The Impact of Residential Greenness on Cognitive Health

A recent review in Nutrients reveals how residential greenness may play a vital role in preventing cognitive decline and dementia, including Alzheimer's disease.

Studies suggest that exposure to greenery can enhance cognitive function through stress reduction, better attention, lower air pollution, increased physical activity, and social connection. However, many studies have been cross-sectional, lacking long-term data.

The Nurses' Health Study (NHS), initiated in 1976, involved 121,700 female nurses. Researchers analyzed data from women aged 70+ without stroke history, assessing cognitive function and greenness exposure.

Higher midlife greenness exposure was linked to better baseline cognitive function and slower cognitive decline. Women in greener areas had higher cognitive scores, suggesting greenness can slow cognitive aging by up to eight months.

Results indicated that mental health partially mediated these benefits. Associations were stronger in low SES and high-density neighborhoods, and among those with the APOE-ɛ4 allele, a genetic risk factor for Alzheimer's.

This study underscores the potential of greenness as a modifiable factor in reducing dementia risk, particularly for those with higher genetic risk and in disadvantaged communities. Further research is needed to confirm these findings and develop targeted interventions.

Source: Marcia Pescador Jimenez , Maude Wagner, Francine Laden, et al. (2024) Midlife Residential Greenness and Late-Life Cognitive Decline among Nurses' Health Study Participants, EHP.