Where you live can reduce your risk of cognitive decline.
As the years go by, the signs of cognitive decline increase. Cognitive decline is the progressive decline in mental abilities. This can include frequent forgetfulness, difficulty concentrating, language problems, and confusion when making decisions. While it is a normal part of aging, cognitive decline can also be a sign of more serious disorders, such as Alzheimer’s disease or other forms of dementia. Researchers at the Boston University of Public Health wanted to know if there was a link between several parameters, including place of residence, and the risk of cognitive decline.
In their study published in the journal “Environmental Health Perspectives”the scientists analyzed data from 16,962 American nurses aged 70 and older, who were followed between 1995 and 2008. They measured all of these women’s exposure to green spaces, using a tool called the “Normalized Vegetation Index.” Based on satellite images, this tool made it possible to estimate the amount of vegetation around the participants’ living spaces. The latter also took several series of cognitive tests by telephone. Other factors taken into account in the data analysis: age, level of education, socioeconomic status of the living space, potential experiences of depression (and use of antidepressants), body mass index (BMI) and air pollution.
According to the researchers, where you live is closely linked to cognitive decline. They found that higher exposure to greenery in midlife was associated with improved mental and physical health and therefore a slowdown in cognitive decline later in life (a decline of 8 months over a year). In women who carry the APOE-ɛ4 gene (a gene that 25% of the population have and which increases the risk of developing Alzheimer’s disease), this slowdown was even more marked, with a slowdown in cognitive decline that was 3 times greater.
“This study suggests that high residential greenness in middle age may provide protective benefits for maintaining cognitive function and preventing cognitive decline later in life.“, shares Marcia Pescador Jimenez, lead author of the study. “Our results are important because they highlight the cognitive benefits of increased exposure to green spaces at the population level, particularly among vulnerable population subgroups, such as APOE-ɛ4 gene carriers.”According to her, improving the environment of low socio-economic status neighborhoods, by providing them with access to green spaces, could be a solution to improve cognitive health and reduce health inequalities.
Direct access to Nature reduces stress, anxiety and helps minimize symptoms of depression. Greenery also encourages people to go outside, walk and exercise, which is beneficial for brain health. Finally, green spaces promote social interactions, which are conducive to emotional and cognitive well-being.