Have you ever felt rejuvenated and reset after going for a bush walk? Have you ever felt a calmness and inner glow after spending a night camping in untouched forest? Have you ever felt a sense of well being and awe when you stroll through at a biodiverse wildlife garden? Research is beginning to show that there is in fact a genuine reason for these feelings which have genuine benefits for the human body.
While there are obvious benefits in spending time in nature, such as clean air for the lungs, allowing your eyes to adjust to longer distances, and physically engaging your muscles, there are other more subtle but also more potent ways immersing in nature improves your health. It’s all to do with how your brain chemistry works, and in particular, how the stress hormone cortisol works.
For those of you who aren’t familiar with cortisol, it’s a hormone which is important for many normal body functions, such as sleep, inflammation and the flight or fight response. However, long term exposure to elevated levels of this hormone can cause weight gain, impaired immune system and can shorten your life. When cortisol levels are spiked in your system, your body is essentially saying “don’t do what ever you just did again”. For example, in stressful situations such as bungee jumping, your cortisol levels will spike. This is a reaction to preserve your life.
Now that we understand the basics of the hormone cortisol, we can have a look at the difference between the brain of someone who lives in the city and someone who lives in nature. Lets look at a hypothetical situation; say you have identical twins which live almost identical lifestyles (i.e. eat the same food, do the same amount of physical activity etc.), but one lives in the Sydney CBD and the other lives in the rural forested areas on a property in Dungog. Disregarding the effects that pollution would have on the twin in the city, the twin that lives in the bush surrounded by nature will be expected to live longer.
Why? The answer is due to cortisol. The body of the twin in the city has long term elevated levels of cortisol that then the twin in the bush. The reason the cortisol is so elevated in the twin in the city (once again disregarding factors such as noise pollution and alter sleeping regimes), is due to simply looking at the city. Evolution has devoured genes which give us positive neurochemicals when we are in biodiverse bushland with lots of different animals and plants, and in contrast, give us negative neurochemicals, such as cortisol, when we are not in biodiverse areas. This is so that it will force us to seek out areas of plentiful resources.
Now of course cities have plentiful resources, in fact they have more resources at our fingertips than any other place. However, you have to understand that our brains and bodies have not caught up to modern technology and cities. Evolution of humans has taken place over hundreds thousands of years and cities have only been around for a couple hundred, or a couple if you count civilisations such as Rome and Egypt. To achieve a higher level of health the every day human MUST immerse in nature regularly. This leaves us with two options to gain maximum health benefits from nature.
The two options are: Go on weekly adventures into the bush, or if you have a tight schedule and are generally too busy to make this commitment, bring biodiversity back into your living space (visit the Backyard Conservation project to learn more). Either way doing one or both of these will enable you to control cortisol levels and enable your body to stop worrying. Some experts even suggest spending a whole weekend on a camping or hiking trip in the bush as this amount of time can reset your sleeping cycles and bring you back to natural cortisol levels. Please share this post and spread the word so that we can all achieve greener cities and ultimately, better health.