In recent years, numerous studies have highlighted the positive impact of green spaces on overall health. Notably, two studies published in 2022 have specifically examined how green spaces can aid in improving cognitive function, potentially protecting against dementia.
A study published in JAMA Network Open found that increasing green space in residential areas could help improve cognitive function in middle-aged women. Areas with more green space were associated with faster thinking, better attention, and higher overall cognitive function in this demographic. These findings are significant because cognitive function in middle age can predict whether a person develops dementia later in life.
Another study, published in BMC Public Health, focused on older adults and found that neighborhood green space exposure serves as a protective factor against dementia risk among U.S. adults aged 75 years or older. This study provided evidence of an association between residential green space and dementia, with moderate cognitive health benefits observed in older adults.
These research findings are exciting, as dementia is a major area of concern in the medical community. According to Alzheimer’s Disease International, there were over 55 million people worldwide living with dementia in 2020. This number is projected to almost double every 20 years, reaching 78 million in 2030 and 139 million in 2050. The rapidly increasing number of people with dementia highlights the importance of dementia research. Learning more about how our environment impacts dementia can lead to prevention strategies that can significantly affect many lives. For example, green spaces could be implemented in senior living homes as a way to protect against dementia. Green space exposure could even be investigated as a potential population-level approach to enhancing cognitive function nationwide, influencing urban planning, and informing policy decisions regarding green spaces in general residential areas.
However, it is widely agreed that we need more research into this field. While the initial research is incredibly promising, there is still a lot we don’t know.
For example, the exact mechanisms by which green spaces exert their positive effects on cognitive health are still not fully understood. While green spaces often correlate with increased physical activity, reduced pollution, and higher socioeconomic status, which could explain some of the benefits of green space, the benefits of green space persist even when these factors are fully accounted for. The leading theory suggests that nature helps people recover from psychological stress and encourages social interaction, both of which can reduce depressive symptoms. Since depression is a known risk factor for dementia, this might partly explain the beneficial association between green space exposure and cognitive health. However, more research is needed to make conclusive statements.
Current research also has several limitations. Most studies have predominantly focused on white populations, leaving gaps in understanding how the benefits of green spaces might vary across different races and ethnicities. Furthermore, the specific types of green spaces that are most beneficial—whether it be trees, flowers, or grass—remain under-researched. Additionally, the type and level of interaction needed with green spaces to derive benefits (gardening, walking outside, keeping indoor plants, or looking at photographs of nature) is not well known.
As the body of evidence regarding the benefits of green spaces grows, it underscores the importance of green spaces in promoting cognitive health and potentially mitigating dementia risk. Future research will continue to uncover the specific elements of green spaces that are most beneficial and how best to incorporate these findings into individual people’s lives as well as broader public health strategies.
What we do know now is that nature and green spaces show positive links to improving mental and cognitive health. Therefore, there is no harm in attempting to interact with nature more, especially for older adults.
References
[1] Living in Areas with More Greenery May Boost Cognitive Function
[2] JAMA Network Open: Green Space and Cognitive Function
[3] NIA: Exposure to Green Space May Boost Cognitive Health
[4] BMC Public Health: Green Space and Dementia Risk
[5] Alzheimer’s Disease International: Dementia Statistics
