Man facing stressYou’ve probably heard that stress has a significant impact on the immune system. But have you wondered why this is?


Different systems throughout the body interact with each other through complex processes. Psychoneuroimmunology is the study of psychological processes on the nervous system and the immune system. Stressful events and our emotional response to these trigger the hypothalamic-pituitary-adrenal (HPA) axis which provokes the release of several hormones including glucocorticoid hormones such as cortisol. Chronic stress results in glucocorticoid receptor resistance, further disrupting the HPA axis function and interferes with the regulation of inflammation and immune function. 


Stress also triggers us to enter a sympathetic nervous system (SNS) state – also known as fight, flight and freeze. The opposing state is the parasympathetic nervous system, also known as rest, digest and sex. During stressful situations, blood flow and energy are redirected to more essential organs and taken away from other organs such as your gut (which will be further discussed in another article). This is a survival mechanism and is important for acute, dangerous situations, however, other issues arise when we are experiencing chronic stress which in today’s society is all too common. Living in a constant SNS state leads to impaired digestive function, this means reduced nutrient absorption which can further impair our immune function.  


It isn’t as easy as telling your mind, emotions, body to not stress – this attempt can lead to more stress being experienced because you believe “you should not be stressed”. Rather, practising kindness and compassion towards yourself during these times and taking some time out when needed. Gentle therapeutics like flower essences and herbal medicine may help to support the nervous system and help the stress response. Alternatively, some other ways to help support your nervous system are listed below.


Reduce Media Exposure 

Yes, it is important to stay informed, know the latest rules and what you can or can’t do. But scrolling news stories or having the news running in the background all day further heightens our sympathetic nervous system. This is particularly important at night time, avoid the night time news as this activates SNS state at night time when our natural cycle is ready to wind down.


Get Regular, Good Quality Sleep 

Sleep is needed for all areas of health, including immune function. Sleep is when our body gets a chance to repair and restore. In stressful situations, sleep may be impacted because of the HPA axis activation. Things that can help sleep: 

  •  Avoiding blue and bright lights (tv, phone, laptop) an hour before bed as these lights send messages that it is day time, disturbing the natural circadian rhythm and melatonin production.
  • Creating a nightly ritual, reading a book/magazine by lamplight which isn’t too exciting or stimulating.
  • Drinking herbal tea specifically chamomile, passionflower, lemon balm or valerian root which have calming and mild sedating properties
  • Create a dark bedroom environment and keep the bedroom for sleep and sex rather than for work and watching television 


Nutrition Is Important

High-stress times require increased nutrient intake as being in an SNS dominant state utilises a greater quantity of certain nutrients within your body – particularly B vitamins, magnesium, zinc and vitamin C. A deficiency in these nutrients also contributes to heightened stress, creating a vicious cycle of deficiency and greater requirements. If your diet is less than average during these times, wholefood powders or nutrient supplementations may be of benefit for the short term, however there are a lot of poor quality products out there, so look at the ingredients.


Regular Outdoor Exercise 

Through regular exercise, you are enhancing not only your immune system but supporting your nervous system and digestive function. Vitamin D is also an important nutrient for the immune system as well as hormone production and bone health.   

Aim for a balance of low impact gentle exercise (yoga, walking, pilates) and rigorous cardio or weight-bearing exercises. Aim for exercise outdoors if possible, exposure to fresh air and ‘greenspace’ helps to activate the PNS and reduce stress.


Adults and children who have regular exposure to green space – parks, gardens, forests etc have a more positive outcome in mental health with reduced levels of stress, anxiety, and depression


Meditation and Relaxation Exercises 

Sitting meditation in silence isn’t for everyone, however, there are different forms including guided meditations, walking meditations, breathing exercises, and mindfulness activities such as colouring in.  You can find many guided meditations on Youtube or apps like Insight Timer and Headspace. Mindfulness, meditation and relaxation exercises help to stimulate the PNS and reduce stress while improving mood. 


Connect With Friends and Loved Ones 

It may be a challenging time to be able to have face to face interactions, but loneliness and isolation can lead to poor physical health which includes depression and immune dysregulation. If there are still restrictions in your area, look into regular phone or facetime chats with friends and family, go exercising with a friend, call beyond blue, lifeline or another organisation.




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Dhabhar FS (2014) Effects of stress on immune function: the good, the bad, and the beautiful. Immunol Res 58:193–210

Hedblom, M., Gunnarsson, B., Iravani, B. et al. Reduction of physiological stress by urban green space in a multisensory virtual experiment. Sci Rep 9, 10113 (2019).

LeRoy AS, Murdock KW, Jaremka LM, Loya A, Fagundes CP (2017) Loneliness predicts self-reported cold symptoms after a viral challenge. Health Psychol 36:512–520