Introduction and Framework
Overwhelmingly, evidence shows that health is directly correlated with the environment. Indeed, the World Health Organization has long defined health as more than the absence of disease,1 yet more recently, other organizations have emphasized the impact of the physical environment on health. In fact, the US Department of Health and Human Services Secretary’s Advisory Committee has adopted a place-based approach recognizing the physical environment, both natural and built, as a key influence on health.2,3 It is thus imperative for integrative medicine practitioners to incorporate information about optimal environments in their toolkits for disease prevention.
Despite this emphasis on the importance of place and the environment on health, a 2014 market report, based on a national survey, suggests that less than half of medical professionals are aware of the impact of the built environment on health, and only 15% reported receiving information on design and health connections.4 This is in contrast to a large majority of design professionals’ awareness of this connection.4 Responding to the challenge to increase awareness of health-environment connections among health professionals and the general public, the design and construction communities aim to connect with medical partners to increase the research and evidence communicated to health professionals, and to make more explicit the alignment between the environment and top rated health risk factors such as obesity and chronic stress.
Among the first attempts to characterize interactions between people and environment was Kurt Lewin’s force field analysis, which describes behavior as the function of the individual and the environment.5 However, Lewin’s “environment” was a social environment and abstract in the physical sense. Soon after, the neuropsychologist Donald Hebb noted behavioral improvements in laboratory rats that were taken home as pets to more enriched environments.6 Over the following decades, several studies reported various characteristics of neurological plasticity resulting from environmental stimulation.7 More recently, the discovery of adult neurogenesis has revealed that the physical environment continually shapes brain structure and function. Indeed, animal studies indicate that enriched environments are correlated with improved cognitive performance.7 The latter finding may in part be related to increased activity, and therefore greater physical exercise, of animals placed in enriched environments. These discoveries advanced place-based research on cognition and performance by providing animal models to triangulate relationships between brain, body, and environment.
Evidence-based design (EBD), one means of improving health impacts through the built environment, emerged over the last two decades, drawing on the tradition of evidence-based medicine. In this chapter, we use an EBD approach to describe key linkages, distilled from current research, between health and the physical environment that are most relevant to providing an environment-based health context for clinical practitioners. This material is organized according to the six key areas correlating health and design defined by the American Institute of Architects (AIA): environmental quality, natural systems, sensory environments, physical activity, safety, and social connectedness.8 Recognizing that the physical environment is interconnected with other determinants of health,3 this chapter is meant to augment the material provided by other integrative preventive practices defined in this volume.
Importantly, the following sections are not intended to serve as an exhaustive review of the related literature but rather as a snapshot of some of the seminal work as well as some key recent developments. The former would be beyond the scope of this chapter; it is important to note that each section has an associated literature that is quickly growing both in depth and breadth, each with its own implications for recommendations impacting health and well-being.
Since the initial epidemiological connection between health and the environment in John Snow’s mapping of the water supply and the cholera outbreak in England in 1854,9,10 the study and regulation of health risks and hazards of the environment have notably expanded to air quality. In fact, when associating connections between health and the environment, medical professionals reported the greatest familiarity with the category of environmental quality concerns relating to acute illness factors such as mold and air pollution.4 Increased urbanization has led to concentrated and increased risk factors for health risks associated with air pollution from motor vehicles, electricity generation, and industrial pollution, and may account for the deaths of approximately 1.2 million people worldwide each year due to cardiovascular and respiratory diseases.11 In recent decades, inner cities have been particularly affected with rising asthma rates, especially among children, the cause of which is unknown but could be related to higher amounts of cockroach dust exposure in those areas.12
Toxins in the air (in addition to those in water, soil, and food) have a disproportionately high effect on children as, pound for pound, they breathe more air than adults, are less able to deal with toxins, have more disruptable physiological systems due to growth and development, and have more years of life remaining to develop chronic diseases.13
Indoor air quality can affect health and well-being just as outdoor air quality can. Humans are an increasingly indoor species, with the developed world spending over 90% of their time indoors.14 Though the regulatory mechanisms for indoor environmental quality (IEQ) have historically focused on avoiding dangerous levels of certain air quality characteristics, environmental quality has the potential not only to prevent illness and disease but also to optimize wellness and psychological well-being. Moreover, recent developments in IEQ literature have signaled a change in direction from the study of specific chemical pollutants and particulate matter to the interaction between the individuals inhabiting a space and design factors.15
One commonly measured and monitored chemical in the indoor environment is carbon dioxide (CO2), a good indicator of the performance of ventilation and the occupancy of a controlled space. Building standards define certain levels of CO2 that are known to be harmful to human health, and other levels that are associated with reports of stuffiness and drowsiness. Because ventilation accounts for a large proportion of energy use in buildings, natural ventilation (i.e., operable windows) is often offered as a design solution to save on costs. However, such strategies must be carefully applied with climate in mind, as CO2 levels have been found to readily exceed acceptable levels in seasons when building occupants are unlikely to open windows.16 Green building designs (e.g., low-polluting building materials, sufficient ventilation rates) have been found to be associated with better occupant health outcomes compared to nongreen building designs, but empirical research is lacking.17 One recent experiment manipulated CO2 and volatile organic compound levels, and found that participants exhibited significantly higher performance on an array of cognitive tests under conditions that mirrored green building practices of ventilation compared to nongreen building practices.18 When ventilation rates went beyond the recommended levels for green building operations, decreased concentrations of CO2 were still associated with increased cognitive task performance.18 Similar trends of cognitive performance have also been shown in children during a classroom-setting manipulation of ventilation rates.19 Ventilation rates are typically based on meeting standards while saving on energy costs, but other indirect human costs are relevant, like employee sick leave, absenteeism, and presenteeism. In one study of 40 buildings within a single company, higher rates of sick leave and IEQ complaints were associated with lower levels of outdoor air supply.20
Current advances in personal ventilation technology allow for the increased understanding of how clean air exchange and flow affects human health, well-being, and performance. Personal ventilation directs the flow of clean air to the individual’s breathing zone rather than to the volume of the entire room, and has been associated with increased perceived air quality and both subjective and objective measures of performance, all while being an energy-saving model of building operation.21
The physical, mental, and social benefits associated with a connection with nature are widely documented, and attest to the importance of engaging with nature in everyday lives. The effects of nature have been linked with benefits such as improved attention, cognitive functioning and test scores, reduced stress, improved mood and coping skills, and enhanced immune functioning.22 Children’s contact with nature has also been linked with physical and psychological health as well as social, sensory, and creativity benefits.23 Studies suggest that nature benefits result from both direct contact with nature, such as taking a walk through a park, and passive engagement with nature, such as observing nature through a window. In Roger Ulrich’s seminal study in 1984, postoperative patients in rooms with views of nature (versus those viewing a brick wall) stayed fewer days in the hospital and took significantly less pain medication.24 Similarly Sullivan and Kuo25 showed less violence and improved social interactions in people randomly assigned to apartments with a view of a grove of trees as compared to a brick wall. Many have attributed such overwhelming beneficial effects to the biophilia hypothesis, which proposes that humans have an instinctual attraction to biological and natural elements that support and sustain life.26
With respect to the built environment, biophilic design attempts to capture the therapeutic effects of nature by incorporating natural and biological elements directly, indirectly, or symbolically, which reflects the inherent human affinity for nature.27,28 This includes strategies such as bringing living elements like vegetative facades into buildings and using naturally occurring shapes and patterns such as botanical motifs in building forms or materials. At the neighborhood level, a recent study in an urban setting showed that having a tree density equivalent to 11 more trees in a city block resulted in fewer cardiometabolic conditions, equivalent to the health status of having an increase in annual personal income of $20,000, or being 1.4 years younger.29
Exposure to natural features, such as walks in parks, has been linked with improved performance and restored attention following fatigue.30,31 Studies have shown that indirect exposure to nature for as little as 6 minutes may provide an attention boost equivalent to caffeine, in young and older adults.32 Similarly, children diagnosed with attention deficits experienced improved concentration with results similar to those of a common medication for ADD after a 20-minute walk in a nature-like park setting when compared with walks in downtown and residential neighborhoods.33 Walking in a natural setting versus an urban setting has also been associated with lowered self-reports of rumination and activity in the associated area of the prefrontal cortex.34 Such findings suggest safe, inexpensive implications for including short nature breaks in daily routines and may serve to benefit myriad user groups.
Unfortunately, according to reports from developed countries around the world, active outdoor play and nature exploration are in decline as a result of factors including children’s and parents’ fears about the dangers of playing outside, the lure of indoor recreational activities such as television and computer games, and the loss of natural areas.35,36 This trend is evidenced across rural, suburban, and urban settings as well as across socioeconomic classes. Play in nature is critical to development not only because of the benefits associated with physical activity, but also because it has been associated with increased performance on tests of motor fitness such as balance and agility.37
Improvements in quantitative measures of the stress and immune response have also been associated with nature exposure. A review on nature and immune functioning22 identified several studies with beneficial results from blood tests taken before and after nature walks, compared with urban walks, including an increase in cardioprotective and diabetic factors such as DHEA,38 adiponectin,38 and normalized blood glucose.39 The Japanese practice Shinrin-yoku, or taking in the atmosphere of the forest, has been linked with measures of relaxation and reduced stress such as lower blood pressure, lower pulse rate, and lower concentrations of cortisol.40 Recent studies have established a significant correlation between cortisol levels and self-reports of stress with the quantity of green space in residential areas,41 which suggests that cortisol can be used as a biomarker to measure short-term environmental effects on stress.
The presence of green space is especially important in economically disadvantaged communities where health disparities and related chronic stress are more severe.41 Contact with nature has been shown to be an effective pain management strategy for elderly residents and patients in direct and indirect applications such as gardening,42 natural murals and sounds,43 window views,24 and in-room potted plants.44 Moreover, a meta-analysis of nature and health studies led reviewers to conclude that contact with nature has a positive effect on psychological well-being, including reductions in anger, fatigue, anxiety, and sadness.45
Healthcare providers can promote cognitive, physical, and psychological benefits of contact with nature by routinely asking about a patient’s exposure to nature in patient interviews and by writing nature prescriptions. Medicine–nature collaborations such as the National Environmental Education Foundation’s (NEEF) Rx for Outdoor Activity program have gained momentum in cities such as San Francisco and Washington, DC (DC Parks Rx), by providing a tool that healthcare providers can use to prescribe safe and accessible interactions with nature.
Perhaps the greatest advances in scientific understanding on how the built environment affects human health, well-being, and performance fall under the umbrella of sensation and perception. Visual, auditory, and thermal comfort consistently rank high in studies of complaints about workplace characteristics, and these areas of sensation also represent those that are best studied most frequently, particularly research on lighting conditions.
Among the best-established relationship between light and mood comes from the depression literature. It is firmly established that full spectrum light therapy is highly effective in treating symptoms of seasonal affective disorder—a form of depression related to long periods of exposure to low light levels. Yet there are many other relevant applications to different populations. There is evidence that inpatients with bipolar depression staying in hospital rooms exposed to eastern morning light had significantly shorter hospital stays compared to those with western exposure.46 Patients recovering from elective cervical and lumbar spinal surgery on the more brightly daylit side of another hospital experienced less perceived stress and took less analgesic medication than those in rooms on the more dimly daylit side.47 Likewise, in yet another hospital, female patient stay post heart attack was also shorter in sunnier rooms compared to less daylit rooms.48
Benefits of day-lighting are also seen for nonpatient populations. Residential homes’ exposure to sunlight has been found to be negatively associated with mortality from breast, ovarian, prostate, and colon cancer.49 Likewise, exposing normal, healthy adults to bright light for extended periods of time has been shown to help lower reported levels of anxiety.50 In an office setting in Finland, exposing employees to brighter light during wintertime boosted subjective vitality and reduced depressive symptoms.51 Additionally, effects of lighting can be seen in animal studies. For example, rats in a lab setting showed increased growth of human xenograft breast cancer when subjected to electric light at night.52 This finding contributes to the growing evidence for health and well-being risks in shift workers with artificially compromised circadian rhythms.
Importantly, circadian rhythms are affected by different types of light exposure as well. Shorter-wavelength blue light is most effective at triggering our body’s internal clock, and is therefore important for circadian shifting when we need to adapt to a new sleep schedule. In one recent study, volunteers were prescribed a shift in their sleeping schedule, but only those who received doses of blue light when they woke up each morning, and orange light when before they went to bed in the evening, showed adaptive circadian phase shifting as measured by melatonin levels.53 In another study, patients with Alzheimer’s disease and related dementia showed improved sleep time and efficiency, improved circadian rhythm, and reduced depression and agitation scores when exposed during the daytime to blue light.54 Because blue light is often emitted by electronic devices such as computer and smartphone screens, exposure after dark can be problematic for all populations, including adolescents, who may be even more sensitive.55 Various software products have been recently gaining attention for their ability to filter emitted blue light from computer and smartphone screens.
Often, implementing light manipulation interventions in real-world settings can be difficult because little is known about design factors that contribute to visual discomfort, such as glare. Some evidence suggests that luminance, type of window view, and even the distance of objects in that view all can affect reported discomfort.56 Workers in one large office building were more annoyed with glare in winter months when there was deeper daylight penetration compared to summer months,57 while in another study workers experienced less subjective glare for daylit conditions (without a view) compared with electric lighting. Deeper sunlight penetration has been found to be positively correlated with job satisfaction and general well-being,58 while other research has demonstrated differences in physiological but not subjective outcomes. In one study, workers in renovated areas with increased day-lighting exhibited higher levels of physiological indicators of well-being—heart rate variability and cortisol—at night compared to those in areas with less day-lighting, even though participants’ subjective reports did not differ on mood and stress measures.59 Interestingly, little is known about the immediate effects of light on performance. For example, in one study, light levels were related to frontal activity on an electroencephalogram but not actual performance on a working memory task.60
More is understood about the effects both chronic and acute noise have on subjective performance and other psychological and physiological well-being outcomes. Perhaps because noise is a common source for complaints in work environments, much of what we know about the effects of different acoustic environments comes from applied research in real-life work settings and in simulated settings with tasks that represent real work.
Building on previous research showing that different types of noise can be detrimental for cognitive functioning and hospital patient outcomes, one study investigated the impact of shorter, 30-minute exposures of quiet versus prerecorded emergency room sounds on physicians’ performance on a set of medical questions.61 There was not a significant difference in task performance, yet physicians found the noisier conditions more distressing.61 However, other studies have shown that people can be subjectively unaware of how different noise conditions can affect them both behaviorally and physiologically. In one study, participants were exposed to different conditions of noise, simulating open office noise and a quieter environment, for bouts of 3 hours.62 Although participants did not perceive differences in stress, those in the noisy condition exhibited elevated urinary epinephrine levels (but not norepinephrine or cortisol), showed lower motivation in attempting to solve a puzzle, and even made fewer ergonomic adjustments to their workstations compared to those in the quiet condition.62 Interestingly, other research has found that the type of noise to which people are exposed, particularly low-frequency noise, matters a great deal.
In a lab setting, when participants were exposed to low-frequency noise, they exhibited poorer performance on proofreading and grammatical reasoning tasks and felt more annoyed than when they were exposed to a mixed noise condition of the same intensity.63 The effects were more pronounced for those who rated themselves as highly sensitive to noise, and the normal circadian cortisol decline during the session was also impaired.63 Low-frequency noise can have other detrimental effects as well—in fact, very low frequency noise has been found to cause aural pain in many studies.64 Taken together, these findings indicate that noise, especially low-frequency noise, consistently stimulates the physiological stress response whether or not those who are exposed are subjectively aware of it.
In real-world research settings, even though the effects of single variables on performance, behavior, and physiological and psychological outcomes are difficult to disentangle, they are important to review. In open-office settings there are several contributing factors besides noise (e.g., light, architectural features, social dynamics, air quality, thermal comfort) that may affect observed differences. In one study, workers in an open plan setting were more likely to perceive noise and thermal discomfort, central nervous system symptoms, and mucous membrane irritation compared to workers in more cellular (i.e., enclosed) office settings.65 In another study, workers in open plan settings also reported more displeasure with noise levels compared to those in more private settings, yet those in the more private offices did not experience the beneficial social aspects those in the open plan enjoyed.66 Lack of control, personalization, type of work, and perceived privacy are all other important factors in determining the appropriateness of workspace design.
One recent workplace development is the “flex” office, where employees spend a significant portion of their time teleworking, and have no assigned workspaces when they are in the office. Studies of this type of design have reported a lack of control and personalization, but better ratings compared to strict open plan offices on several dimensions including social interaction and privacy.66 In another study, a switch from private to open plan offices was particularly detrimental for people whose work was less collaborative, as participants felt decreases in privacy, concentration, and performance, and increases in distraction and coping behavior.67 Interestingly, the noise levels were similar in this study, but the patterns were different; the private offices had noise patterns with more variability over time compared to the open plan office space.66
Individual differences clearly matter when determining a design strategy for workspaces. We have seen how individual differences in noise sensitivity can affect reported impacts of environments on health outcome variables. Other research is beginning to uncover interactions between variables like personality, age, and workspace design characteristics. This is important because it may help us understand why significant proportions of building occupants are often not satisfied even when all design standards are met.68 One study showed the importance of measuring personality variables in the context of work space design. Compared to those low on neuroticism, workers high on neuroticism experienced less perceived control over workspaces that were rated as more exposed, while no differences were found between workspaces rated as more enclosed.69
Importantly, other interactions, like those between environmental variables typically measured in isolation, may also be important. Advances in wearable sensing technology for environmental and physiological variables make this possible when combined with, and not merely replacing, more common methodologies for collecting subjective measures.
The health benefits of exercise and regular physical activity have been well documented and have consistently been emphasized in policy interventions at many levels of government. Because the environment plays a dynamic role in the decisions individuals make regarding physical activity, a recent concentration of emphasis on built environment interventions has gained momentum. If fact, the US surgeon general and Department of Health and Human Services recently initiated Step it Up!—a call to action for promoting walking and walkable communities.70
Community-scaled design interventions can have lasting public health benefits when the factors of the built environment leading to increased physical activity are better understood. It is well established that higher levels of street connectivity, residential density, and mixed-use land usage (i.e., developments that have a mix of residential and commercial spaces) are associated with higher physical activity.71 Also, neighborhoods that are low in mixed use and are characterized by curvilinear suburban development are also associated with less walkability.72 Physical activity is also affected by the availability of the natural environment and view of nature. However, more research is needed to better understand the individual motivating mechanisms that play roles in people’s choices to interact with nature. For instance, policies that highlight how the natural environment can motivate physical activity routines may be beneficial.73
A current challenge is to develop valid and reliable measures to study the effectiveness of design interventions on physical activity and health. Because there are many types of outcome measurements employed including traditional surveys, geographic information system data, and direct observational measures, there is a large amount of variability in how specific programs aimed at promoting physical activity are evaluated.74 Policy intervention grading systems with the highest tiers reserved for evaluations that rely on significant positive health outcomes in peer-reviewed studies might be part of the solution going forward.75
Characteristics of the built environment that affect physical activity in vulnerable populations, such as children and older adults, are particularly important to understand. Several studies have shown that children’s activity levels are linked to publicly provided recreational facilities, sidewalk availability, access to public transportation, and controlled intersections.76 Interestingly, perceived neighborhood safety appears to be an important predictor for adult activity72 but less of a clear link for children.75 For a community to truly be walkable for older adults, specific barriers need to be addressed. Environmental hazards like traffic and fall risks are examples of these barriers and are closely tied to older adults’ walking choices.77
At the building scale, characteristics of the built environment may play a critical role in physical activity choices that people make on a daily basis. It is known that office workers tend to be more sedentary during certain hours of the workday and at night,78 but we do not fully understand the features of space that can interact with social dynamics and types of work to encourage nonsedentary behavior and shorter sitting bouts. Two such successful interventions are the adoption of point-of-decision prompts and prominent staircases.
Point-of-decision prompts are those that prompt the occupant to consider a choice they have, such as taking the stairs or the elevator, using signage or other strategies. Several studies of this type of intervention have shown evidence of increased physical activity, but experts caution that the local context is important to understand.79 For instance, when one office building’s staircase was decorated with interactive paintings, maps, and storyboards that the occupants could contribute to, staircase use dramatically increased,80 but such a tailored intervention may have a different impact depending on each office’s culture. Additionally, many forward-thinking companies, organizations, and schools have implemented dynamic, flexible design solutions like standing desks for both individual and team work.
Optimizing safety features in an environment can positively impact physical and psychological aspects of health and well-being. Accessibility, or how well a room, building, or neighborhood can support the needs of people across cognitive, sensory, physical, and psychological domains, provides a means to gauge the safety, whether real or perceived, of an environment. Increased accessibility benefits not only persons with disabilities but also people across the lifespan with different developmental capabilities and skillsets. Ideally, the demands of the environment should be consistent with the capabilities of the individual using it. For example, lifespan housing designed for aging in place recommends including design features such as zero step entrances and kitchen cabinetry that allows someone to work in a seated position.81 These practices are increasingly becoming the standard in communities for those 55 years and older. While some aspects of public space design supporting physical accessibility are federally regulated through the American with Disabilities Act standards,82 most other accessibility dimensions such as cognitive and sensory accessibility are less directed. Emerging research on interactions between the environment and sensation, perception, and cognition should be used to update regulations and improve accessibility.
When an environment is perceived to be unsafe, it is psychologically inaccessible. Both real and perceived safety impact health behaviors including the extent to which people walk to school, play outdoors, and connect with their community. A review on crime, health, and environment concluded that while there are well-established direct links between crime and victim health, effects of crime and fear of crime on the well-being of surrounding populations are less clear and may be better assessed by measures of social cohesion.83 However, reviewers found that the most promising interventions to lessen fear of crime are small-scale interventions that reduce neglect, including reducing litter and vandalization (graffiti), in public areas such as transportation hubs.82
Additional threats to personal physical safety and mobility at the neighborhood level often occur along pedestrian and bike routes with improper separation of vehicular traffic or unsafe intersection crossings, poorly maintained paths due to weather or disrepair, and the absence of signage that enhances navigation through complex environments.84 In 2007, the World Health Organization published a guide to global age-friendly cities, identifying key environmental barriers to active aging across the life cycle.85 While this guide can benefit designers to improve the quality of the environment and related safety issues, it is also relevant for clinicians to raise awareness of the types of environmental hazards facing aging populations.
Improving accessibility for persons with sensory differences including low vision, deafness, age-related sensory decline, and sensory-processing disorders increases safety and reduces incidence of injury while promoting increased independence, aging in place, and community engagement. Creative design strategies can be used to prevent falls, such as including elements to boost contrasts in elevation changes, and removing head and body obstacles along paths that can cause injury. Other design interventions can be used to improve wayfinding, such as incorporating salient navigation cues with redundancy across the senses. In combination, such design features can create more accessible environments for all populations. In environments and communities where these strategies are lacking, assistive technology devices are increasingly being used to boost awareness of environmental cues and reduce anxiety for managing complex and novel environments.
Much of the EBD research was originally driven by the goal to improve safety and reduce injury to both patients and staff in healthcare settings. Healthcare administrators are increasingly relying on environmental interventions to reduce medical errors. Examples of such design strategies include improving acoustics and eliminating environmental distractions, reducing healthcare-associated infections (HAIs) by eliminating surface air and water points of infection transmission, reducing patient falls by employing nonslip surfaces, and changing unit configurations to improve clinical staff visibility and monitoring of the patient.86 Healthcare workers can also benefit from EBD practices: reconfiguring the organization of patient rooms has been able to reduce the amount of walking for nursing staff and increase their visibility of patients, and ceiling lifts in patient rooms have decreased staff injuries from lifting patients. All of these interventions have not only health-related benefits but also economic benefits for the consumer and for the healthcare and insurance industries. Clinicians can participate in the design process through role-playing exercises with designers in mocked-up, stage-like settings to improve communication of their practices and needs, including differences in cultural demographics of patients, to optimize the design of the physical environment before it is completed.
Social connectedness is an important factor to consider when evaluating a design at the building or community scale, because it can affect how people’s relationships develop with neighbors and levels of social support, both key ingredients to sustaining or improving mental health and even buffering against infectious diseases. At the neighborhood scale, social connectedness can be influenced by densities of both traffic and people. In one study, researchers found that residents on busier streets had lower numbers of both friends and acquaintances on those streets compared with residents on less busy streets.87 In fact, several studies have shown better social connectedness for residents in low-rise or detached homes compared with residents in high-rise buildings.88 Safety also seems to be connected to social connectedness. In one study of older adults with chronic health problems, higher neighborhood safety predicted higher levels of social cohesion, which in turn predicted participation in everyday activities.89 Neighborhood walkability may contribute to social connectedness, as it can facilitate participation in activities with other neighbors. At a smaller scale, from the way entrances to residences are set up to the way furniture is arranged within a shared space, the built environment can also influence social connectedness.
Social interactions have been found to be highest in residential units when their entrances are closer rather than farther away, when they are across from one another, and when they connected to major foot traffic paths or gathering areas.88 However, at certain densities, crowding can become a problem. Increased numbers of families living in multifamily dwellings tend to have poorer parent–child relationships and exhibit more social withdrawal.88 Moreover, perceived crowding can happen more easily on long corridors versus short corridors. In one classic study that included an experimental manipulation, dorm residents in long corridors were more likely to experience crowding, had more difficulty in regulating social contact with neighbors, and exhibited higher levels of learned helplessness compared with residents living in dorms with shorter corridors.90 Inside shared spaces, social interactions can also be influenced by the arrangement of furniture and types of workspaces.
By creating focal points of interaction, placing furniture at socially close distances around tables has been shown to lead to increased social interactions in psychiatric patient populations and in the workplace.88 In the workplace, lines of sight and visual paths can be beneficial for collaboration and social connectedness, but there are important work-related tradeoffs that have to be considered, such as noise pollution.91 It is important to consider the type of work being done and the existing culture of a workforce before implementing changes from cellular offices to open plan offices, as there are conflicting effects of social benefits and coworker relations in different populations.66,67,92
Both the outdoor and indoor environment play important roles in affecting human health, well-being, and performance. Many of these effects can be taken advantage of in daily life by informed individuals or through recommendations from their physicians. Poor outdoor air quality can lead to disproportional negative health outcomes for children, the elderly, and populations proximate to pollution sources or environmental hazards. Indoor air quality can similarly affect human health, as limited ventilation and chemical off-gassing from building and furniture materials can be detrimental to both health and cognitive performance. Luckily, the natural environment can offer a reprieve from the myriad elements of fatigue and sedentary behavior often found in the indoor environment. Through strategies of either incorporating natural elements within the indoor environment or promoting interaction with nature in parks or similar settings, people of all populations can benefit, both physiologically and psychologically. One element of the natural environment, daylight, can also promote healthy circadian rhythms through the use of windows and other artificial means. Light can also be filtered for different wavelengths later at night. Chronic noise, particularly low-frequency noise, can be detrimental for cognitive performance in many populations, but less is known about the interactions between different sensory elements of the environment, particularly in real-world settings. At the neighborhood level, walkability and mixed-use land planning are paramount. Physical activity can be encouraged by the removal of hazards and the visibility of neighborhood characteristics like markets and parks. Walkable areas are only truly accessible where safety is not a concern, and they can lead to increases in social connectedness, a protective factor for both mental and physical health.
Much of the current literature on the environment’s effects on health and well-being is grounded in decades of work in fields with a varied disciplines and histories. Presently, many of these fields are coming together and being further informed by research methods only recently made possible by new technology. Such quantitative data-gathering methods are not meant to displace but rather to complement methods used previously. It is through this kind of scientific relationship that we can begin to truly understand how the environment we as a species have created and manipulated for ourselves can be now tailored to improve life. Given this depth of evidence for the impact of the built and natural environment on physical health and emotional well-being, it is important for integrative medicine practitioners to include information about optimizing environments in their armamentarium of integrative and preventive care.
1. World Health Organization. Preamble to the Constitution of the World Health Organization as Adopted by the International Health Conference. Vol 100. New York: Author; 1946.Find this resource:
2. US Department of Health and Human Services. The Secretary’s Advisory Committee on National Health Promotion and Disease Prevention Objectives for 2020. Phase I Report: Recommendations for the Framework and Format of Healthy People 2020. 2008. https://www.healthypeople.gov/sites/default/files/PhaseI_0.pdfFind this resource:
3. US Department of Health and Human Services. Healthy People 2020: An Opportunity to Address Societal Determinants of Health in the United States. 2010. https://www.healthypeople.gov/sites/default/files/SocietalDeterminantsHealth.pdfFind this resource:
4. Bernstein HM. The drive toward healthier buildings: the market drivers and impact of building design and construction on occupant health, well-being and productivity. McGraw Hill Construction—Smart Market Report. 2014:100. Bedford, MA.Find this resource:
5. Lewin K. Field theory and experiment in social psychology: concepts and methods. Am J Sociol 1939;44(6):868–896.Find this resource:
6. Hebb DO. The effects of early experience on problem solving at maturity. Am Psychol 1947;2:306–307.Find this resource:
7. Van Praag H, Kempermann G, Gage FH. Neural consequences of environmental enrichment. Nat Rev Neurosci 2000;1(3):191–198.Find this resource:
9. Snow J. The cholera near Golden-Square, and at Deptford. Medical Times and Gazette 1854;9:321–322.Find this resource:
10. Sternberg EM.Healing Spaces: The Science of Place and Well-Being. Cambridge, MA: Belknap Press of Harvard University Press; 2009.Find this resource:
11. King B. Environment and health. International Encyclopedia of the Social and Behavioral Sciences. Amsterdam: Elsevier; 2015:815–819.Find this resource:
12. Gruchalla RS, Pongracic J, Plaut M, et al. Inner City Asthma Study: relationships among sensitivity, allergen exposure, and asthma morbidity. J Allergy Clin Immunol 2005;115(3):478–485.Find this resource:
13. Suk WA, Murray K, Avakian MD. Environmental hazards to children’s health in the modern world. Mutat Res Rev Mutat Res 2003;544(2-3):235–242.Find this resource:
14. United States Environmental Protection Agency. Report to Congress on Indoor Air Quality. Volume II: Assessment and Control of Indoor Air Pollution. Washington, DC: 1989;244.Find this resource:
15. Mitchell CS, Zhang JJ, Sigsgaard T, et al. Current state of the science: health effects and indoor environmental quality. Environ Health Perspect 2007;115(6):958–964.Find this resource:
16. Ilyas S, Emery A, Heerwagen J, Heerwagen D. Occupant perceptions of an indoor thermal environment in a naturally ventilated building. ASHRAE Trans 2012;118:114–121.Find this resource:
17. Allen JG, MacNaughton P, Laurent JG, Flanigan SS, Eitland ES, Spengler JD. Green buildings and health. Curr Environ Health Rep 2015;2(3):250–258.Find this resource:
18. Allen JG, MacNaughton P, Satish U, Santanam S, Vallarino J, Spengler JD. Associations of cognitive function scores with carbon dioxide, ventilation, and volatile organic compound exposures in office workers: a controlled exposure study of green and conventional office environments. Environ Health Perspect 2015:1–32.Find this resource:
19. Coley DA, Greeves R, Saxby BK. The effect of low ventilation rates on the cognitive function of a primary school class. Int J Vent 2004;6(2):107–112.Find this resource:
20. Milton DK, Glencross PM, Walters MD. Risk of sick leave associated with outdoor air supply rate, humidification, and occupant complaints. Indoor Air 2000;10(4):212–221.Find this resource:
21. Melikov AK, Skwarczynski MA, Kaczmarczyk J, Zabecky J. Use of personalized ventilation for improving health, comfort, and performance at high room temperature and humidity. Indoor Air 2013;23(3):250–263.Find this resource:
22. Kuo M. How might contact with nature promote human health? Promising mechanisms and a possible central pathway. Front Psychol 2015;6:1093.Find this resource:
23. Chawla L. Benefits of nature contact for children. J Plan Lit 2015;30(4):433–452.Find this resource:
24. Ulrich R. View through a window may influence recovery from surgery. Science 1984;224(4647):420–421.Find this resource:
25. Taylor AF, Kuo FE, Sullivan WC. Views of nature and self-discipline: evidence from inner city children. J Environ Psychol 2002;22(1-2):49–63.Find this resource:
26. Wilson EO.Biophilia. Cambridge, MA: Harvard University Press; 1984.Find this resource:
27. Kellert SR, Heerwagen J, Mador M.Biophilic Design: The Theory, Science and Practice of Bringing Buildings to Life. Hoboken, NJ: Wiley; 2008.Find this resource:
28. Heerwagen J.Biophilia, health, and well-being. Restorative Commons: Creating Health and Well-Being Through Urban Landscapes. US Department of Agriculture, Forest Service, Northern Research Station; Newtown Square, PA; 2009:38–57.Find this resource:
29. Kardan O, Gozdyra P, Misic B, et al. Neighborhood greenspace and health in a large urban center. Sci Rep 2015;5:11610.Find this resource:
30. Kaplan S. The restorative benefits of nature: toward an integrative framework. J Environ Psychol 1995;15(3):169–182.Find this resource:
31. Berman MG, Jonides J, Kaplan S. The cognitive benefits of interacting with nature. Psychol Science 2008;19(12):1207–1212.Find this resource:
32. Gamble KR, Howard JH Jr, Howard DV. Not just scenery: viewing nature pictures improves executive attention in older adults. Exp Aging Res 2014;40(5):513–530.Find this resource:
33. Faber Taylor A, Kuo FE. Children with attention deficits concentrate better after walk in the park. J Atten Disord 2009;12(5):402–409.Find this resource:
34. Bratman GN, Hamilton JP, Hahn KS, Daily GC, Gross JJ. Nature experience reduces rumination and subgenual prefrontal cortex activation. Proc Natl Acad Sci U S A 2015;112(28):8567–8572.Find this resource:
35. Jansson M, Fors H, Lindgren T, Wiström B. Perceived personal safety in relation to urban woodland vegetation—a review. Urban & Urban Gree 2013;12(2):127–133.Find this resource:
36. Louv R.Last Child in the Woods: Saving Our Kids from Nature Deficit Disorder. Chapel Hill, NC: Algonquin Books of Chapel Hill; 2005.Find this resource:
37. Fjørtoft I. Landscape as playscape: the effects of natural environments on children’s play and motor development. Child Youth Environ 2004;14(2):21–44.Find this resource:
38. Li Q, Otsuka T, Kobayashi M, et al. Acute effects of walking in forest environments on cardiovascular and metabolic parameters. Eur J Appl Physiol 2011;111(11):2845–2853.Find this resource:
39. Ohtsuka Y, Yabunaka N, Takayama S. Shinrin-yoku (forest-air bathing and walking) effectively decreases blood glucose levels in diabetic patients. Int J Biometeorol 1998;41(3):125–127.Find this resource:
40. Park BJ, Tsunetsugu Y, Kasetani T, Kagawa T, Miyazaki Y. The physiological effects of Shinrin-yoku (taking in the forest atmosphere or forest bathing): evidence from field experiments in 24 forests across Japan. Environ Health Prev Med 2014;15(1):18–26.Find this resource:
41. Ward Thompson C, Roe J, Aspinall P, Mitchell R, Clow A, Miller D. More green space is linked to less stress in deprived communities: evidence from salivary cortisol patterns. Landscape Urban Plan 2012;105(3):221–229.Find this resource:
42. Detweiler MB, Sharma T, Detweiler JG, et al. What is the evidence to support the use of therapeutic gardens for the elderly? Psychiatry Investig 2012;9(2):100–110.Find this resource:
43. Diette GB, Lechtzin N, Haponik E, Devrotes A, Rubin HR. Distraction therapy with nature sights and sounds reduces pain during flexible bronchoscopy. Chest 2003;123(3):941–948.Find this resource:
44. Park S-H.Randomized Clinical Trials Evaluating Therapeutic Influences of Ornamental Indoor Plants in Hospital Rooms on Health Outcomes of Patients Recovering from Surgery. Manhattan, KS: Kansas State University; 2006.Find this resource:
45. Bowler DE, Buyung-Ali LM, Knight TM, Pullin AS. A systematic review of evidence for the added benefits to health of exposure to natural environments. BMC Public Health 2010;10:456.Find this resource:
46. Benedetti F, Colombo C, Barbini B, Campori E, Smeraldi E. Morning sunlight reduces length of hospitalization in bipolar depression. J Affect Disord 2001;62(3):221–223.Find this resource:
47. Walch JM, Rabin BS, Day R, Williams JN, Choi K, Kang JD. The effect of sunlight on postoperative analgesic medication use: a prospective study of patients undergoing spinal surgery. Psychosom Med 2005;67(1):156–163.Find this resource:
48. Beauchemin KM, Hays P. Dying in the myocardial in the dark: sunshine, gender and outcomes in infarction. J R Soc Med 1998;91(7):352–354.Find this resource:
49. Freedman DM, Dosemeci M, McGlynn K. Sunlight and mortality from breast, ovarian, colon, prostate, and non-melanoma skin cancer: a composite death certificate based case-control study. Occup Environ Med 2002;59(4):257–262.Find this resource:
50. Youngstedt SD, Kripke DF. Does bright light have an anxiolytic effect?—An open trial. BMC Psychiatry 2007;7:62.Find this resource:
51. Partonen T, Lönnqvist J. Bright light improves vitality and alleviates distress in healthy people. J Affect Disord 2000;57(1):55–61.Find this resource:
52. Stevens RG, Brainard GC, Blask DE, Lockley SW, Motta ME. Breast cancer and circadian disruption from electric lighting in the modern world. CA Cancer J Clin 2014;64(3):207–218.Find this resource:
53. Appleman K, Figueiro MG, Rea MS. Controlling light-dark exposure patterns rather than sleep schedules determines circadian phase. Sleep Med 2013;14(5):456–461.Find this resource:
54. Figueiro MG, Plitnick BA, Lok A, et al. Tailored lighting intervention improves measures of sleep, depression, and agitation in persons with Alzheimer’s disease and related dementia living in long-term care facilities. Clin Interv Aging 2014;9:1527–1537.Find this resource:
55. Figueiro M, Overington D. Self-luminous devices and melatonin suppression in adolescents. Light Res Technol 2015;0:10.Find this resource:
56. Shin JY, Yun GY, Kim JT. View types and luminance effects on discomfort glare assessment from windows. Energ Buildings 2012;46:139–145.Find this resource:
57. Hwang T, Kim JT. Effects of indoor lighting on occupants’ visual comfort and eye health in a green building. Indoor Built Environ 2010;20(1):75–90.Find this resource:
58. Leather P, Pyrgas M, Beale D, Lawrence C. Windows in the workplace: sunlight, view, and occupational stress. Environ Behav 1998;30(6):739–762.Find this resource:
59. Thayer JF, Verkuil B, Brosschot JF, et al. Effects of the physical work environment on physiological measures of stress. Eur J Cardiovasc Prev Rehabil 2010;17(4):431–439.Find this resource:
60. Park JY, Min BK, Jung YC, Pak H, Jeong YH, Kim E. Illumination influences working memory: an EEG study. Neuroscience 2013;247:386–394.Find this resource:
61. Folscher LL, Goldstein LN, Wells M, Rees D. Emergency department noise: mental activation or mental stress? Emerg Med J 2014;32(6):468–473.Find this resource:
62. Evans GW, Johnson D. Stress and open-office noise. J Appl Psychol 2000;85(5): 779–783.Find this resource:
63. Waye KP, Bengtsson J, Rylander R, Hucklebridge F, Evans P, Clow A. Low frequency noise enhances cortisol among noise sensitive subjects during work performance. Life Sci 2002;70(7):745–758.Find this resource:
64. Schust M. Effects of low frequency noise up to 100 Hz. Noise Health 2004;6(23):73–85.Find this resource:
65. Pejtersen J, Allermann L, Kristensen TS, Poulsen OM. Indoor climate, psychosocial work environment and symptoms in open-plan offices. Indoor Air 2006;16(5):392–401.Find this resource:
66. Danielsson CB, Bodin L, Difference in satisfaction with office environment among employees in different office types. J Archit Plann Res 2009;26(3):241–257.Find this resource:
67. Kaarlela-Tuomaala A, Helenius R, Keskinen E, Hongisto V. Effects of acoustic environment on work in private office rooms and open-plan offices—longitudinal study during relocation. Ergonomics 2009;52(11):1423–1444.Find this resource:
68. Freihoefer K, Guerin D, Martin C, Kim HY, Brigham JK. Occupants’ satisfaction with, and physical readings of, thermal, acoustic, and lighting conditions of sustainable office workspaces. Indoor Built Environ 2013;24(4):457–472.Find this resource:
69. Lindberg CM, Tran DT, Banasiak MA. Individual differences in the office: personality factors and workspace enclosure. J Archit Plann Res 2016;33(2):105–120.Find this resource:
70. US Department of Health and Human Services. Step It Up! The Surgeon General’s Call to Action to Promote Walking and Walkable Communities. l; 2015:18. Washington, DC.Find this resource:
71. Frank LD, Schmid TL, Sallis JF, Chapman J, Saelens BE. Linking objectively measured physical activity with objectively measured urban form: findings from SMARTRAQ. Am J Prev Med 2005;28(2):117–125.Find this resource:
72. Foster S, Giles-Corti B, Knuiman M. Neighbourhood design and fear of crime: a social-ecological examination of the correlates of residents’ fear in new suburban housing developments. Health Place 2010;16(6):1156–1165.Find this resource:
73. Calogiuri G, Chroni S. The impact of the natural environment on the promotion of active living: an integrative systematic review. BMC Public Health 2014;14(1):873.Find this resource:
74. Brownson RC, Hoehner CM, Day K, Forsyth A, Sallis JF. Measuring the built environment for physical activity: state of the science. Am J Prev Med 2009;36(4 Suppl):S99–S123 e112.Find this resource:
75. Brennan L, Castro S, Brownson RC, Claus J, Orleans CT. Accelerating evidence reviews and broadening evidence standards to identify effective, promising, and emerging policy and environmental strategies for prevention of childhood obesity. Annu Rev Public Health 2011;32:199–223.Find this resource:
76. Davison KK, Lawson CT. Do attributes in the physical environment influence children’s physical activity? A review of the literature. Int J Behav Nutr Phys Act 2006;3(1):19.Find this resource:
77. Lockett D, Willis A, Edwards N. Through seniors’ eyes: an exploratory qualitative study to identify environmental barriers to and facilitators of walking. Can J Nurs Res 2005;37(3):48–65.Find this resource:
78. Smith L, Hamer M, Ucci M, et al. Weekday and weekend patterns of objectively measured sitting, standing, and stepping in a sample of office-based workers: the active buildings study. BMC Public Health 2014;15:9.Find this resource:
79. Brownson RC, Haire-Joshu D, Luke DA. Shaping the context of health: a review of environmental and policy approaches in the prevention of chronic diseases. Annu Rev Public Health 2006;27:341–370.Find this resource:
80. Swenson T, Siegel M. Increasing stair use in an office worksite through an interactive environmental intervention. Am J Health Promot 2013;27(5):323–329.Find this resource:
81. Steinfeld E, White J. Levels of access. Inclusive Housing 2010:23–36.Find this resource:
82. Department of Justice. 2010 ADA Standards for Accessible Design. 2010:275.Find this resource:
83. Lorenc T, Petticrew M, Whitehead M, et al. Crime, fear of crime and mental health: synthesis of theory and systematic reviews of interventions and qualitative evidence. Natl I Health Res 2014;2(3).Find this resource:
84. O’Donnell E, Athey L, Skolnick G.Sidewalks and Shared-Use Paths: Improving Mobility and Designing Transit-Ready Communities. Institute for Public Administration, College of Human Services, Education and Public Policy, Newark, DE: University of Deleware; 2008. http://udspace.udel.edu/bitstream/handle/19716/3933/SidewalksSharedUsePaths2.pdf?sequence=1&isAllowed=yFind this resource:
85. World Health Organization. GlobalAge-Friendly Cities: A Guide. Geneva, Switzerland: WHO Press; 2007:76.Find this resource:
86. Sadler, B, Berry L, Guenther R, Hamilton D, Hessler F, Merritt C, Parker D. Fable Hospital 2.0: The Business Case for Building Better Health Care Facilities. In the report: The Hastings Center Report, Garrison, NY; 2001;41(1):13–23.Find this resource:
87. Appleyard D, Lintell M. The environmental quality of city streets: the residents’ viewpoint. J Am Inst Plann 1972;38(2):84–101.Find this resource:
88. Evans GW. The built environment and mental health. J Urban Health 2003;80(4):536–555.Find this resource:
89. Hand C, Law M, Hanna S, Elliott S, McColl MA. Neighbourhood influences on participation in activities among older adults with chronic health conditions. Health Place 2012;18(4):869–876.Find this resource:
90. Baum A, Aiello JR, Calesnick LE. Crowding and personal control: social density and the development of learned helplessness. J Pers Soc Psychol 1978;36(9):1000–1011.Find this resource:
91. Heerwagen JH, Kampschroer K, Powell KM, Loftness V. Collaborative knowledge work environments. Build Res Inf 2004;32(6):510–528.Find this resource:
92. Brennan A, Chugh JS, Kline T. Traditional versus open office design: a longitudinal field study. Environ Behav 2002;34(3):279–299.Find this resource: