s glucose stores to provide the energy needed for the body to remain on high alert, maintaining the heart rate and blood pressure at high levels and directing blood to the muscles.

Perceived stressors, whether internal or external, make your body produce cortisol. This is the body’s way of responding to a potential threat, and the release of cortisol is how your body prepares its various systems to face those stressors. Even if something isn’t life-threatening (like an upcoming deadline), if you perceive it as a stressor, it can stimulate cortisol production that will help you overcome the issue at hand.

When everything is functioning correctly, the release of cortisol is a good thing. It can speed up your reaction time when someone cuts you off in traffic or help you focus when giving an important presentation.

But where things can go sour is when cortisol release doesn’t turn on and off like it’s supposed to. This can happen if you experience constant feelings of stress. Cortisol is intended to be released in occasional doses that help you power through stressful or potentially threatening situations --- but if you feel stressed or threatened constantly, cortisol production can’t turn off, which can lead to serious health effects from the strain this places on your body.

There’s a direct correlation between stress and cortisol. In an ideal scenario, cortisol releases in the body only when there is a threat that the body needs to react to, then stops when the threat has passed.

However, chronically elevated cortisol levels can feed into the experience of stress. This hormone creates many of the physiological responses we associate with stress: elevated heart rate and blood pressure, tensed muscles, slowed digestion, sweating, etc. If your body is unable to shut off the production of cortisol and return all systems to normal after a perceived threat --- or if a stressor persists in an ongoing or chronic way --- then your body’s stress response will continue. The harmful effects of chronically elevated cortisol are associated with Generalized Anxiety Disorder in adults as well as a variety of other health issues.

High cortisol can both be caused by (and can bring about) stress, but it can also be related to other factors like pituitary gland issues, medication side effects, estrogen therapy or pregnancy, athletic training, alcoholism, or malnutrition. When too much cortisol is the result of an underlying health issue, you may experience it as stress or anxiety.

There are many health effects of elevated cortisol beyond feeling stressed. Because this hormone affects so many of the body’s systems, it can throw a lot of things out of whack when it’s not functioning as it should.

Chronically high cortisol can cause weight gain around your abdomen and in your face, acne, too-high blood sugar levels, decreased immune function and slowed healing, gastrointestinal issues, severe fatigue, muscle weakness, mood swings and irritability, brain fog and difficulty concentrating, high blood pressure, low libido, and headaches. Basically, the effects of elevated cortisol are serious and extensive, and they can lead to or exacerbate long-term health issues.

If you have any of the symptoms of high cortisol or if you experience chronic stress or anxiety, you can get a cortisol test that measures the levels of the hormone in your blood, saliva, or urine. This type of test can clue you into what’s going on with your cortisol levels and what you can do to better support your health.

Base is one option when it comes to cortisol testing, and you can use the stress testing plan at home without having to make a doctor’s appointment or lab visit. Plus, this particular test is geared toward uncovering the root causes of stress in general, which means that it goes beyond just measuring cortisol; it also measures other stress indicators including thyroid hormone levels, DHEA, and testosterone, as cortisol isn’t the only culprit when it comes to stress. This comprehensive view of your health offered by Base can help you understand exactly what’s happening to your body so that you can give it what it needs.

Some ways that you can naturally lower cortisol levels include setting a healthy sleep schedule, getting gentle exercise and outdoor time most days, eating a nutritious diet that includes healthy carbs, meditating or deep breathing, and supplementing with adaptogens like ashwagandha. In general, taking steps toward a healthy and positive lifestyle can help you regulate stress, but it’s also important to be equipped with health data because sometimes these lifestyle changes aren’t enough to move the dial.

That said, a singular cortisol test taken on a random day won’t necessarily give you all the needed insights to improve your long-term wellness. Monitoring your cortisol over time can help you move toward your health goals --- but you don’t necessarily want to visit the doctor every month. That can add up quickly.

Base’s at-home testing can help you track cortisol and other hormone and nutrient levels over time, providing you with lifestyle and supplementation recommendations tailored specifically to those levels. With this helpful tool in your back pocket, you can figure out exactly what wellness looks like for you and find the best ways to manage your stress.