The health benefits of the great outdoors: A systematic review and meta-analysis of greenspace exposure and health outcomes.

•Greenspace exposure is associated with wide ranging health benefits across 143 included studies.•Meta-analysis showed statistically significant reductions in diastolic blood pressure, salivary cortisol and heart rate.•Meta-analysis found statistically significant decreases in incidence of diabetes, all-cause and cardiovascular mortality.•A number of meta-analyses were limited by poor study quality and high levels of heterogeneity.•Greenspace and street greenery may form part of a multi-faceted approach to improve a wide range of health outcomes.