The short answer: it depends.
The body’s stress response includes secretion of a hormone called cortisol. In smaller doses and at certain times of the day, cortisol is beneficial- this is usually during an acute stress response. But during times of chronic, prolonged stress, we may be experiencing excess cortisol that can have a negative impact on our blood sugar and metabolism among other things.
First we need to understand what cortisol is, and why it may be high or low...
What is Cortisol:
Cortisol, often referred to as our “stress hormone” is released by the adrenal glands in small amounts in a circadian rhythm, and in larger amounts during times of stress. It can help regulate blood sugar levels and metabolism, reduce inflammation, and assist with memory formulation.
Cortisol follows a diurnal rhythm and is meant to be higher in the morning and taper off throughout the day (more on that later). Problems arise when anything about that pattern is off- whether it is consistently high or low OR it is higher or lower at certain points of the day than it should be (what might be called “rebound” cortisol).
Signs of HIGH cortisol:
✖️Belly fat gain
✖️Blood Sugar or Blood Pressure Issues
Signs of LOW cortisol:
✖️Low sex drive
How cortisol can prevent you from reaching your health and fitness goals
It impacts energy and cravings
When you’re stressed, cortisol taps into protein stores via gluconeogenesis in the liver, providing your body with glucose (aka energy) to help you fight or flee from a stressor. But when you’re chronically stressed, this elevated cortisol will constantly produce glucose and lead to increased blood sugar levels. On a smaller scale, this could lead to increased carbohydrate cravings and large swings in energy. On a larger scale, this may cause a long term insulin resistant state and potentially increase your risk for type 2 diabetes.
It may increase fat storage
Chronically elevated cortisol can lead to weight gain through visceral fat (the fat that surrounds your organs) storage as well as aiding in the development of mature fat cells. We already discussed how cortisol can increase blood sugar- consistently high blood sugar levels combined with insulin resistance leads to cells that are starved of glucose. Because these cells are essentially begging to be fed, our body will send more hunger signals to the brain causing you to overeat. Not to mention there are also some studies to support cortisol’s connection to cravings for hyper palatable foods. All of this of course results in eating above calorie needs, which will cause weight gain and fat storage no matter which macronutrient you indulge in.
It makes building muscle difficult
Cortisol is a catabolic hormone (one that breaks things down) that will break down molecules of both carbohydrates and protein. And because our body is looking for any energy source it can get its hands on in this catabolic state, it won’t hesitate to break down the protein stored in your muscles, making it harder for you to grow and maintain that functional mass.
It impacts your sleep
There’s a reason cortisol follows a diurnal pattern: high in the morning and tapering off throughout the day. It helps us WAKE UP. So, if we are experiencing chronically elevated cortisol all day or rebound cortisol that spikes in the evenings, we will most certainly have trouble falling and/or staying asleep at night. Those with this issue often feel “tired and wired” in the evening and have trouble getting going in the morning. And if you’re not getting adequate sleep you’ll be more likely to have subpar workouts, low energy, increased cravings for hyper palatable foods, and poor recovery.
It messes with your gut
Cortisol activates the sympathetic nervous system, aka our “fight or flight” response. When this happens, our parasympathetic nervous system (aka our “rest and digest”) must then be suppressed, since the two systems cannot operate in tandem. Can you see where I’m going with this? Your body doesn’t care if you’re in the middle of lunch; if you stress it out by scrolling emails while eating, it is going to put all of its effort into fueling that sympathetic nervous system and potentially wreak GI havoc on your body.
So…what do you do if you have these issues and suspect cortisol is the culprit?
I will ALWAYS recommend testing and working with a qualified practitioner. I offer something called a Dutch Test in my practice that tests cortisol and sex hormones. However, if this isn’t something in the cards for you right now you can also try some simple lifestyle changes, such as:
- Practice stress relieving techniques
- Stick to boundaries with work
- Don’t scroll or read email while eating
- Monitor caffeine intake
- Get 7-9 hours of sleep
- Follow a balanced exercise plan that includes strength training
- Ensure adequate recovery/rest days
Got cortisol questions? Drop them below!