How are sleep and stress related?
Stress triggers a range of reactions in our body (this is called the “stress response”) including the release of the stress hormone, "cortisol". Stress puts us into a state of hyperarousal, as if the brain and body is on high alert. Our reaction to stress is part of our survival instinct, in the wild we would want to be on high alert to survive.
To make matters worse, when we are sleep deprived our body makes more cortisol. This is because lack of sleep is perceived by our brain as a "stressor". Stressors fall into two categories: physical stressors and psychological stressors. Physical stressors include sleep deprivation, low blood sugar levels, physical injury and overly intense exercise. Psychological stressors are what we more typically associate with stress such as worrying about something. So sleep deprivation is a physical stressor, triggering the stress response and causing our body to produce more cortisol. It's a vicious circle where psychological stress causes us to be on "high alert" and therefore no sleep, and then our sleep deprivation causes us to be more stressed. High levels of cortisol also drives inflammation - too much can be bad news for our health in many ways, including our skin.
When our stress is related to modern day problems rather than true survival challenges, (e.g. a tight deadline at work vs being chased by a lion), a state of “high alert” is not useful - especially when it impacts our ability to get a good night's sleep. Looking at ways to dial the stress down, especially in the evenings, is essential for our beauty sleep and overall health.