People’s increasing disconnect with the natural environment has widespread implications for wellness. Chronic conditions are increasing on a worrying trajectory; pain is exacerbated by stress and this can create the conditions for long term pain. Reducing stress on our bodies, including through nature-based practices, have been proven to reduce chronic pain and consequently provide a transformative effect on our long-term wellbeing.
Why is pain a problem?
Chronic pain is estimated to affect one-quarter of the world’s population, and presents a considerable therapeutic challenge.
In the UK it has been reported that medical costs spent on chronic pain are equivalent to the costs spent on major diseases including cancer, cardiovascular diseases, and diabetes. It is estimated that associated costs due to the loss of work productivity amount to tens of billions of pounds. Pain not only causes significant inconvenience in daily life, interfering with economic and social activities but it can actually shorten it with additional physical and psychological problems. These include anxiety, depression, fatigue, sleep problems, and poorer quality of life which in turn have other, direct health implications.
Medical science is increasingly moving from treating symptoms of disease to uncovering the determinants of mental and physical health. Pain is a cause of ill health in its own right as well as a symptom.
Why do we feel pain at all?
Short term pain sensations evolved to keep us alive – put your hand in the fire and it will burn. Prompting you to swiftly remove your hand and preserve your skin. Short term pain is a temporary unpleasantness to trigger helpful action, at least where survival is concerned. Pain of this nature is not usually ‘treated’ it is managed with painkillers to reduce its sensation in the short term whilst the injury heals.
Longer term pain is more complicated. All pain is felt in the brain and is as much more about how pain is interpreted than the injury. Ongoing pain can have a part to play in aiding recovery by discouraging the use of a healing injury. However, as any neuroscientist will tell you, the brain is a complex organ. Pain receptors that prompt immediate action in the short term can be overwhelmed if the stimulus continues over time. Pain can continue beyond its usefulness.
Chronic pain is identified as lasting longer than three months, this time period can redefine pain even as an injury heals. In some people nerve signals can keep firing after the injury has healed and can even flare in cases where there was no apparent physical damage in the first place. The link between the neuroscience of why we feel pain and physical stimuli are far more complex than we have traditionally thought. Furthermore we know that our mental and emotional health has a direct impact on how quickly we heal and how much pain we feel. Subsequently the treatment of chronic pain as a symptom but also a cause of ill health is much more challenging.
Stress = Pain = Stress ad infinitum
The human body evolved to survive in a very different environment than the one in which it now finds itself. Once again, to stay alive our bodies developed hormonal responses to stress. The sympathetic nervous system reacts to a perceived threat by releasing cortisol and adrenaline which sharpen the senses and give the ability to fight or flight. They temporarily limit some body functions (digestion, pain sensations) in order to promote others which are more helpful in that moment. This is a supremely useful reaction to run away from a sabretooth tiger.
Being in a heightened state of stress is familiar in modern living. In a life that includes a difficult commute, an artificial work environment ridden with conflict, underpinned by financial stresses and societal expectations, recurrent fight or flight responses have become the norm. Those helpful temporary reactions to save our lives can damage the body and even reduce life expectancy. Increased heart rate to run fast in the moment, leads to high blood pressure and arterial damage over time. Elevated cortisol levels can lead to increased fat storage and increased appetite to ensure that the body has enough energy stores in future. This sounds like a recipe for a heart attack.
Crucially the chronic stress built up over time interacts with chronic pain and each can make the other worse. Feeling physically and mentally stressed can lower the tolerance of pain. Conversely pain is a proven strong risk factor for mental ill health. This downward spiral of pain and stress and mental ill health is visible in friends, family and colleagues all around us. The opposite of this can also be true, reducing stress, can reduce pain, and of course reducing pain will reduce stress.
As chronic pain is more widely understood we are starting to move beyond its treatment as just a symptom. In many cases sufferers of chronic pain are unlikely to recover only through a surgical intervention or pharmaceutical management of symptoms. These interventions, whilst absolutely appropriate in some cases, are definitely not in all and may have significant side effects including addiction to prescription medication. Addiction to prescription medication is reaching epidemic proportions.
Other treatments for pain have included psychological understanding, counselling, exercise as well as complementary and alternative medicine. Psychological interventions are shown to be effective in reducing pain and its comorbid psychological problems. This is particularly helpful in conjunction with physical activity to enable an individual to gain a sense of control and to alleviate tension in the nervous system.
How can Nature relieve pain and stress?
Going back to those stress hormones, the parasympathetic nervous system works in tandem with the sympathetic nervous system. Like two parts of a muscle – contraction and relaxation, the sympathetic nervous system prepares for immediate action whereas the parasympathetic nervous system slows down the body to repair and heal. When the two parts work in balance the body is effective.
So if we know that modern life overstimulates the sympathetic nervous system what then do we do to actively encourage the parasympathetic nervous system and balance our neurotransmitters? The answer is surprisingly simple: relax more, especially in nature. This is of course not as easily done as said. This is where forest bathing can be a positive intervention.
Forest therapies, including Shinrin-yoku, utilize psychological approaches and appropriate physical activities in a natural environment, that can improve pain and comorbid psychological complications. Forest therapies have shown to be effective in providing physical relaxation, soothing anxiety, and relieving depression symptoms as well as activating the parasympathetic nervous system. They have also been shown to have positive effects on neurocognitive functioning and emotion.
Simply smelling trees can help activate your parasympathetic nervous system. Olfactory stimulation from phytoncides (chemicals given off by trees) significantly reduce stress, fatigue, lowers blood pressure and can even help fight cancer! Microbes in soil can help reduce depression, scientists think that this is because bacteria stimulates the immune system and a boosted immune system makes you feel happy.
An increasing number of studies are providing evidence for the effectiveness of forest therapy in various psychological and physical symptoms. With continued publications of such studies, forest therapy has gained increasing recognition as an intervention method based on scientific evidence.
There is currently a clinical trial underway at Cornell University looking at ‘Nature as a Buffer Among People With Chronic Pain’ which is due to conclude next month. We will be excited to hear of the preliminary findings. [https://clinicaltrials.gov/ct2/show/NCT03153891]
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