Conceptualising a Community-Based Response to Loneliness: The Representational Anchoring of Nature-Based Social Prescription by Professionals in Marseille, Insights from the RECETAS Project.

Background: Urban loneliness is rising worldwide and is a recognised public-health threat. Nature-Based Social Prescriptions (NBSPs), guided group activities in natural settings, are being piloted in six cities through the EU project RECETAS. However, in new contexts such as Marseille, its implementation is constrained by professionals' limited knowledge of the concept.

Objectives: (i) Exploring how professionals in Marseille (France) conceptualise NBSPs; (ii) Identifying perceived facilitators and barriers to implementing NBSPs among residents facing social isolation and loneliness.

Methods: Twelve semi-structured interviews were conducted with health, social-care, and urban-environment professionals selected via network mapping and snowball sampling. Verbatim transcripts underwent inductive thematic analysis informed by Social Representation Theory, with double coding to enhance reliability.

Results: Five analytic themes emerged: (1) a holistic health paradigm linking nature, community, and well-being; (2) stark ecological inequities with limited green-space access in deprived districts; (3) work challenges due to the urgent needs of individuals facing significant socio-economic challenges in demanding contexts; (4) a key tension between a perceived top-down process and a preference for participatory approaches; (5) drivers and obstacles: strong professional endorsement of NBSPs meets significant systemic and institutional constraints.

Conclusions: Professionals endorse NBSPs as a promising approach against loneliness, provided programmes tackle structural inequities and adopt participatory governance. Results inform the Marseille RECETAS pilot and contribute to global discussions on environmentally anchored health promotion.