Skip to main content

Verified by Psychology Today


Has 2020 Flatlined Your Cortisol?

The timing of cortisol release matters more than the overall amount.

You’ve probably heard about cortisol, the stress hormone that our bodies release in response to and in anticipation of stressful events. But does cortisol provide a needed boost of energy or cause wear, tear, and fatigue?

The most important feature of cortisol isn't how high or low it is, but if and when it fluctuates (its diurnal rhythm). The behavior, or pattern of its release, correlates with our ability to think, sleep, and even our ability to recognize how others are feeling. The key function of cortisol is its ability to rise and fall at the appropriate times to optimal levels; fluctuation is its superpower.

Has the chronic stress of 2020 caused your cortisol to flatline?

ZRT Labs, used with permission
Source: ZRT Labs, used with permission

It's 6:00 a.m., Monday morning, and you’re able to release enough cortisol to get washed and dressed, but then your childcare cancels and as you scramble to contact your backup plan, you step into the dog’s water bowl, rush to change socks, and knock over your fresh brew — the only hope you had for making it to work on time. The comedy of errors continues, each with another burst of cortisol to meet the task your brain-body anticipates based on what has already occurred and how you’re interpreting the current clumsy interaction with Monday morning. By lunchtime, you’re just a bit haggard, somewhat refreshed from a short walk and lunch and back to the unfriendly emails you avoided in the morning, knocking them out until the 3:00 p.m. slump when blood sugar, temperature, and cortisol naturally dip.

But it’s fine — you recover. The next day you are back to baseline with no lasting negative consequences.

But what happens when stress is daily, chronic, or severe? Trauma, loss, and relationship stress can impact cortisol’s release pattern and research shows that under certain circumstances, it can release more or less than normal, losing its most optimal rhythm and limiting its ability to match the required amounts for you to function optimally and feel good. This can also occur with a disrupted daily routine that many of us have experienced since the pandemic began. In fact, sustained heightened levels of cortisol during chronic stress can mask stress's negative impacts until after it is over and the body lets down.

Engin Akyurt/Unsplash
Source: Engin Akyurt/Unsplash

Circadian dysrhythmias, disruption of our day-night patterns, are interconnected with myriad other mental and physical health problems through its coordination or discoordination with respiration, cardiac function, liver, kidney, platelets, plasma, cytokines and inflammation, and even to our microbiome. These interconnected and dynamic relationships are still underappreciated as is the disruption that is caused by any number of illnesses, traumas, or stressors you may experience. Each part of your brain-body system is subject to circadian rhythms that underlie many other networks. The nested networks within our entire human brain-body system are not affected in isolation and therefore cannot be treated as such. If cortisol has lost its pattern, something else has too. It is not a variable living in isolation.

Besides helping you meet daily stress, cortisol has been there for you every single morning of your life (with few exceptions), increasing before your feet hit the ground in anticipation of your day. Perfectly timed neurochemicals and cascading hormones coordinate on the morning neural-freeway to awaken the brain's dynamic synaptic patterns, as well as prepare the liver, heart, blood pressure, temperature, and muscles for action.

Cortisol generally makes a ski slope shape (called the cortisol diurnal slope) with the peak in the morning that decreases throughout the rest of the day until its lowest point overnight. It rises to allow our analytical thinking, reasoning, and other executive skills to increase throughout the morning and reduce as the day goes on to more creative and less rigid ways of problem-solving and interacting with our environment. When functioning well, the brain-body enables additional cortisol release for unanticipated stressors as they arise.

But rather than viewing it dichotomously as high or low, good or bad, it may be more helpful to take a step back to observe your own pattern of energy and focus throughout the day. When do you feel at your best? If this is not in the first half of your day or if you never seem to feel energized or focused, the fluctuation of cortisol may have altered its pattern in an attempt to match what it anticipated your needs to be according to the stress you've been experiencing. For more ideas, read "10 Ways to Stay More Awake During the Day."

Marko Blažević/Unsplash
Source: Marko Blažević/Unsplash


Bishehsari, F., Voigt, R.M. & Keshavarzian, A. (2020) Circadian rhythms and the gut microbiota: from the metabolic syndrome to cancer. Nat Rev Endocrinol.

McKenna, H. T., Reiss, I. K., & Martin, D. S. (2017). The significance of circadian rhythms and dysrhythmias in critical illness. Journal of the Intensive Care Society; 18(2): 121–129.

Adam, E. K., Quinn, M. E., Tavernier, R., McQuillan, M. T., Dahlke, K. A., & Gilbert, K. E. (2017). Diurnal cortisol slopes and mental and physical health outcomes: A systematic review and meta-analysis. Psychoneuroendocrinology, 83: 25–41.

Fisher PA, Stoolmiller M, Gunnar MR, Burraston BO. (2007). Effects of a therapeutic intervention for foster preschoolers on diurnal cortisol activity. Psychoneuroendocrinology; 32(8-10):892-905.

More from Jessica Del Pozo, Ph.D.
More from Psychology Today