Life Course Nature Exposure and Mental Health Outcomes: A Systematic Review and Future Directions

Exploring the Restorative Effects of Natural Environments in Virtual Reality

Natural environments are known to foster positive emotions and well-being, while Virtual Reality (VR) represents a powerful tool to explore such effects. This study investigates the restorative potential of virtual natural environments for emotional recovery, combining self-report and physiological measures. Fifty-two participants were divided into three Natural groups-formed spontaneously based on their preferred natural scenarios-and a Neutral group-exposed to a neutral scenario. The results reveal that virtual natural scenarios effectively restored positive emotions (valence) after exposure to arousing stimuli. Both neutral and natural scenarios reduced arousal, but the physiological data show higher activation in Natural groups. Interestingly, this activation was positively appraised, supporting emotional recovery. These findings confirm the restorative potential of VR nature, with nuanced arousal effects.

Does daily nature exposure enhance children's self-worth and positive feelings? An experience sampling study

Previous studies suggest that nature exposure has positive effects on children's cognitive performance and well-being . However, inconsistent evidence was found for effects on children's self-worth and feelings. These inconsistencies may be resolved by studying children's actual exposure and experiences in detail. Therefore, in the present study, we investigated the effect of daily nature exposure on children's self-worth and feelings with an experience sampling method. Sixty-six third graders (29 girls, mean age = 9.04 years) participated two to three times per day consecutively for 9 days. The resulting 1199 observations were analyzed and showed that when exposed to nature children reported significantly higher self-worth and positive feelings than when not exposed to nature, with baseline levels controlled. Positive feelings played mediating roles in relationships between nature exposure and children's self-worth. Our study strengthens the evidence on beneficial effects of nature on children's well-being. The mechanisms involved in this effect are discussed.

Driven by feelings or stimulated by context: how childhood nature experience shaped adulthood pro-environmental behavior?

Introduction

In recent years, China has vigorously promoted sustainable social development, aiming to enhance residents' environmental protection awareness and encourage their active participation in environmental protection through various means. To achieve this goal, cultivating environmental feelings (EF) among residents has become a key initiative. Childhood nature experiences (CNE) may have a profound impact on pro-environmental behaviors (PEB) in adulthood. However, the specific mechanisms underlying this influence remain unclear.

Methods

This study, viewed through the lens of the biophilia hypothesis, uses EF and environmental contacts (EC) as mediating variables, and environmental risk perception (ERP) as a moderating variable. Statistical analyses, including multiple linear regression, mediation, and moderation analyses, were conducted on data from 1,499 survey responses to explore the mechanisms through which CNE influence PEB in adulthood.

Results

(1) The study shows that CNE do not have a direct effect on PEB in adulthood, but instead exert an indirect influence through EF and EC, with the mediating effect of EF being stronger than that of EC. (2) ERP significantly moderates the relationship between EC and two types of PEB, as well as the link between EF and private sphere pro-environmental behaviors (PRIEB). However, it does not significantly moderate the relationship between EF and public sphere pro-environmental behaviors (PUBEB). (3) ERP significantly moderates most of the mediating effects.

Conclusion

The findings suggest that relying solely on childhood EC does not directly shape adult PEB. Compared to EC, EF play a larger mediating role between CNE and adult PEB. ERP strengthens the mediating effects of both EC and EF. The study emphasizes that both unstructured nature contact and planned, educational outdoor activities during childhood are equally important. Society should provide abundant opportunities for nature experiences, cultivate environmental feelings, and establish a close connection with nature to lay the foundation for developing future participants and advocates for environmental protection.

A systematic review of the associations between biodiversity and children's mental health and wellbeing

There is a growing interest in how exposure to biodiversity influences mental health and wellbeing; however, few studies have focused on children. The aim of this review was to identify studies that used components of biodiversity and children's health outcomes to assess if there were any themes that could be used to inform urban design and understand the mechanisms behind associations. We used a PROSPERO registered protocol to identify eligible studies following pre-defined inclusion criteria. After searching five databases, 25 studies were included in the review. From these articles we extracted data on the biodiversity exposure and mental health and wellbeing outcomes. Five categories of biodiversity exposure were identified, including species diversity (n = 1; 4%), functional diversity (n = 6; 26%), ecological community (n = 9; 36%), green space metrics (n = 4; 16%), and high-level classifications (n = 6; 24%). Children's health and wellbeing were tabulated into seven categories: play (n = 10; 40%), wellbeing (n = 6; 24%), mental health and cognitive functioning (n = 5; 20%), attention deficit hyperactivity disorder (ADHD)-related behaviours (n = 4; 16%), preferences for nature (n = 3; 12%), academic achievement (n = 2; 8%), and restoration (n = 2; 8%). The high heterogeneity of biodiversity and health measures reduced our ability to identify relationships across studies and formally test for an exposure-dose response. Future research that uses standardised and transferable biodiversity measurements at multiple scales, has stronger reporting rigour, greater consideration of potential modifiers, and increased representation of studies from the Majority World are essential for building a stronger evidence base to deliver child-centred biodiverse landscapes.

Predictors of Life Satisfaction in Native Hawaiian and Pacific Islander College Students

This study examines predictors of life satisfaction in Native Hawaiian and Pacific Islander (NH/PI) college students, who form an underrepresented group in well-being research. In a sample of 128 NH/PI students from a public university in Hawaii, self-report measures of life satisfaction, affect, stress, and mood were analyzed. The results indicate that positive affect and mood are significant positive predictors for life satisfaction, while negative affect predicts lower satisfaction. By contrast with other racial/ethnic groups, perceived stress did not significantly impact life satisfaction in NH/PI students. These findings suggest that emotional well-being is a key determinant for life satisfaction in NH/PI students, and stress is not. Culturally responsive interventions that focus on positive emotions and community support can enhance well-being and academic success in this population. This study contributes to the understanding of unique cultural influences on well-being in NH/PI students and provides implications for targeted interventions.

Life in green: Associations between greenspace availability and mental health over the lifecourse - A 40-year prospective birth cohort study

BACKGROUND

The beneficial impacts of greenspace availability on mental health are well-documented. However, longitudinal evidence using a spatial lifecourse perspective is rare, leaving the dynamics of how greenspace influences mental health across the lifecourse unclear. This study first uses prospective birth cohort data to examine the associations between greenspace availability in childhood (0-16 years) and mental health in adolescence (16 years) and between greenspace availability and mental health across adulthood (18-40 years).

METHOD

Data were obtained from the Christchurch Health and Development Study, comprised 1,265 cohort members born in Christchurch, New Zealand, in 1977. Mental health outcomes including depressive symptoms, anxiety disorders and suicidal ideation were assessed in adolescence (16 years), and in adulthood (18-40 years). Greenspace availability from birth to age 40 years was measured as the proportion of vegetated areas within circular buffers (radius from 100m to 3000m) around members' geocoded residential addresses using a time-series impervious surfaces data from 1985 to 2015. Bayesian Relevant Lifecourse exposure models examined the associations between childhood greenspace availability and adolescent mental health and tested for critical/sensitive age periods. Generalised Estimating Equation logistic regression models assessed the associations between greenspace availability and mental health across adulthood. These analyses were adjusted for various important individual, family, and area-level covariates.

RESULTS

No associations were found between childhood greenspace availability and any adolescent mental health conditions. However, in adulthood, a one standard deviation increase in greenspace availability within 1500m and 2000m buffers was associated with a 12% and 13% reduced risk of depressive symptoms, respectively, after adjusting for various covariates.

DISCUSSION

This study supports the protective effects of greenspace on adult depressive symptoms, highlighting the significance of employing a spatial lifecourse epidemiology framework to examine the long-term effects of environmental factors on health over the lifecourse.

Effects of forest bathing (Shinrin-yoku) in stressed people

Aim

This study aims to explore the physiological effect of forest bathing on stress management.

Methods

A total of 29 volunteers participated in this pre-post design, which lacked a control group. Several physiological parameters were recorded, including heart rate (HR), heart rate variability (HRV), electrodermal activity (EDA), blood pressure (BP), immunoglobulin A (IGA), and salivary cortisol (sCort). Additionally, the Perceived Stress Scale (PSS-10) was administered before forest exposure. Measurements were taken before and after participants spent 2 days fully immersed in a forest environment. To further assess stress management, participants completed a Mental Arithmetic Task (MAT) before and after forest immersion, during which EDA, HRV, and HR were monitored using an Empatica E4 wristband. Measurements were taken at baseline, during MAT, and afterward (recovery).

Results

Participants exhibited moderate perceived stress levels before forest immersion (mean PSS-10 = 21.22, SD = 3.78). Post-forest exposure, there was a significant decrease in sCort (p < 0.05) and EDA (p < 0.001), while HRV increased (p < 0.001), and diastolic blood pressure rose (p < 0.05). ANOVA results from the MAT showed a significant increase in parasympathetic activity across all conditions post-immersion (p < 0.05), except during recovery, while EDA decreased in all conditions post-forest exposure (p < 0.05).

Conclusion

Shinrin-yoku significantly improved stress management at a physiological level and could be a valuable intervention for individuals experiencing stress. However, longitudinal studies with a control group are necessary to determine whether these effects are sustained over time. Nonetheless, this study highlights the potential benefits of forest immersion for stress reduction by enhancing sympathovagal balance and the adaptability of the stress response system.

Outdoor stays-A basic human need except for older adults in residential care facilities? Researcher-practitioner interaction crosses zones and shows the way out

The aim of this discussion paper is to show the way to the outdoors by shedding light on conditions in the physical environment enabling outdoor stays for older adults living in residential care facilities (RCFs). The origin was that outdoor stays is a basic human need and applies to everyone. However, despite extensive research on the health-promoting values of contact with the outdoors, it seems that for older adults in RCFs this is not met because they often have difficulty getting outdoors on their own. Therefore, the access to and the conditions of outdoor environments are discussed and exemplified through two cases based on evidence-based approaches, namely the principal model of four zones of contact with the outdoors, and the Swedish version of the Sheffield Care Environment Assessment Matrix (S-SCEAM). An interdisciplinary team, including both researchers and practitioners highlights future directions by showing the way to the outdoors on a national level with six suggested points. As a reader, you will gain increased knowledge about environmental qualities that support outdoor stays as well as initiatives that are needed to achieve equal conditions related to outdoor stays in RCFs.

Life course and mental health: a thematic and systematic review

OBJECTIVE

This study explored the influence of the life course on mental health by identifying key trends, seminal works, and themes in existing research. Additionally, it highlights the major discussions at the intersection of life course and mental health.

METHODS

Documents were extracted from the Web of Science Core Collection (WoSCC), to systematically analyze themes on mental health outcomes across the life course. The analysis was based on key bibliometric tools, including VOSviewer 1.6.11, R Studio software, and GraphPad Prism 9 to analyze the evolution and impact of scholarly contributions in this domain.

RESULTS

The accumulated body of research concerning the life course's impact on mental health, which began to emerge around 1990 displayed a consistently upward trend. Predominant contributions originate from developed nations and frequently look into the psychosocial determinants of mental health over life course. Life course and mental health studies have been extensively infused with biopsychosocial frameworks that consider the role of genetic makeup, neurodevelopment, cognition, affect, sociocultural dynamics, and interpersonal relationships. Life course theory application in mental health highlight the substantive effects of accumulated adversities, notably social determinants of health, adverse childhood experiences (ACEs), and their implications for subsequent mental health outcomes.

CONCLUSION

The nexus of life course and mental health outcomes demands further scholarly interrogation, particularly within underserved regions, to strengthen protective mechanisms for vulnerable populations.

Contacts with environmental biodiversity affect human health: links revealed during the initial waves of the COVID-19 pandemic

The gradual decrease in the prevalence of serious infectious diseases over the last century has been followed by increase in so called "modern" diseases, including allergies, chronic inflammatory conditions, psychiatric, and metabolic disorders. Between 2019 and 2022, public awareness of the threat of infectious diseases in humans was renewed by the global pandemic of a new type of a coronavirus, the SARS-COV-2. This public interest opened improved possibilities to test hypotheses on the factors associated with inter-individual variation in susceptibility to infectious and "modern" diseases. Based on the Hygiene hypothesis and Biodiversity hypothesis, we predicted that contacts with natural environment and wildlife in childhood and/or in adulthood can improve general health and decrease the risks of severe COVID-19 progression or prevalence of the "modern" diseases, namely the allergies. Here we report the results of an online, self-evaluating questionnaire survey conducted in the Czech Republic, where we contrasted selected health issues, and linked them to the living environment, including the level of contacts with biodiversity. In a sample of 1188 respondents, we revealed a significant association of time spent in nature or contacts with biodiversity with physical and mental health, or incidence of allergies. This is unlike the COVID-19 progression, which was related to age, physical health, smoking, allergies, and interaction of age with smoking, but not to contacts with the natural environmental diversity. Our findings regarding to physical and mental health and allergies are in agreement with the Biodiversity hypothesis of allergy and, linking human and environmental health, they urge for One Health approach application.

The Health-Related and Learning Performance Effects of Air Pollution and Other Urban-Related Environmental Factors on School-Age Children and Adolescents-A Scoping Review of Systematic Reviews

PURPOSE OF REVIEW

This scoping review aims to assess the impact of air pollution, traffic noise, heat, and green and blue space exposures on the physical and cognitive development of school-age children and adolescents. While existing evidence indicates adverse effects of transport-related exposures on their health, a comprehensive scoping review is necessary to consolidate findings on various urban environmental exposures' effects on children's development.

RECENT FINDINGS

There is consistent evidence on how air pollution negatively affects children's cognitive and respiratory health and learning performance, increasing their susceptibility to diseases in their adult life. Scientific evidence on heat and traffic noise, while less researched, indicates that they negatively affect children's health. On the contrary, green space exposure seems to benefit or mitigate these adverse effects, suggesting a potential strategy to promote children's cognitive and physical development in urban settings. This review underscores the substantial impact of urban exposures on the physical and mental development of children and adolescents. It highlights adverse health effects that can extend into adulthood, affecting academic opportunities and well-being beyond health. While acknowledging the necessity for more research on the mechanisms of air pollution effects and associations with heat and noise exposure, the review advocates prioritizing policy changes and urban planning interventions. This includes minimizing air pollution and traffic noise while enhancing urban vegetation, particularly in school environments, to ensure the healthy development of children and promote lifelong health.

Green Space and Internalizing or Externalizing Symptoms Among Children

Importance

Evidence suggests that living near green space supports mental health, but studies examining the association of green space with early mental health symptoms among children are rare.

Objective

To evaluate the association between residential green space and early internalizing (eg, anxiety and depression) and externalizing (eg, aggression and rule-breaking) symptoms.

Design, Setting, and Participants

Data for this cohort study were drawn from the Environmental Influences on Child Health Outcomes cohort; analysis was conducted from July to October 2023. Children born between 2007 and 2013 with outcome data in early (aged 2-5 years) and/or middle (aged 6-11 years) childhood who resided in 41 states across the US, drawing from clinic, hospital, and community-based cohorts, were included. Cohort sites were eligible if they recruited general population participants and if at least 30 children had outcome and residential address data to measure green space exposure. Nine cohorts with 13 sites met these criteria. Children diagnosed with autism or developmental delay were excluded, and 1 child per family was included.

Exposures

Green space exposure was measured using a biannual (ie, summer and winter) Normalized Difference Vegetation Index, a satellite image-based indicator of vegetation density assigned to monthly residential history from birth to outcome assessment.

Main Outcome and Measures

Child internalizing and externalizing symptoms were assessed using the Child Behavior Checklist for Ages 1½ to 5 or 6 to 18. The association between green space and internalizing and externalizing symptoms was modeled with multivariable linear regression using generalized estimating equations, adjusting for birthing parent educational level, age at delivery, child sex, prematurity, and neighborhood socioeconomic vulnerability. Models were estimated separately for early and middle childhood samples.

Results

Among 2103 children included, 1061 (50.5%) were male; 606 (29.1%) identified as Black, 1094 (52.5%) as White, 248 (11.9%) as multiple races, and 137 (6.6%) as other races. Outcomes were assessed at mean (SD) ages of 4.2 (0.6) years in 1469 children aged 2 to 5 years and 7.8 (1.6) years in 1173 children aged 6 to 11 years. Greater green space exposure was associated with fewer early childhood internalizing symptoms in fully adjusted models (b = -1.29; 95% CI, -1.62 to -0.97). No associations were observed between residential green space and internalizing or externalizing symptoms in middle childhood.

Conclusions and Relevance

In this study of residential green space and children's mental health, the association of green space with fewer internalizing symptoms was observed only in early childhood, suggesting a sensitive period for nature exposure. Policies protecting and promoting access to green space may help alleviate early mental health risk.

A Scoping Review of Urban Planning Decision Support Tools and Processes That Account for the Health, Environment, and Economic Benefits of Trees and Greenspace

Compelling evidence shows that trees and greenspaces positively impact human well-being and the environment and offer economic benefits. Nevertheless, there exists a knowledge gap regarding the extent to which this evidence is efficiently incorporated into existing urban planning decision-making processes. This scoping review identified the extent to which urban planning decision-making frameworks, models, and tools consider the health, environmental, and economic benefits of trees and greenspace. Out of 28 reviewed studies, 11 (39%) reported on frameworks, models, and tools that take into account the health, environmental, and economic dimensions of trees and greenspace. Additionally, seven studies provided comprehensive coverage of at least one of the three key dimensions. However, none of the decision support frameworks, models, or tools comprehensively integrated all three dimensions, with only two tools (7%) scoring above 50% (five or more out of nine) in terms of comprehensiveness. This review highlights the urgent need to incorporate the true economic and monetary values of the health and environmental benefits of trees and greenspace to inform urban development decision making.

Nature-based biopsychosocial resilience: An integrative theoretical framework for research on nature and health

Nature-based solutions including urban forests and wetlands can help communities cope better with climate change and other environmental stressors by enhancing social-ecological resilience. Natural ecosystems, settings, elements and affordances can also help individuals become more personally resilient to a variety of stressors, although the mechanisms underpinning individual-level nature-based resilience, and their relations to social-ecological resilience, are not well articulated. We propose 'nature-based biopsychosocial resilience theory' (NBRT) to address these gaps. Our framework begins by suggesting that individual-level resilience can refer to both: a) a person's set of adaptive resources; and b) the processes by which these resources are deployed. Drawing on existing nature-health perspectives, we argue that nature contact can support individuals build and maintain biological, psychological, and social (i.e. biopsychosocial) resilience-related resources. Together with nature-based social-ecological resilience, these biopsychosocial resilience resources can: i) reduce the risk of various stressors (preventive resilience); ii) enhance adaptive reactions to stressful circumstances (response resilience), and/or iii) facilitate more rapid and/or complete recovery from stress (recovery resilience). Reference to these three resilience processes supports integration across more familiar pathways involving harm reduction, capacity building, and restoration. Evidence in support of the theory, potential interventions to promote nature-based biopsychosocial resilience, and issues that require further consideration are discussed.

Gardening in Childcare Centers: A Randomized Controlled Trial Examining the Effects of a Garden Intervention on Physical Activity among Children Aged 3-5 Years in North Carolina

This study examined the effects of a childcare gardening intervention on children's physical activity (PA). Eligible childcare centers were randomly assigned to: (1) garden intervention (n = 5; year 1); (2) waitlist control (n = 5; control year 1, intervention year 2); or (3) control (n = 5; year 2 only) groups. Across the two-year study, PA was measured for 3 days at four data collection periods using Actigraph GT3X+ accelerometers. The intervention comprised 6 raised fruit and vegetable garden beds and a gardening guide with age-appropriate learning activities. The sample included a total of 321 3-5-year-olds enrolled in childcare centers in Wake County, North Carolina, with n = 293 possessing PA data for at least one time point. The analyses employed repeated measures linear mixed models (SAS v 9.4 PROC MIXED), accounting for clustering of the children within the center and relevant covariates (e.g., cohort, weather, outside days, accelerometer wear). A significant intervention effect was found for MVPA (p < 0.0001) and SED minutes (p = 0.0004), with children at intervention centers acquiring approximately 6 min more MVPA and 14 min less sedentary time each day. The effects were moderated by sex and age, with a stronger impact for boys and the youngest children. The results suggest that childcare gardening has potential as a PA intervention.

The Impact of a Woodland Walk on Body Image: A Field Experiment and an Assessment of Dispositional and Environmental Determinants

Studies have shown that nature exposure is associated with a more positive body image, but field studies remain relatively infrequent. Here, we examine the impact of a woodland walk on an index of state positive body image (i.e., state body appreciation), as well as dispositional and environmental determinants of body image improvements. Eighty-seven Polish women went for a walk in Cygański Las, an ancient woodland, and completed a measure of state body appreciation before and after the walk. As hypothesised, state body appreciation was significantly higher post-walk compared to pre-walk (d = 0.56). Additionally, we found that the trait of self-compassion-but not the traits of connectedness to nature, perceived aesthetic qualities of the woodland, or subjective restoration-was significantly associated with larger improvements in state body appreciation. These results suggest that even relatively brief exposure to nature results in elevated state body appreciation, with the dispositional trait of self-compassion being associated with larger effects.

Long-Term Exposure to Greenspace and Cognitive Function during the Lifespan: A Systematic Review

Recent advances in environmental psychology highlighted the beneficial role of greenspace exposure on cognition. We conducted a systematic review of the available studies on the association of long-term exposure to greenspace and cognitive functions across the lifespan. PRISMA guidelines and the PECOs method were applied to screen for eligible studies. Twenty-five studies from Scopus, PubMed, and PsycINFO met the inclusion criteria. Six studies were longitudinal and nineteen cross-sectional. Fifteen studies focused on schoolchildren, six studies on adults, and four on the elderly. Twenty studies used the NDVI to assess greenspace exposure and the remaining used other indexes. Eight studies employed academic achievement as the outcome, eight studies global cognition, six studies attention/executive functions, and three studies memory. The evidence was inconsistent but suggestive for a beneficial role of greenspace exposure on cognitive functions. Further studies are required, especially among adults and older people, by adopting longitudinal designs.

Climate change and global health: A call to more research and more action

There is increasing understanding, globally, that climate change and increased pollution will have a profound and mostly harmful effect on human health. This review brings together international experts to describe both the direct (such as heat waves) and indirect (such as vector-borne disease incidence) health impacts of climate change. These impacts vary depending on vulnerability (i.e., existing diseases) and the international, economic, political, and environmental context. This unique review also expands on these issues to address a third category of potential longer-term impacts on global health: famine, population dislocation, and environmental justice and education. This scholarly resource explores these issues fully, linking them to global health in urban and rural settings in developed and developing countries. The review finishes with a practical discussion of action that health professionals around the world in our field can yet take.

Developing a model linking self-reported nature exposure and positive body image: A study protocol for the body image in nature survey (BINS)

Exposure to natural environments has been shown to be associated with more positive body image, but much of the existing research is limited to Western European nations and little is known about the robustness of these associations in other national contexts. In this protocol paper, we present a conceptual model of the direct and indirect associations (i.e., via self-compassion, connectedness to nature, and restorative experiences in nature) between nature exposure and body appreciation. This model brings together conceptualisations from existing research, but also extends it in a number of important ways. The model will be tested through the Body Image in Nature Survey (BINS), a researcher-crowdsourced project involving researchers in multiple nations worldwide. Data collection began in December 2020 and is expected to be completed in February 2022. Data will be analysed to examine the extent to which our conceptual model is robust across nations, as well as other sociodemographic characteristics. We will also determine the extent to which key variables included in our survey are invariant across nations and associated with cultural, socioeconomic, and gender-related factors. The BINS will likely have important implications for the development of nature-based interventions to promote healthier body appreciation in diverse national contexts.

Greenspace and human health: An umbrella review

Multiple systematic reviews on greenspace and health outcomes exist, but the overall evidence base remains unclear. Therefore, we performed an umbrella review to collect and appraise all relevant systematic reviews of epidemiological studies on greenness exposure and health. We searched PubMed, Embase, and Web of Science from inception to June 28, 2021, and screened references of relevant articles. Systematic reviews with or without meta-analyses of epidemiological studies that examined the associations of greenness with any health outcome were included. Two independent investigators performed study selection and data extraction. We also evaluated the methodological quality of the included systematic reviews using the “Assessing the Methodological Quality of Systematic Reviews 2” checklist. A total of 40 systematic reviews and meta-analyses were included, of which most were cross-sectional studies conducted in high-income countries. Greenspace exposure was estimated with various objective and subjective parameters. Beneficial associations of greenspace with all-cause and stroke-specific mortality, CVD morbidity, cardiometabolic factors, mental health, low birth weight, physical activity, sleep quality, and urban crime were observed. No consistent associations between greenspace and other health outcomes (e.g., cancers) were observed. Most of the included systematic reviews and meta-analyses had one or more limitations in methodology. Our findings provide supportive evidence regarding the beneficial effects of greenspace exposure on some aspects of human health. However, the credibility of such evidence was compromised by methodological limitations. Better performed systematic reviews and meta-analyses as well as longitudinal designed primary studies are needed to validate this conclusion.

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The evidence concerning greenspace and health outcomes remains unclear

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We performed an umbrella review of 40 systematic reviews on greenspace and health

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Greenspace exposure was estimated with various objective and subjective parameters

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Greenspace was beneficially associated with several aspects of human health

Permanent Supportive Housing Design Characteristics Associated with the Mental Health of Formerly Homeless Adults in the U.S. and Canada: An Integrative Review

The built environment directly and indirectly affects mental health, especially for people transitioning from long-term homelessness to permanent supportive housing (PSH) who often experience co-occurring behavioral health challenges. Despite a rapid increase in PSH availability, little research examines influences of architecture and design within this context. This integrative review synthesized limited research on PSH design in the U.S. and Canada to identify built environment characteristics associated with PSH residents’ mental health, highlight gaps in the literature, and prioritize future research directions. A systematic search for peer-reviewed articles was conducted using nine databases drawing from multiple disciplines including architecture, environmental psychology, interior design, psychology, psychiatry, medicine, and nursing. Seventeen articles met inclusion criteria. Study design, methodology, built environment properties, place attributes, and relevant findings were extracted and iteratively analyzed. Three domains relevant to architecture and design were identified related to home, ontological security, and trauma sensitivity; dwelling unit type, privacy, control, safety, housing quality and location, and access to amenities; and shared common space. Integrative review results emphasize the potential of architecture and design to contribute to improved built environment quality and mental health outcomes among PSH residents. Methodological limitations and directions for future research are also discussed.