One study found that staying in nature is associated with a significant drop in stress hormone levels.
Interestingly, 20-30 minutes outdoors seems to be the ideal time to take advantage of reduced cortisol levels.
Can't you go outside? Another study found that looking at pictures of nature offers similar cognitive advantages as walking in nature.
Research on how nature reduces stress
On some days, nothing seems to be going right. There can be many small things adding up or one important thing that bothers you, such as paying bills, arguing with your significant other, or worrying about a health problem. Whatever the cause, it is important to recognize when you are stunned and to do something to reduce your stress. And achieving this relief could be easier than you think. According to recent research, it can only take a little time in nature.
The study, conducted at the University of Michigan at Ann Arbor, found that a 20 minute or more stay in nature is associated with a significant drop in stress hormone levels. These results are based on a study involving 36 men and women with an average age of almost 46 years, all of whom lived in urban areas.
Within eight weeks, the subjects were asked to visit an outdoor environment in which they felt that they were encountering nature. They chose the locations themselves and decided when they wanted to adhere to the guidelines that it should be at least 10 minutes per visit three times a week throughout the duration of the study. The volunteers have been prevented from engaging in certain activities that may affect their stress while in their nature, including exercise, talking to others, reading and, I must say, using their cell phones.
At four random times, the researchers collected samples of participants' saliva both before and after one of the nature sessions. The cortisol level – the stress hormone "fight or flight" released by the adrenal glands – was measured and reduced by an average of 21.3 percent per hour after interaction with nature.
The amount of time you need in nature
Interestingly, 20-30 minutes outdoors seems to be the ideal time to take advantage of reduced cortisol levels. Longer periods in nature remained beneficial for the subjects, but the decrease in cortisol was less. The researchers also checked alpha-amylase levels, an enzyme in saliva that is known to be a reliable biomarker for stress levels. They discovered that those who chose to just sit at their natural site or do a combination of sitting and walking had a 28 percent hourly reduction in alpha amylase.
This study is obviously limited by the very small size of its population sample, which makes it difficult to say whether the results could be replicated in a larger, more diverse group. Nevertheless, the results appear to be largely consistent with those of other similar research. For example, a 2010 study at the University of Essex in the UK showed that just five minutes of exercise in a natural setting improves mental health.
And it would certainly not do us any harm to communicate a little more with nature. We should "stop and smell the roses" for a reason. It is healthy for us to spend a little time outdoors in the sunshine and fresh air and to admire the beauty of the vast natural world that surrounds us. People living in urban environments may benefit more because this is not a typical environment. So it is good to find a nearby park or garden where you can spend time in nature. Suburbs and rural residents may not have to put in as much effort, but should reserve some time throughout the week to take a stroll through the neighborhood, or at least sit on the porch or in the back yard and enjoy the bounty of nature without a cell phone your hand.
Photos of nature also an advantage
If you're having trouble getting to a natural site on a regular basis, a mural of a natural scene or pictures of flowers as a screen saver may be the next best thing. No joke. A 2008 study at the University of Michigan at Ann Arbor found that viewing nature pictures offered similar cognitive benefits as walking in nature.