Green space exposure and colorectal cancer: A systematic review

Green space has been linked to colorectal cancer, but the evidence is still limited and inconclusive. This review aimed to investigate the relationship between green space and CRC. The studies were searched using three primary journal databases: PubMed, Scopus, and Web of Science. The retrieved citations were screened, and data from articles about GS exposure and CRC were extracted. The Newcastle-Ottawa Quality Assessment Form for Cohort Studies was used to evaluate the studies' quality. Five of the 1792 articles identified were eligible for the final review, which included five cohort studies published between 2017 and 2022. Each one article from the United States, the United Kingdom, France, Belgium, and Germany and All studies are of high quality. Four studies reported CRC incidence and one study reported CRC mortality from GS exposure. There was no significant association between GS attributes (Normalized Difference Vegetation Index (NDVI), surrounding greenness, surrounding green area, proximity to GS (agricultural lands, urban GSs, and forests), and count of recreational facilities and parks) with CRC. Only one study discovered that a healthier ecosystem was linked to a lower CRC risk. Although the evidence is still limited, the findings may indicate the presence of other factors in the relationship between GS and CRC. Future research should continue to focus on the variation of GS and the factors that influence it. Specific attention to the development of GS has the potential to produce benefits while mitigating cancer risk.