A systematic review of evidence for the added benefits to health of exposure to natural environments
Natural environments may provide added health benefits above and beyond human-made environments
In recent years, a number of studies have examined the role of natural environments in human health, however little research has attempted to synthesize the findings. The purpose of this study by Bowler and colleagues was to conduct a systematic review of research to determine whether there is an added benefit from activities in natural environments that goes above and beyond those in more human-made environments.
Bowler and colleagues searched 19 electronic libraries and databases, used additional Web search engines, and also searched the Web sites of public health and environmental organizations for relevant studies. They used a variety of keywords to assist in their search, and checked the bibliographies of articles they ultimately included in their review for additional references of relevance and value. They specifically focused on studies where there was a comparison of the same activity in natural and human-made environments so that the effect of the environment could be determined. Their primary criterion for including studies in the review were those that involved collection of data on any measure of health and well-being after what they defined as direct exposure to a natural environment and after exposure to a synthetic environment. The authors examined 25 studies that included a variety of types of natural environments (e.g., public parks or university campuses) and outcome measures (e.g., emotions or attention/concentration).
In analyzing the study results, Bowler and colleagues found that activities in a natural environment resulted in reduced negative emotions (e.g., anger, fatigue and sadness) as compared to similar activities in a human-made environment. The authors also found that activity in a natural environment may result in improved attention as compared to a human-made environment, however, the added benefit disappeared when pretest differences were taken into account. Bowler and colleagues did not find strong evidence of differences in terms of other physiological variables examined, such as blood pressure, however, there were not many studies in this area to examine at the time this review was conducted.
This article provides a valuable contribution toward our understanding of the benefits of nature to human health. In concluding their article, the authors discuss characteristics of the studies they examined and suggest areas of future research.
Bowler, D. E., Buyung-Ali, L. M., Knight, T. M., Pullin, A. S., (2010). A systematic review of evidence for the added benefits to health of exposure to natural environments. BMC Public Health, 10(456)