Introduction: Despite growing evidence for the multiple health benefits of community gardening, longitudinal studies based on quantitative data are needed. JArDinS is a quasi-experimental study aimed at assessing the impact of community garden participation in the adoption of more sustainable lifestyles. Materials and Methods: Gardeners starting gardening in a community garden in Montpellier (France) were recruited in 2018. Volunteers with no experience in community gardening and matched for age range, gender, household income and household composition were recruited in a control group. A recruitment goal of 80 participants per group was determined to detect a 30% increase in F&V supply in the gardeners group. Participant were issued with three tools: a Food Supply Dairy to collect data on monthly household’s food supply, a triaxial accelerometer to measure physical activity and an online questionnaire on mental and social health, sensitivity to food waste, and connection with nature. Measures have been collected at baseline and will be repeated 12 months later. Data collected are examined conjointly to assess the sustainability of lifestyles in its social/health, environmental and economic dimensions. Change of outcomes after 1 year will be compared between the natural experiment and the control groups, to evaluate the effect of access to a community garden on the sustainability of lifestyles. Results: A final number of 77 participants per group were enrolled at baseline, which is 4% less the original recruitment goal. Baseline data for the natural experiment group and the control group are currently being analysed and will be presented. Discussion: This study will provide valuable information about the potential of community gardens to favor sustainable lifestyles, based on a robust quasi-experimental design allowing causality evaluation. Findings could help developing policies toward more sustainable urban planning favoring both human and environmental health.