The Impact of Shrinking Green Spaces on Mental Health: A Scoping Review Across High- and Low-Income Countries

Green spaces are increasingly recognized for their significant contributions to mental health and psychological well-being. While existing literature primarily emphasizes the environmental and ecological functions of green areas, there is a growing body of evidence highlighting their relevance to public health. Despite this, urban and forested green spaces continue to decline due to anthropogenic pressures and insufficient policy implementation. This scoping review investigates the effects of shrinking green spaces on mental health outcomes in both high- and low-income countries. A systematic literature search was conducted using PubMed, Elsevier, and MDPI databases, supplemented by relevant bibliographic references. Studies were selected based on predefined eligibility criteria and evaluated through a structured data charting process. Thematic analytic induction was employed to analyse and synthesize findings into key themes. Thirty peer-reviewed studies met the inclusion criteria, encompassing a range of methodologies. The findings demonstrate a consistent association between green space reduction and adverse mental health outcomes. Notably, the review identifies critical contributing factors to green space loss, including weak policy frameworks, unregulated urbanization, and socio-environmental inequalities. These determinants underscore the urgency of developing integrated strategies that preserve and expand green infrastructure. This review reinforces the premise that diminishing access to green environments constitutes a substantial risk factor for declining mental well-being. Addressing this issue requires a multidisciplinary approach that incorporates inclusive urban planning, equitable policy development, and community-driven environmental stewardship. Ultimately, safeguarding green spaces may serve as a viable intervention to mitigate mental health disparities and promote sustainable development in both urban and rural settings.