3 Ways Nature may Protect our Brains against Dementia

We all know the joys of being out in nature. The sights, sounds, smells and fresh air are great for our state of mind. Research has even shown that simply being able to see nature from inside has a positive impact on our well-being.

In fact, the benefits of time spent outdoors may go deeper than merely improving our mental health. "Nature may also help protect against the risk of developing certain neurodegenerative disorders," according to a February article in The Washington Post.

The article was about a study of almost 62 million older adults (age 65 and up) in the U.S. and the time they spent in nature or "green spaces" such as parks or yards. A study in the U.K. showed similar results. Those who lived in an area "with more green space had a lower rate of hospitalization for Parkinson's disease, Alzheimer's disease and related dementias such as vascular dementia and Lewy body dementia." The presence of "blue spaces"—oceans, lakes or rivers—also had an impact, but only on hospitalizations for Parkinson's disease.

The "whys" behind these results are still being researched, but experts believe that one of the biggest reasons is nature's ability to reduce our stress. We have long known that when we're in nature, our bodies increase their production of certain feel-good hormones and other chemicals. This gives us a natural, lasting boost, so getting outside frequently may explain the long-term protection against cognitive decline. Exposure to nature helps us build our resilience.

The author of the study also talked about what's missing from the best green spaces. "In general, air pollution and noise levels are lower in greener environments," said study author Jochem Klompmaker of Harvard University's T.H. Chan School of Public Health. "Some of these mechanisms may be related to Alzheimer's disease and Parkinson's disease."

How else might time outdoors be good for us? Dementia Adventure, a U.K.-based charity, credits the role of being active while outdoors, exposure to fresh air and light, and the opportunity to make lasting pleasant memories. Here's how those three factors might contribute.

Being Active Outdoors

Besides increasing the flow of blood and oxygen to the brain, being active outdoors can:

-Reduce inflammation in the body, which has been linked to cognitive decline and the development of Alzheimer's disease.
-Promote neuroplasticity, the brain's ability to adapt and change in response to new experiences. Outdoor activities that challenge the brain, such as hiking or learning a sport, can promote neuroplasticity and improve cognitive function.
-Increase our intake of vitamin D, which has been linked to a reduced risk of cognitive decline and Alzheimer's disease.

Yes, running 5 miles is one definition of being active outdoors. But people who aren't extremely fit need not worry: Even walking is considered being active. Join a walking or hiking group. If you can do more, so much the better.

Getting Fresh Air and Light

Every parent who takes their child outside knows these benefits. Turns out they work for older people, too.

-Improves mood. Exposure to natural light and fresh air can improve mood and reduce the risk of depression, which has been linked to an increased risk of cognitive decline and Alzheimer's disease.
-Improves sleep. Exposure to natural light can help regulate the body's circadian rhythms and improve sleep, which is important for brain health.
-Stimulates the brain. Being in nature can stimulate the brain and provide new and varied sensory experiences. That, in turn, can promote neuroplasticity, which we can also think of as resilience, and improve cognitive function.

Even on days when you don't leave your home, nature can work for you. Spend some time looking out a window. Seeing lawns, flowers and trees will benefit you. If your front or back door opens to the outside, take a few breaths there.

Creating Lasting Pleasant Memories

More research is needed to fully understand the impact of Alzheimer's on memory. But we do know that happy memories in general contribute to our resilience and mental well-being. For someone at risk of developing Alzheimer's, happy memories may offer these benefits:

-Provides a positive outlook. Focusing on cheerful memories can provide a positive outlook on life, which has been linked to better cognitive function and a reduced risk of developing Alzheimer's disease.
-Increases social engagement. Sharing nice memories is a great way to talk and connect with other people. That has been linked to better cognitive function and a reduced risk of developing Alzheimer's disease.

Many joyful memories are made while we're outside: taking the kids to the park, vacationing at local beaches or national parks, even trick-or-treating. There's no reason the fun—or the memories—have to end. Meet with friends in the backyard or at a park. Take a walking tour next time you're on vacation. And bring the grandkids along!