Introduction Objective and accurate dietary monitoring is critical for comprehensive dietary assessment and improving nutritional health outcomes. The rapid development of wearable sensing technology presents a promising solution for effective dietary monitoring that reduces recall bias and increases user convenience, contributing to clinical chronic disease management and nutritional research. This systematic review aims to explore the effectiveness and practicality of wearable sensors in monitoring dietary behaviours, while also examining the latest advancements in the field since 2020.

Methods and Analysis Adhering to PRISMA-P guidelines, we will conduct a comprehensive search across MEDLINE, EMBASE, PubMed, IEEExplore, and Web of Science for research published between January 2020 and January 2024 Studies that involved human participants using wearable sensors for monitoring dietary intake will be included. However, studies solely discussing the development of algorithms or applications for these sensors will be excluded. Our review outcomes focused on evaluating the design of the sensors, their performance metrics, and user experience.

Ethics and Dissemination Findings of this systematic review will be disseminated through peer-reviewed journals, conferences, and seminar presentations. The data used does not include individual patient data, so no ethical approval is required.

Systematic Review Registration Number PROSPERO Registration ID: CRD42024531570

Strengths and Limitations of This Study 1. This study will update the latest advancements in wearable sensing devices for monitoring food intake published from 2020 to date.

2. This study follows a PICOS framework to formulate research questions and inclusion/exclusion criteria.

3. This study uses a well-structured search strategy, using MeSH and equivalent terms to search across five medical and engineering databases to provide a precise, comprehensive, and multidisciplinary perspective on the topic.

4. The nature of the available data precludes the possibility of conducting a meta-analysis, limiting the ability to quantitatively synthesize study findings. However, the narrative data synthesis adheres to the Synthesis Without Meta-analysis (SWiM) guidelines, ensuring a structured approach to qualitatively integrating study outcomes.

5. The inclusion criteria were restricted to peer-reviewed journals published in English. This excludes potentially relevant conference papers and studies published in other languages, which may limit the comprehensiveness of the analysis.

The authors have declared no competing interest.

This work was supported by the Dame Julia Higgins Postdoc Collaborative Research Fund. The sponsor has no role in composing the study design, collection, management, analysis, and interpretation of data.

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Ethical approval is not required for this systematic review protocol.

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