How we are affected by stress.

 Photo by Karina Carvalho on Unsplash

Stress is a natural part of life, and we are well adapted to deal with certain types and levels of stress. However, in today’s society there is an alarming upward trend in people suffering from anxiety. According to American Psychological Association[1]more than one-third of adults report that their stress increased over the past year. Twenty-four percent of adults report experiencing extreme stress, up from 18 percent the year before.

We can separate stress into two broad categories: Eustress creates a "seize-the-day" heightened state of arousal, which is invigorating and often linked with a tangible goal. When we feel a sense of excitement (whether good or bad) we produce adrenaline to start up the flight or fight mechanism. Cortisol is released to fuel the body for this state. Cortisol levels return to normal upon completion of the task. Distress,or free-floating anxiety, doesn't provide an outlet for the cortisol and causes the fight-or-flight mechanism to backfire on us.

Neuroscientists at the University of California, Berkeley, have found that chronic stress triggers long-term changes in brain structure and function.[2] 

In cases of chronic stress cortisol levels remain high and affect the brain in several ways:

  1. It can disrupt synapse regulation, which causes a loss of sociabilityand avoidance of interactions with others.
  2. It can shrink the prefrontal cortex(This brain region has been implicated in planning complex cognitive behaviour, personality expression, decision making, reason, logic and moderating social behaviour). This is like having our thinking “taken off-line”.
  3. It can increase the size of the amygdala, which is positioned to initiate and coordinate an unconscious, primitive stress reactionthroughout the brain and body. This leaves the brain in a state of heightened receptivity to stress. 
  4. It can shrink the hippocampus, which regulates memory and emotions.[3]. Daniela Kaufer, UC Berkeley, performed a series of experiments observing the response of white and grey matter in the brain to chronic stress and reports that “our findings could provide insight into how white matter is changing in conditions such as schizophrenia, autism, depression, ADHD, PTSD and suicide.”
  5. It can kill brain cellsparticularly in the areas associated with memory and learning, according to the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology,Rockefeller University.
  6. Stress lets toxins into your brain.The blood-brain barrier is a group of highly specialized cells that act as your brain’s gatekeeper. This semi-permeable filter protects your brain from harmful substances while letting needed nutrients in. Stress makes the blood-brain barrier more permeable, in effect making it leaky, allowing in pathogens, heavy metals, chemicals, and other toxins. Having a leaky blood-brain barrier is associated with brain cancer, brain infections, and multiple sclerosis. 


Alongside of these mind and emotion-altering physical effects chronic stress can also lead to other significant problems, such as increased risk of heart disease, high blood pressure and diabetes. Other systems of the body stop working properly too, including the digestive, excretory and reproductive structures. Toxic stress can impair the body’s immune system and exacerbate any already existing illnesses. In essence, stress, whether acute or chronic, can cause debilitating and distressing symptoms. Things to look out for in yourself or others include: 

  • Excessive or unwarranted anger/frustration
  • Impatience with self or others
  • Mood swings
  • Suicidal thoughts
  • Excessive defensiveness, paranoia, hostility
  • Feeling overwhelmed
  • Forgetfulness, mental fog/confusion
  • Sleep problems; insomnia, nightmares
  • Crying spells
  • Uncontrollable thoughts/ racing thoughts
  • Nervousness
  • Excessive worry and/or fear
  • Depression
  • Obsessive or compulsive behaviours

Thankfully there are simple steps you can take to help alleviate many of these symptoms and reduce your anxiety and cortisol levels.

  1. Regular Physical Activity: Whether a sport, or Aerobic activities, such as dancing, running or the gym will recreate the “fight” response by letting out aggression (without hurting anyone), thus reducing cortisol. It also will increase confidence so helping to reduce fear (which increases cortisol). Exercises such as Tai Chi, yoga, QiGong, etc. help redress the balance of the body and bring about a sense of calm.
  1. Meditation has been proven to adjust the brain waves bringing them to a frequency that induces the body and mind to relax more and reduces stress and cortisol levels. In a recent study published in the neuroscience journal Brain Research Bulletin6, it was shown that the brains of people who meditate had elevated alpha rhythms, which is associated with extreme focus, relaxation, learning, creativity, and peak performance. Sara Lazar, aneuroscientist at Harvard Medical School7found the amygdala decreased in size, and three other areas changed: the TPJ, which is associated with perspective taking, empathy and compassion; the left hippocampus, (learning, cognition, memory and emotional regulation) and the posterior cingulate (involved with mind wandering and self-relevance).
  1. Increase your social contact. Talk to someone. We tend to decrease our connections with others when we feel overwhelmed, stressed or frightened. The "tend-and-befriend" response increasesoxytocin89and reduces cortisol. Make an effort to spend real face-to-face time with loved ones whenever you can, but phone calls and even social media can reduce cortisol if they foster a feeling of genuine connectivity. Two studies published this week in the journal Science illustrate that social aggression and isolation lead to increased levels of cortisol in mice, which trigger a cascade of potential mental health problems — especially in adolescence.
  2. Close-knit human bonds are vital for your physical and mental health at any age. Recent studies have shown that the Vagus nerve also responds to human connectivity and physical touch to relax your parasympathetic nervous system.9
  3. Having fun and laughing lowers levels of stress hormones and helps the brain create new neural pathways. We can suddenly come up with new insights and solutions after a good laugh.
  1. Sleep: this is when the body does its healing and repairing. Unfortunately this can also be one of the first things to become disrupted during times of great stress. So: mediate or relax before bed. Eliminate or reduce caffeine and alcohol several hours before. Keep your bedroom cool and relaxing. No phones, gadgets or excess clutter.
  1. Become aware of your stress triggers and try to minimise them.
  1. Manage your time so that you don’t become overburdened. Prioritise and diarise your tasks.
  1. Learn to say no to the things that won’t help you or you feel are too much for you
  2. Listening to music that you love, and fits whatever mood you're in, has been shown to lower cortisol levels.
  3. Try herbal supplements and drink teas such as chamomile, dandelion, peppermint, sage, nettle, lemon balm.
  4. Turn of phones, gadgets/laptops at least two hours before bed. Your brain needs time to unwind, and the blue light given off has been shown to affect levels of melatonin and other hormones that regulate quality of sleep.

Helen Lickerish 



3. D. Kaufer et al Molecular Psychiatry volume 19, pages 1275–1283 (2014) doi:10.1038/mp.2013.190