Background
Obesity is a major, modifiable risk factor for at least 13 types of cancer worldwide and remains a key public health challenge across Europe and globally. Environmental interventions promoting healthy food practices have been widely implemented as population-level strategies to prevent obesity by shaping physical, economic, social, and policy food environments. In recent years, a growing number of systematic reviews have examined these environmental interventions across diverse contexts. This fragmentation of the evidence across intervention types, populations and outcomes limits their usability for public health decision making and cancer prevention policy in Europe.

Objectives
As part of the Cancer Prevention Europe Intervention Evidence Portal, this umbrella review aims to map and categorise evidence from existing systematic reviews on environmental interventions promoting healthy food practices for obesity prevention, using the ANGELO framework. This review seeks to: (1) characterise the populations targeted by environmental interventions; (2) classify intervention types across physical, economic, social, and policy food environments; (3) describe the dietary, behavioural, and obesity-related outcomes assessed in existing reviews, and, where available, cancer outcomes, and (4) identify evidence gaps and underrepresented domains relevant to population-level obesity and cancer prevention in Europe.

Methods
A descriptive umbrella review with a narrative evidence mapping approach will be conducted. Systematic reviews of environmental interventions promoting healthy food practices will be identified through searches in the Cochrane Library, Epistemonikos, MEDLINE, and Embase. Eligible reviews will include population level interventions targeting children, adolescents, or adults in real-world food environments. Interventions will be classified according to the ANGELO framework. Data will be extracted on populations, intervention characteristics, environmental domain, and reported outcomes related to dietary behaviours, overweight, obesity, and, where available, cancer. Overlap of primary studies across reviews will be assessed and reported in accordance with the Graphical Representation of Overlap for Overviews. Findings will be synthesised narratively and summarised in tables to support interpretation for public health practice and policy.

Results
The review is currently ongoing. Preliminary searches suggest substantial heterogeneity across environmental domains, intervention approaches, populations, and outcomes reported in existing reviews, supporting the need for a structured and policy-relevant mapping of existing synthesized evidence.

Conclusions/Implications
By mapping existing systematic reviews across food environments by domains and outcome types, this umbrella review will provide a coherent overview of the evidence and the gaps most relevant to obesity prevention in Europe. These findings will help guide future research priorities and highlight areas where further systematic reviews are neededto support public health research in obesity and cancer prevention in both Europe and in comparable global settings.