Here at The Conservation Foundation we are committed to preserving natural areas and cleaning up our waterways for the good of the plants, wildlife and environment in our area. But the other good part of preserving nature is that it is good for Homo sapiens, too. In addition to anecdotal evidence of the benefits of nature – who doesn’t feel better after a walk outside on a beautiful spring day? - there have been plenty of research studies that confirm what most people innately feel.
For example, a University of Michigan study in 2014 showed that depression and stress are reduced when walking outside with others and indeed had lasting effects for improving people’s mental outlook. Another study published in the journal, Psychological Science, reported on the “The Cognitive Benefits of Interacting with Nature” . Activities outside in natural areas don’t require the direct attention that is required in an urban environment with all its noisy stimuli, so the brain is able to rest. After spending time outside, focusing one’s attention on projects or problems is easier.
A number of studies indicate substantial benefits to children who spend time playing outdoors in natural settings. Nature appears to be a noticeable benefit to children with ADD/ADHD. To quote from a study abstract by Andrea Fabor Taylor and Frances E. Kuo at the University of Illinois:
Findings suggest that everyday play settings make a difference in overall symptom severity in children with ADHD. Specifically, children with ADHD who play regularly in green play settings have milder symptoms than children who play in built outdoor and indoor settings. This is true for all income groups and for both boys and girls. 
Just as more and more people are seeing the benefits of preserving natural areas and adding native plants to our urban/suburban landscapes for wildlife, people are becoming aware of the restorative health benefits of the natural world for people. Richard Louv has written a number of books about nature, family and community and has brought considerable attention to this issue. In his book, Last Child in the Woods: Saving Our Children from Nature-Deficit Disorder, he describes the disconnect from nature that too many children have these days. However, the benefit of nature is not a new idea. Historically, people have realized how gardening, walking in the woods and digging in the dirt are good for our health. Louv references Chinese Taoists who built gardens and greenhouses to improve their health over two thousand years ago.
A particularly interesting study came out of Japan in 2009 At the Nippon Medical School, the researchers found that spending time in the woods strengthens our immunity. As it happens, plants give off volatile organic compounds called phytoncides to protect themselves from insects. When we are in the woods, we breathe in these phytoncides along with their antibacterial and antifungal qualities. The result is that the number of natural killer (NK) cells in our bodies is increased. NK cells provide rapid responses to viral-infected cells as well as to tumors. The Japanese Ministry of Agriculture, Forestry and Fisheries encourages citizens to visit forests and even created a new word, ‘‘shinrin-yoku’’, which means forest bathing.
In DuPage County the forest preserve district has the same idea. In August and September they sponsored a “Forest Fitness Walk” series led by a ranger and naturalist. However, we don’t have to limit ourselves to planned walks, just take a quick detour during your day or week to get to your local natural area and spend 15-20 minutes getting some Vitamin D (crucial for many body functions) from the sun, feeling the breeze on your skin and inhaling those healthy substances from the forests, wetlands and prairies around you. That’s a prescription that puts a smile on my face.
By Nancy Cinatl, firstname.lastname@example.org, Conservation@Home Asssisten
 Source: Marselle M, Irvine K, Warber Sara. Examining Group Walks in Nature and Multiple Aspects of Well-Being: A Large-Scale Study. . 2014.
 The Cognitive Benefits of Interacting With Nature Marc G. Berman,1,2 John Jonides,1 and Stephen Kaplan1,3 1 Department of Psychology, 2 Department of Industrial and Operations Engineering, and 3 Department of Electrical Engineering and Computer Science, University of Michigan
 Faber Taylor, A. and Kuo, F. E. (2011), Could Exposure to Everyday Green Spaces Help Treat ADHD? Evidence from Children's Play Settings. Applied Psychology: Health and Well-Being, 3: 281–303. doi:10.1111/j.1758-0854.2011.01052.x
 Louv, Richard. (2005) Last child in the woods :saving our children from nature-deficit disorder Chapel Hill, NC : Algonquin Books of Chapel Hill
Environ Health Prev Med. 2010 Jan;15(1):9-17. doi: 10.1007/s12199-008-0068-3. Effect of forest bathing trips on human immune function.