The impact of gardening on nutrition and physical health outcomes: a systematic review and meta-analysis.

Community gardening has been widely recognized as a multicomponent approach that has affected a broad range of health and well-being outcomes. The objective of this study was to investigate the association between community gardening and nutrition and physical health among adults. A systematic review and meta-analysis were conducted. Five electronic databases were searched systematically. Quality of included studies was appraised by several quality assessment tools related to the study design of each included article. Evidence from 19 articles was included (14 cross-sectional studies, 4 quasi-experimental studies and 1 case-control study). Although the majority of included studies appeared to have moderate quality, there existed weaknesses in the methods used, including low response rate and lack of confounder controls. Due to diversity in the measurement units, only body mass index (BMI) data could be pooled to perform meta-analysis. The results suggest that gardening had a significantly positive effect on BMI reduction. Subgroup analysis showed that quasi-experimental and case-control studies produced greater pooled effect size than those of cross-sectional design. Funnel plot and Egger's test showed no significant evidence of publication bias. As robust evidence for the effect of community gardening on BMI reduction was found, this intervention should be integrated in health promoting policy to improve population health.