We all experience stress to some degree. Major life events — such as the loss of a loved one or the ending of a relationship — often result in stress. Work, financial pressures, and family matters can also be a source of stress: according to Statistics Canada, slightly more than one in four Canadian workers described their day-to-day lives as highly stressful.
The relationship between sleep and stress is profound and cyclical; stress can prevent us from falling asleep, and not getting enough sleep can make us stressed. A 2022 poll conducted in British Columbia revealed that most Canadians are unable to meet Health Canada’s recommended sleep guidelines, and half are finding it more difficult to drift off at night due to financial anxiety.
It’s impossible to completely avoid stress in our lives. However, when we are stressed, high-quality sleep can alleviate symptoms and deliver a range of additional health benefits.
Healthy cortisol levels
Cortisol is a hormone produced by the adrenal glands. Its main purpose is to regulate our response to stress, but cortisol also affects various other aspects of the body:
- The metabolic system, or how our bodies convert food to energy
- The sleep-wake cycle
- Blood pressure
- Blood sugar levels
While short bursts of cortisol may help limit inflammation, having chronically elevated cortisol levels can be detrimental to your health. Research suggests that heightened cortisol levels are associated with poorer cognitive function — too much cortisol in the blood can also lead to inflammation, persistently high blood sugar levels, and disruptions to sleep.
The hypothalamic-pituitary-adrenal (HPA) axis is a neuroendocrine system that controls our response to stress and regulates many other functions within the body. When the HPA axis’ processes are disrupted, the effects can be felt in your sleep cycle. Maintaining a healthy sleep schedule and getting high-quality rest can help promote healthy cortisol levels and reduce stress.
Regulates immune system
Studies have shown that stress affects the immune system in different ways, both in the short term and over an extended period of time. The immune system plays a key role in fighting off disease, preventing infection, healing wounds, and maintaining our overall well being.
A growing body of research suggests that sleep has a significant influence on the function of our immune systems, helping to build immunity and manage important cellular processes. Not getting enough sleep can negatively affect the immune system, but getting the right amount of good-quality sleep can support immune function and give the body and brain time to recover from the stresses of daily life.
Stress often produces feelings of anxiety, the mental and physical effects of which can be far-reaching. Anxiety can cause mood imbalances, reduced concentration, and increased irritability. Physically, anxiety may lead to muscle tension, rapid breathing and heartbeat, trembling, sweating, gastrointestinal distress, and tiredness.
When we don’t get enough sleep, our mood and emotional health suffers. How much we sleep each night influences how well we can cope with stress. When a person doesn’t get enough sleep, the deprivation behaves like a chronic stressor. The brain’s functions are impaired, which can result in memory loss, brain fog, depression, and confusion. All of these symptoms make it much more difficult to manage stress and anxiety.
A 2019 study involving a group of young adults found that anxiety levels dropped significantly after a full night of sleep: this reduction was even more pronounced in people who spent more time in the deep, slow-wave, non-REM stage of sleep.
During sleep, we are able to recover and heal. Getting enough good sleep can help ensure the brain and body are adequately prepared to respond to and deal with stress.
Keeps you mentally alert
While we are awake, neurons in our brains produce a powerful molecule called adenosine. Adenosine accumulates in the brain, and this build-up is understood to increase feelings of tiredness. During sleep, our bodies have the opportunity to clear adenosine from our systems, allowing us to feel more alert when we awaken.
We sleep, in part, to heal our bodies — but the restorative properties of sleep also extend to the brain. A 2021 study involving military veterans with traumatic brain injuries found that participants who slept poorly had more evidence of enlarged spaces associated with the development of dementia in the brain and more post-concussive symptoms.
Sleep gives our brains the chance to rest and recover, and it may play a critical role in the healing of brain injuries. A good night’s rest can boost mental alertness and prepare us to better handle life’s daily stressors.
Helps balance emotions
Mood and sleep share a close relationship. Feelings of irritability and sadness are common when a person doesn’t get enough sleep, and they may be more vulnerable to stress and mood swings.
Even partial sleep deprivation can have a significant effect on emotional well being. Participants in a study by researchers at the University of Pennsylvania were asked to limit themselves to 4.5 hours of sleep per night for one week. At the end of the week, they reported feeling more mentally exhausted, stressed, angry, and sad. After returning to their normal sleep schedules, the participants noted a dramatic improvement to their mood.
Without enough sleep, our ability to regulate and express our emotions is diminished. On the other hand, getting a sufficient amount of high-quality sleep can help balance emotions and ease feelings of stress.
Practising good habits before bedtime and following a consistent sleep schedule can help you get the rest you need when you’re experiencing stress. Consider incorporating relaxing activities like yoga, reading, or a warm bath into your nighttime routine to help you unwind if you’re having trouble sleeping because of stress. If your day-to-day life is being affected due to sleep loss from stress, consult your doctor for guidance and treatment.