Stress is a natural part of life, but when it persists, it can significantly disrupt your sleep. At the core of this disruption is cortisol, the body’s primary stress hormone.

Cortisol is released during the “fight or flight” response - a survival mechanism designed to help us respond to threats. However, in today’s world, modern stressors such as work deadlines, personal challenges, or late-night emails can trigger the same hormonal response.

It’s important to note that cortisol isn’t inherently bad - it plays a crucial role in maintaining our circadian rhythm. However, when cortisol spikes too close to bedtime, it can make falling asleep difficult. Physical symptoms like an elevated heart rate and muscle tension, combined with mental stress and overthinking, can prevent the body from relaxing, compounding sleep difficulties.

Understanding Cortisol

Cortisol plays a vital role in regulating the body’s response to stress, managing energy levels, and maintaining alertness. It is produced by the adrenal glands, small triangular-shaped glands located on top of each kidney.

The Role of Cortisol in the Stress Response

Cortisol is essential during the “fight or flight” response, where it helps the body mobilize energy by increasing blood sugar levels and suppressing non-essential functions like digestion. This ensures the body has the energy it needs to handle immediate challenges or perceived threats.

Cortisol's Daily Rhythm

Under normal conditions, cortisol follows a predictable daily rhythm. Levels peak in the morning, helping us wake up and feel alert, and gradually decline throughout the day. By evening, lower cortisol levels allow melatonin to rise, signalling the body that it’s time to rest. For a deeper dive, check out our blog posts on circadian rhythms and the role of melatonin in sleep.

Cortisol & Sleep

High cortisol levels keep the brain alert. Depending on the situation this can be a desirable or bad thing. A sprint up the stairs in the office might be good to overcome the post lunch drowsiness but a hard workout late at night can increase the time you need to fall asleep at night. High cortisol levels just prior to sleep will reduce the quality of deep sleep and you may wake up more often during the night.

We appreciate that for some of you a late workout is the only option to get exercise in at all. If this is the case, go for it. Exercise is extremely important and the benefits of it might outweigh the cost of a slightly slower sleep onset. Everybody must find what works for them given schedule and circumstances.

We'd also like to mention, that a cortisol spike just before sleep is not the end of the world. What we should aim for is to improve our sleep in the long term and strive for consistency. Also, we wouldn't worry too much about cortisol spikes during the day - these are part of our biological system and are a healthy response to the outside world.

Impact of Elevated Cortisol on Sleep

Things become a bit more problematic once cortisol levels are elevated for a prolonged period of time through chronic stress. That's when it throws our system into tailwinds.

If we are subject to consistent stressors and our system produces a lot of cortisol over a long time period as a result (we're speaking weeks and months), that's when we speak of chronic stress.

Chronic stress hyperactivates the HPA axis (hypothalamic-pituitary-adrenal axis) which disrupts the cortisol’s natural decline. The cortisol remains in the system and isn't cleared out. Over time, this can lead to insomnia and irregular sleep cycles as the elevated cortisol interferes with the production of melatonin.

Managing Cortisol for Better Sleep

Managing cortisol levels can be challenging, especially with unpredictable schedules. There are some key strategies to keep in mind. While these might seem straightforward, implementing them consistently can be tricky. We may revisit these in another post to explore how they can fit into a busy lifestyle. Here are the main pillars:

Minimize exposure to stressors

Avoid constant smartphone notifications and chaotic, unstructured days, as they can contribute to elevated cortisol levels. Admittedly, this can be tough to navigate.

Incorporate regular exercise

Moderate physical activity helps lower cortisol over time. However, avoid intense workouts late in the evening, as they can spike cortisol levels.

Maintain a healthy diet

A balanced, nutritious diet supports overall hormonal regulation, which can help stabilize cortisol levels.

Limit stimulants and alcohol

Both can unnecessarily elevate cortisol, so moderation is key.

Stress management techniques

Activities like yoga, mindfulness, and meditation can effectively reduce stress and keep cortisol levels in check throughout the day.

Supplementation

Sometimes, supplements can provide extra support in managing stress and sleep if lifestyle adjustments are not enough or simply not feasible.

• Melatonin regulates the sleep-wake cycle, melatonin can help reset disrupted rhythms. Melatonin has it's place and is used widely to reset sleep schedules but we caveat that there might be some problems with it. See our deep dive on Melatonin.
• Magnesium can promote calmness and modulate cortisol spikes. See our deep dive on Magnesium.
• Adaptogens like ashwagandha, rhodiola and apigenin can help your body adapt to stress and bring cortisol levels back to baseline.
• GABA and L-Theanine: These compounds work to enhance relaxation by calming excitatory signals in the brain.

Conclusion

Cortisol is a critical part of our body’s stress response. If it gets out of balance, it can negatively impact sleep and overall health. There are lifestyle changes such as exercise and diet that can improve your stress response. Unfortunately, we work and life commitments sometimes get in the way of our healthy habits. In these instances supplementation might be a good way to regain control of your sleep and manage cortisol levels.

At Somio we have packed our SleepBites with the key ingredients to help you unwind and relax after a busy day in the office. Check out the best supplement for busy professionals here