Guest post written by Chiara Toscano, recent Dietetics Graduate from the University of Ottawa, and Miriam Bendayan, Dietetics Student from the University of Ottawa, edited by Jennifer Neale, Registered Dietitian and Certified Intuitive Eating Counsellor.
If you’ve been told high cortisol is the reason for your weight gain, fatigue, or “cortisol belly,” you’re not alone. Cortisol seems to be having a moment on social media.
You have probably heard phrases like “cortisol face” or "cortisol belly", seen influencers sharing their “cholesterol-lowering hacks,” or been told that high cortisol is the reason you're tired, bloated, gaining weight, losing hair, or just feeling off in general.
And while cortisol is a real hormone with real effects on the body, the way it’s talked about online often strips away a lot of important nuance.
If you’ve been searching for how to lower cortisol naturally, it’s important to understand how cortisol actually works before trying to change it.
So let’s slow this down for a second.
What actually is cortisol? Should you be worried about it? And is trying to “lower” it helpful… or could it be doing more harm than good?
Before we talk about lowering cortisol, it helps to understand what it actually does in the body.
Cortisol is a hormone your body makes naturally. It’s produced by your adrenal glands, which are small organs that sit above your kidneys, and it’s regulated by a communication system between your brain and those glands called the HPA axis.
You’ll often hear cortisol called “the stress hormone,” but that label is a little misleading. Cortisol doesn’t exist to stress you out. It responds to stress and exists to help you function.
Cortisol affects almost every system in your body, including your immune system, metabolism, nervous system, reproductive system, and even your skin.
One of its most important roles is helping your body respond to stress. When something feels threatening or overwhelming, cortisol helps make more energy available so your brain and body can respond.
In essence, during a period of stress, a part of the brain tells the body to release cortisol. Cortisol increases the availability of sugar to our brain, which gives the brain extra fuel to be able to think and move. This allows our body to stay on high alert and deal with the stress (this is commonly referred to as a state of ‘fight or flight’).
That’s your body’s survival instincts kicking in, not a sign that something is broken.
Cortisol isn’t meant to stay at one steady level all day.
It naturally rises in the morning to help you wake up and feel alert, and falls in the evening to help you wind down. On top of that, it spikes temporarily during stressful moments like running late, having a tough conversation, or pushing through a hard workout.
This constant rising and falling is normal.
Which is why trying to “track” cortisol day-to-day, or attempting to micromanage it based on how you feel, is often frustrating and misleading.
This is where things often get blurred online.
Social media can make it feel like everyone has high cortisol levels, but true cortisol-related endocrine disorders are actually rare. There are medical conditions where cortisol levels are consistently too high or too low, and they’re serious enough that they require proper medical care.
One example is Cushing’s disease, which happens when the body is exposed to high cortisol levels for a long period of time. This usually isn’t random. It’s often related to other medical issues, like tumours, or long-term use of corticosteroid medications to treat other conditions. Over time, this can lead to things like unexplained or significant weight gain, high blood pressure, blood sugar issues, muscle weakness, easy bruising, and changes in where the body stores fat, often around the face, neck, and abdomen. Some people may also notice increased facial hair growth.
On the other end of the spectrum is Addison’s disease. This happens when the body doesn’t make enough cortisol, most commonly because the immune system attacks the adrenal glands. People with Addison’s often deal with ongoing fatigue, unintended weight loss, low blood pressure, dizziness, nausea, and darkening of the skin in certain areas. Since cortisol plays a big role in things like blood pressure, energy levels, and stress response, this condition requires lifelong medical treatment.
Two things can be true at once. Cortisol-related medical conditions like Cushing’s and Addison’s disease are very real and can be life-changing for the people who live with them. They involve sustained, abnormal cortisol levels and are diagnosed through proper medical testing. These conditions aren’t caused by food choices, exercise habits, or stress alone, and they deserve to be taken seriously.
At the same time, what most people are seeing online about “high cortisol” usually isn’t referring to these medical conditions. Maybe they are referring to people having cortisol at the higher end of normal, but at the end of the day, that’s still normal and not something to panic over.
For most of us, cortisol naturally rises and falls throughout the day and during stressful periods, and that’s a normal part of how the body works. If something feels persistent or genuinely concerning, checking in with a healthcare professional is always the right step. But for most people, cortisol doesn’t need fixing, just understanding.
This is one of the most common claims online. Cortisol gets blamed for weight gain, especially around the stomach or face.
If we look at the medical conditions we just discussed, such as Cushing's disease, where cortisol levels are consistently very high, changes in body composition can happen. People living with this condition may experience fat redistribution, muscle weakness, and changes in blood sugar regulation as part of a broader hormonal disorder that requires medical care. That situation is very different from the normal cortisol fluctuations that occur with everyday stress, busy schedules, poor sleep, or tough workouts.
For most people, temporary increases in cortisol are part of a healthy stress response. They do not automatically cause weight gain! Body weight is influenced by many factors, including overall energy intake, sleep, movement, medications, genetics, and long-term stress patterns. No single hormone works in isolation.
That said, cortisol can have an impact on appetite and eating behaviour, especially during periods of chronic stress. If stress is very high, this is also likely to impact sleep and physical activity as well. All those factors combined could lead to body changes, but cortisol alone does not cause weight gain. In Part 2, we break down how nutrition and lifestyle factors influence cortisol levels and overall stress response.
Cortisol isn’t a bad hormone. It’s an essential one. You need it to wake up in the morning, regulate blood sugar and blood pressure, manage inflammation, and respond to stress. In healthy people, cortisol is tightly regulated by the brain and is meant to rise and fall throughout the day.
For most people, the issue isn’t cortisol itself. It’s the stress that comes from trying to control it. Restricting food, cutting out carbs, over-exercising, or constantly worrying about doing everything “right” can actually increase stress on the body and push cortisol higher, not lower.
Many of these influencers are selling a product or a program to help the problem that they have created. Because cortisol naturally fluctuates during the day, there is no way of testing whether the solutions that they are providing are actually working. Even if you tested your cortisol every day at the same time, there’s no guarantee that you’d get any meaningful data.
If cortisol isn’t the villain it’s often made out to be, then what actually supports healthy cortisol levels?
More importantly, what supports your health without adding more stress to your life?
In the next post, we’ll break down what the research says about food, movement, sleep, and stress, and how to support your body in ways that are realistic, sustainable, and not driven by fear or expensive supplements.
Need a quick summary of this blog post? Here are 5 commonly asked questions about high cortisol levels.
True high cortisol levels caused by medical conditions like Cushing’s disease can lead to symptoms such as significant weight gain (especially around the face and abdomen), high blood pressure, muscle weakness, easy bruising, and blood sugar changes. If you think that you have these symptoms, you should talk to your doctor.
High cortisol levels as a response to stress are unlikely to lead to the symptoms above on their own. Remember that cortisol will rise naturally as a response to stress AND will also lower naturally on its own.
Stress temporarily increases cortisol as part of a normal survival response. In healthy individuals, cortisol naturally rises and falls throughout the day. Occasional stress does not mean your cortisol levels are chronically elevated. If you have chronic stress, that is a sign to manage your stress, not get hyper-focused on your cortisol levels.
Cortisol alone does not directly cause weight gain in most people. While chronic stress may influence appetite, sleep, and movement patterns, body weight is shaped by many interacting factors, only some of which you as an individual can control. Persistent, extreme elevations in cortisol are typically linked to medical conditions, not everyday stress.
“Cortisol belly” and “cortisol face” are terms popularized on social media (and really just designed to make you feel bad about yourself). While severe medical conditions involving prolonged high cortisol can affect fat distribution in the body, normal stress-related cortisol fluctuations do not automatically cause abdominal weight gain.
If you have persistent symptoms that concern you, speak with a healthcare provider. Cortisol testing requires proper medical context and timing, as levels naturally fluctuate throughout the day.
Want to learn more about cortisol and whether you can actually lower high cortisol levels with food, exercise, sleep, and stress management? Check out this blog post.
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