The Parasympathetic (rest & digest) and Sympathetic (fight & flight) nervous responses are our body’s automated and involuntary body functions. Responsible for breathing, heartbeat, digestion and elimination, both systems act together to maintain the body’s natural balance (homeostasis), and we can play a pivotal role in supporting them. The food we eat and our lifestyle choices can have a significant impact on how these systems respond.
Sympathetic Nervous System (SNS)
This is our stress response. It prepares you to take flight, fight or freeze.
Our heart beats faster, our breath becomes fast and shallow, and our alertness increases. There is an increase in blood flow to skeletal muscles. The brain activity changes from areas that give us clear thinking, calm, mindfulness activity to a state of stimulation, anxiety and agitation.
Our gut becomes inactive, we lose appetite, relaxation becomes difficult, and this has a knock-on effect with sleep disturbances, difficulty with elimination and a build-up of toxicity. It suppresses our immune system and reproductive functions.
Hormones, particularly adrenaline, rush through your body, making you feel anxious; this all uses masses of energy, creating exhaustion.
Despite the negatives, the SNS is necessary for our survival. This automatic response makes us move out the way of an oncoming vehicle or remove our hand from a heat source
that would otherwise burn us.
However, constant overstimulation of the sympathetic nervous system is involved in many health problems; this can lead to anxiety disorders that can overwhelm us. Exhaustion then leads to burn out and a host of health complaints from heart disease, elevated blood pressure, diabetes, fatigue etc.
Taking high levels of stimulants like caffeine and sugars and excessive alcohol can also provoke a stress response.
Parasympathetic Nervous System (PNS)
This is our relaxation response, our brake pedal; it calms us down, preparing us to rest and digest and sleep.
Our heartbeat slows to a nice steady rhythmic pattern; we breathe in full and slow. We have increased blood flow to the gut, whilst lungs and brain return to working normally. Our gut is active; this helps us digest and absorb the nutrients from our food. It supports elimination, detoxification, immune system and reproductive function.
We receive a rush of happy hormones, and this lifts our mood helping us to relax further. This relaxation helps us to conserve energy. When we reach this level of calm, it allows the mind to free space for creativity, new ideas and reflection.
This is the side of the nervous system most of us find difficult to support. The main point is downtime and time away from work. Meditation, breathing exercises, yoga, time spent out in nature, massage, hot bath, proper nutrition, cultivating gratitude, all of these can be difficult to give time to in a demanding world that moves 24/7 and 365!
I need to add; some folk can be parasympathetic dominant; for example, is where there is not enough thyroid hormone which can present as depression, lethargy and lack of zest for life.
In order to live a happy, healthy life, we need a balance of the PNS & SNS. We can support this by eating healthy balanced food choices, along with a good balance of weekly exercise and allowing ourselves to get rest and downtime.
All of which we can choose to do to restore harmony to ourselves, or we can continue to burn the candle at both ends and hope for the best.