Nature And The Brain
Contributed by Jenni Cutts

Nature And The Brain - How Going Outside Can Improve Your Mind

We spend way, way too much time indoors. There are reasons for that – work, weather, the prevalence of cars, the lack of green spaces in our cities etc etc. However, there is considerable evidence to suggest that making the effort to head outside can be more than worth it. Not only do you get all the oft-touted benefits of increased physical fitness and robustness, but the simple act of heading into the outdoors can also have an unparalleled effect upon your mental state. The outdoors has been proven in numerous scientific studies to have a really quite incredible impact upon our moods, rendering us happier, soothing away our stresses, and even improving our cognitive abilities. Don’t believe us? Read on…

A Basic Human Need

The popularity of relaxant drugs like cannabis would appear to indicate that humanity desperately desires a way in which to bring calming pleasure and happiness into lives. point out that cannabis use can cause “euphoria and relaxation” [1] - and the statistics of cannabis usage worldwide indicate that these are feelings which humanity clearly deems highly desirable. The World Health Organization state unequivocally that cannabis is the most widely consumed drug worldwide – barring alcohol and caffeine. “About 147 million people, 2.5% of the world population, consume cannabis (annual prevalence) compared with 0.2% consuming cocaine and 0.2% consuming opiates” [2]. Given that, in many states and nations, cannabis is both illegal and expensive, the need for such feelings of relaxed pleasure must be intense. Otherwise, individuals would not spend their hard earned money and risk arrest in order to obtain them artificially through the consumption of cannabis. However, there is strong scientific evidence to suggest that equivalent feelings can be obtained safely, legally, and for free – simply by going outside and engaging with the natural world.

Evolutionary Design

Few would argue that going outside can be a real mood boost. However, few realize just how potent this mood boost really is. Far from simply making you feel a little bit happier (perhaps through distraction or the feeling of ‘doing something’), fundamental aspects of the outdoor world can positively alter your brain chemistry and bring it into the kind of prime operating mode for which evolution has designed it. It must be remembered that for the vast majority of humanity’s existence, the species has been spending its time almost exclusively outdoors, retreating to shelter only during times of sleep and sickness. As such, our bodies and brains have evolved to work with outdoor conditions, and are naturally rather flummoxed by the modern tendency to coop ourselves up in artificial indoor environments. Here are just a few of the ways in which your brain can use the outdoor conditions to improve the way it works and make you feel happy:


Harvard University point out that “Light tends to elevate people’s mood, and there’s usually more light available outside than in” [3]. Artificial light in this case does not cut the mustard – but natural light appears to have this mood-lifting effect whether it’s the frosty light of a winter’s morning or full summer sunshine. Why? Well, it probably has a lot to do with a wonderful neurotransmitter called serotonin. Serotonin has a key role to play in regulating the body’s circadian rhythms. It helps our brains to work out when they should wake up, when they should eat, when they should sleep and so on. Serotonin production is stimulated when there is an abundance of natural light – this is the mechanism by which our brains know to wake up naturally at dawn and increase activity as it gets lighter. As well as its role in regulating our natural rhythms, however, serotonin also has a major part to play in regulating our moods. For this reason it is known as the ‘happiness hormone’. Researchers at Bethesda agree that depressive conditions “suggest a trait abnormality of serotonin function” [4], and serotonin is used with great success to treat such conditions. Clearly this is a very powerful neurotransmitter, capable of bringing about major mood and behavioral change. Going outside increases the brain’s levels of serotonin completely naturally, making you feel wonderful whatever the weather!


Vitamin D is not a difficult vitamin to obtain, and it is a sad measure of the modern Western lifestyle that, as Walgreens say, “many people are deficient in this nutrient” [5]. It is absorbed through the skin from sunlight, and plays a host of important roles in the body – including aiding calcium uptake and thus promoting healthy skeletal function. However, vitamin D deficiency has also been associated with poor moods and low cognitive abilities in adults. A study conducted by Conseulo H Wilikins MD and colleagues discovered that “Vitamin D deficiency was associated with presence of an active mood disorder” [6]. Wilikins further noted that “Depression and seasonal affective disorders have been improved with vitamin D supplementation and ultraviolet light exposure” [7], although she did speculate that the concurrent depression occurring with vitamin D deficiency may also something to do with the typical lifestyle of a seriously depressed person (who may not venture outside a great deal). Other studies, however, have obtained similar results. Pamela Murphy and Carol Wagner (both MDs) researched vitamin D deficiency and mood disorders in women, discovering that “four of…six studies (each examining a different mood disorder) show a significant association between mood disorders and low vitamin D levels” [8]. The reasons behind this are disputed – but a likely scenario holds that vitamin D receptors help to regulate glucocortoid signaling. This is complex science, and the theory is in its infancy but, put simply, disrupted glucocortoid signaling has been observed to cause major depressive syndrome in lab animals. Whatever the science behind it, however, the evidence is becoming increasingly clear – vitamin D is good for your moods, and it is best obtained by going outside and getting the sun on your skin.


In his book ‘Last Child in the Woods’, author Richard Louv correlates the decline in outdoor activities for children with the growth in “some of the most disturbing childhood trends, such as rises in obesity, Attention Deficit Disorder (ADD), and depression” [9]. This may seem dubious to some, but in fact Louv’s assertions are well supported by research. A 2008 study into children with Attention-Deficit Hyperactive Disorder (ADHD) found that “Natural environments may improve attention”, possibly because “Nature [can]…effortlessly engage the human mind away from daily stressors, offering an opportunity for reflection and escape” [10]. Essentially, it soothes and refreshes the mind, rendering it capable of returning to a given task with renewed vigor and concentration. This effect was particularly noticeable in children with ADHD, but it applies to everyone. Nature is great for beating mental fatigue, and can give your brain an all-round boost. So what are you waiting for? Head outdoors and enjoy yourself!

[1], "Classifications, uses and effects"

[2] Management of Substance Abuse, "Management of Substance Abuse: Cannabis", World Health Organization

[3] Harvard Health Publications, "Spending time outdoors is good for you, from the Harvard Health Letter", Harvard Medical School, July 2010

[4] National Institute for Mental Health's Mood and Anxiety Disorders Program, "Tryptophan depletion, serotonin, and depression: where do we stand?", Bethesda, 2003

[5] Walgreens, "Vitamin D Supplements"

[6] Conseuelo H. Wilikins, Yvette I. Sheline, Catherine M. Roe, Stanley J. Birge, John C. Morris,  "Vitamin D Deficiency Is Associated With Low Mood and Worse Cognitive Performance in Older Adults", December 2006

[7] Ibid

[8] Pamela K. Murphy, Carol L. Wagner, "Vitamin D and Mood Disorders Among Women", Journal of Midwifery and Womens Health, 2008

[9] Richard Louv, "Last Child in the Woods", Algonquin Books

[10] Leyla E McCurdy, Kate E Winterbottom, Suril S Mehta, James R Roberts, "Using Nature and Outdoor Activity to Improve Childrens' Health", May 2010