Food system determinants of seasonal malnutrition in children under 5 years in sub-Saharan Africa: a scoping review protocol

Abstract

Introduction

Child malnutrition remains a pressing public health challenge in sub-Saharan Africa (SSA), where approximately 148 million children are stunted and 45 million are wasted. Although often conceptualised as a persistent condition, evidence indicates that malnutrition among children under 5 years frequently follows seasonal patterns shaped by agricultural cycles, climatic variability and socioeconomic conditions. Current interventions have paid limited attention to the food system dynamics that underpin these fluctuations. Adopting a system perspective, this scoping review will synthesise existing evidence on the food system determinants of seasonal malnutrition in children under 5 years in SSA.

Methods and analysis

The review will be conducted in accordance with the Joanna Briggs Institute methodological framework for scoping reviews and reported following Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Extension for Scoping Reviews (PRISMA-ScR) guidelines. A comprehensive search will be undertaken across electronic databases (Google Scholar, ProQuest Central, PubMed, Scopus and African Index Medicus) for literature published from 2015 onwards. Grey literature will also be sought from institutional repositories of the WHO, United Nations Children’s Fund, Food and Agriculture Organization and World Food Programme. Screening of titles, abstracts and full texts will be performed independently by two reviewers using predefined eligibility criteria. Data extraction will capture study characteristics and food system determinants of seasonal malnutrition at micro, meso and macro levels. The Food Insecurity and Vulnerability Information and Mapping Systems framework will guide the analysis and synthesis.

Ethics and dissemination

As this review involves analysis of previously published data, ethical approval is not required. Findings will be disseminated through a peer-reviewed publication and social media engagements. Results will inform the development of integrated system-based approaches to address seasonal malnutrition in children under five in SSA. The full study protocol, datasets and supplementary forms will be published in an open-access repository in compliance with the Findability, Accessibility, Interoperability and Reuse principles.

Registration

This scoping review protocol is registered with the Open Science Framework (https://doi.org/10.17605/OSF.IO/RU4ZX).

STRENGTHS AND LIMITATIONS OF THIS STUDY.

• Follows the Joanna Briggs Institute scoping review framework and Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Extension for Scoping Reviews (PRISMA-ScR) guidelines to ensure a structured and transparent approach to evidence synthesis.

• Employs Sysrev, an open-access web-based platform, for data management to ensure methodological rigour and transparency.

• Applies framework analysis to systematically analyse food system determinants at micro, meso and macro levels.

• Limits evidence to English-language publications, potentially omitting relevant non-English studies.

• It may be limited by variability in data quality across included studies, affecting the depth of synthesis.

Introduction

Malnutrition in children under 5 years remains a critical global public health challenge, with 45 million children wasted and 148 million stunted worldwide.¹ Sub-Saharan Africa (SSA) bears a disproportionate burden, accounting for two out of every five stunted children and more than one quarter of all wasted children globally.^{1 2} Regional disparities within SSA are stark, with Central Africa recording the highest stunting rates at 37.4%, well above continental (30%) and global (22.3%) averages.² While Southern and Eastern Africa show relatively lower wasting rates (<4% and 5%, respectively), Western and Northern Africa exceed both continental (5.8%) and global (6.8%) averages.^{2 3} Beyond these visible forms of undernutrition, micronutrient deficiencies represent an even more pervasive yet less recognised challenge, affecting nearly twice as many children as those with stunting and wasting combined in low- and middle-income countries.^{4 5}

Malnutrition has profound consequences for child health and development across the life course. Wasting and micronutrient deficiencies compromise immune function, increasing susceptibility to infections and elevating mortality risk in young children.^{5 6} Early stunting impairs cognitive development and predisposes children to poor educational outcomes, disability and increased risk of non-communicable diseases in adulthood.^{7 8} Addressing malnutrition is fundamental to achieving Sustainable Development Goals 2 and 3, which target the elimination of hunger and malnutrition and the reduction of preventable child deaths.⁹ However, SSA’s progress toward these 2030 targets remains constrained by persistent poverty, food insecurity and weak health systems.⁸

While malnutrition in children is often discussed as a persistent issue, evidence suggests that it often exhibits distinct seasonal patterns.^{10 11} The seasonality of malnutrition refers to the cyclical nature of food scarcity and abundance, which often corresponds to the agricultural calendar.^{1 12} This seasonal variation, driven by agricultural cycles, climatic conditions and socioeconomic factors, influences food security and disproportionately affects vulnerable populations like children under 5 years.^{6 10 13}

Studying the seasonality of malnutrition in children under five from a food system perspective offers a deeper understanding of the dynamics of seasonal nutrition outcomes. Food systems refer to the network of actors and their interconnected activities that span the entire food value chain, from production and processing to distribution, consumption and disposal.^{14 15} These systems involve food sourced from agriculture and fisheries, which are influenced by the broader economic, social and environmental contexts in which they exist. These systems are fundamental to ensuring food security through food availability, accessibility, utilisation and stability.⁷ While the global food system has responded to rapid population growth by increasing food production, in some regions of the world, particularly SSA, inadequate food production remains a major cause of food and nutrition insecurity.¹⁴ This production-centric approach potentially assumes universal access to food, but systemic inequities such as economic inequality, poor infrastructure and market imbalances result in uneven distribution, leaving many without access.¹⁶

Despite ongoing interventions to address malnutrition, many strategies focus on immediate food aid, supplementation or disease-focused interventions,^{1 11} rather than addressing the underlying food system factors that contribute to seasonal malnutrition. The evidence on the food system determinants of seasonal malnutrition in children under five is still emerging, heterogeneous and scattered across diverse disciplines (eg, nutrition, agriculture, climate, economics and health systems).^{15 16} Furthermore, while current literature has explored individual components of the food system,^{13 15} it often does so in isolation, without considering how these elements interact to drive the seasonality of malnutrition. This fragmented approach has resulted in a significant gap in the literature, which calls for the need to examine the breadth of evidence on the seasonality of malnutrition from a system perspective.

This scoping review aims to map the existing evidence on food system determinants of seasonal malnutrition in children under 5 years in SSA and identify research gaps to inform future systematic reviews and policy-relevant studies. It applies the Food Insecurity and Vulnerability Information and Mapping Systems (FIVIMS) framework,¹⁷ making the following contributions. First, the review will advance the scholarly understanding of the seasonality of malnutrition through a food system perspective, moving beyond the current literature to place a focus on the structural and systemic drivers that shape nutrition outcomes in children under five. With this new understanding, the review will stimulate the policy discourse in the direction of systems thinking rather than the current fragmented approach, helping to bridge the policy gap in addressing the seasonality of malnutrition. Finally, this review will contribute to the scholarly discourse by proposing new directions for future exploration of this topical issue.

Review questions

This review seeks to address the following question: what is known about the food system determinants of seasonal malnutrition in children under 5 years in SSA, and what are the key evidence gaps? To explore this, the review specifically seeks to answer the following questions:

1. What evidence exists on the micro, meso and macro-level food system determinants of seasonal malnutrition in children under five in SSA?

2. How has existing research described the ways food system dynamics influence the seasonality of child malnutrition?

3. What interventions within food systems have been reported, and where are the evidence gaps, in relation to mitigating seasonal malnutrition in children under five in SSA?

Inclusion criteria

The inclusion/exclusion criteria for the review are based on the population, concept and context framework defined in the JBI (Joanna Briggs Institute) manual for evidence synthesis.¹⁸ The inclusion/exclusion criteria are structured to capture studies that specifically examine the intersection between food systems and seasonal variations in child malnutrition within the SSA context.

Population

We will include studies focusing primarily on children under 5 years of age (0–59 months). Studies with mixed age groups will be included where children under five constitute at least 50% of participants or where separate data for this age group can be extracted. This ensures that findings remain representative of the under-five population while maximising evidence capture.¹⁸ We will also include studies examining caregivers or households where child nutritional outcomes for children under five are the primary focus. Studies will be excluded if they focus only on older age groups (school-age children, adolescents, adults or the elderly). Mixed-population studies will also be excluded where under fives make up less than 50% and data are not disaggregated. Maternal nutrition studies will be excluded unless they directly link to child under-five outcomes. These exclusion conditions will help to avoid dilution of findings and maintain focus on the target population.^{10 19}

Concept

The concept of interest is the seasonality of malnutrition in relation to food system determinants. Studies will be included if they assess seasonal malnutrition (wasting, stunting, underweight, micronutrient deficiencies) and link it to food system determinants such as production, processing, distribution, access, utilisation or stability. Studies that evaluate food system interventions or mechanisms influencing seasonal nutrition outcomes will also be considered. However, studies will be excluded if they assess malnutrition without seasonality, food systems without nutrition outcomes or focus only on non-food system factors (eg, genetics, infections and water, sanitation and hygiene).

Context

This review will focus on studies conducted in SSA countries as defined by the World Bank classification. Multicountry studies will be included if they include at least one SSA setting with extractable data. Studies may be conducted in rural, urban or peri-urban settings within SSA and include community-based, population-based or health facility-based studies with community relevance. Studies will be excluded if they are conducted exclusively outside SSA, focus solely on clinical or hospital settings in SSA without a community food system context, or where the geographic location cannot be determined.

Types of evidence sources

The review will include empirical quantitative (cross-sectional, cohort, case-control, randomised controlled trials, quasi-experimental), qualitative (ethnographic, phenomenological, grounded theory, case studies), mixed-methods studies and evidence syntheses (systematic reviews, scoping reviews, meta-analyses). Grey literature from the WHO, United Nations Children’s Fund (UNICEF), the Food and Agriculture Organisation (FAO) and the World Food Programme (WFP) will also be considered. Only English-language sources published from January 2015 to the present will be included. Eligible studies must be available in full text. Studies will be excluded if they are conference abstracts, study protocols or proposals without results. Where multiple versions or updates of the same study exist, only the most recent will be retained. We will also exclude studies that cannot be obtained in full text despite attempts through institutional access, interlibrary requests or direct contact with authors. Non-English publications and studies published before 2015 will not be included.

Methods

This review follows the JBI framework¹⁸ for conducting scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Extension for Scoping Reviews (PRISMA-ScR) reporting guidelines.¹⁹ Given the broad, heterogeneous and interdisciplinary nature of the evidence,¹¹ a scoping review is the most appropriate approach to map existing knowledge on food system determinants of seasonal malnutrition in children under five in SSA and to identify gaps to inform future research and policy.^{18 20 21} We plan to begin the review in September 2025 and complete it by February 2026 (see review timeline in online supplemental appendix 1). The details of the review are outlined in our registered protocol.²²

Search strategy

A preliminary search conducted in September 2024 on PROSPERO and the Open Science Framework database did not yield any ongoing reviews on the topic. The substantive search will be conducted in the following electronic databases: Google Scholar, Proquest Central, PubMed, Scopus and African Index Medicus. We will also search for grey literature in the institutional repositories of the WHO, UNICEF, FAO and WFP. A combination of keywords and controlled vocabulary terms (see online supplemental appendix 2) will be used to maximise the retrieval of relevant studies. Boolean operators (AND, OR) will be employed to connect keywords to allow for varied combinations. The full details of the search strings and strategies for each database are provided in online supplemental appendix 2. A manual search of the reference lists of included studies will be conducted to identify any additional relevant studies that may have been missed. The final search results and screening will be fully documented in the final report and presented using a PRISMA flow diagram.

Evidence screening and selection

Articles retrieved from online database searches will be imported into Sysrev, an open-access, web-based platform designed for collaborative and systematic evidence synthesis. The platform will automatically detect and remove duplicate records before the screening process begins. The screening process will be conducted in two stages. First, two reviewers will independently assess article titles and abstracts for relevance based on our predefined inclusion and exclusion criteria. Articles that do not meet the criteria will be excluded at this stage. Second, the remaining articles will be assessed in full text to determine final eligibility. If a full text is unavailable, efforts will be made to retrieve it through institutional access or by contacting the authors.

Disagreements at any stage will be resolved through discussion among the reviewers. If consensus cannot be reached, the decision will be escalated to the full review team for a final vote. Sysrev’s collaborative tools, including real-time reviewer tracking and conflict resolution features, will facilitate this process. A PRISMA flowchart will be generated to document the number of articles retrieved, screened, included and excluded at each stage, along with reasons for exclusion. This will ensure transparency and reproducibility of the screening process. Detailed instructions for screeners are provided and attached in online supplemental appendix 3.

Data extraction

The data extraction process for this scoping review will be conducted systematically using Sysrev. The process will begin with the design of a data extraction form adapted from the JBI framework within Sysrev (see form in online supplemental appendix 4). The form includes fields for study details (such as title, author(s), year of publication and country of study), study characteristics (such as study design, methodology and population characteristics) and key findings (such as food system determinants of seasonal malnutrition categorised at micro, meso and macro levels). Additionally, it includes sections for identifying areas for further research, helping to pinpoint gaps in the existing literature. Before full-scale extraction begins, the form will be piloted by two reviewers using a subset of 5 randomly selected studies from the included articles. Any inconsistencies or ambiguities identified during this process will be addressed through discussion, and necessary modifications will be made to the form before proceeding with full-scale data extraction.

Once the data extraction form is finalised, each included study will be assigned to at least two independent reviewers (see extractor instructions in online supplemental appendix 5). Reviewers will enter extracted data into the predefined fields within Sysrev, following a structured approach that enables tagging, filtering and categorisation of key themes. The tagging feature will allow for the classification of food system determinants based on their level (micro, meso or macro), facilitating a more organised analysis. Sysrev’s automated data extraction assistance will also suggest relevant data points based on previous entries, reducing errors and improving consistency. Sysrev highlights discrepancies between reviewers, enabling real-time tracking of inter-rater disagreements. Where inconsistencies arise, reviewers will engage in discussion to resolve differences. If consensus cannot be reached, a final decision will be made by the full review team through a voting process within Sysrev. Following extraction, data will be exported from Sysrev for further analysis and synthesis.

Analysis and presentation of results

As scoping review scholars recommend, our analysis and presentation of findings will focus on mapping the breadth and depth of evidence rather than assessing quality.^{18 20} The analysis of study characteristics will follow a structured and systematic approach to ensure a clear synthesis of the included studies. The study characteristics will be analysed using descriptive statistics and thematic categorisation to provide an overview of the scope and methodological diversity of the literature on food system determinants of seasonal malnutrition. A summary table will be created to present the frequency of different study designs, geographical focus (eg, rural vs urban) and population characteristics. Where applicable, a qualitative synthesis will highlight recurring themes in study designs, data sources and methodological approaches.

For the key findings, the coding process will be structured according to the FIVIMS framework (see table 1), beginning with predefined categories at micro, meso and macro levels, while allowing for emergent themes. Patterns in how different studies define and measure food system determinants of seasonal malnutrition will be identified. The balance between deductive and inductive approaches is consistent with current best practices in evidence synthesis.¹⁸ Any gaps in the literature, such as under-represented geographical regions or populations, will be highlighted to inform future research directions. This will provide a deeper understanding of how research has explored food system determinants of seasonal malnutrition in children under five in SSA.

Table 1. Food Insecurity and Vulnerability Information and Mapping Systems (FIVIMS) framework for analysing food system determinants of seasonal malnutrition.

Level	Key elements
Micro	Food consumption, energy intake, nutrient intake, consumption status, food utilisation, nutritional status.
Meso	Household food access, infant and young child feeding (IYCF) practices, intrahousehold food distribution, food safety and quality, nutritional knowledge and eating habits.
Macro	Food economy (socioeconomic, political, institutional, cultural and natural environment), food availability (domestic production, import capacity, food stocks, food aid), food stability (weather variability, price fluctuations, political and economic factors), food access (poverty, purchasing power, income, transport and market infrastructure).

Ethics and dissemination

As this review involves analysis of previously published data, ethical approval is not required. Findings will be disseminated through a peer-reviewed publication. The published article will be widely shared on the authors’ social media platforms, including X (formerly Twitter), LinkedIn and ResearchGate, to maximise accessibility and policy uptake of evidence on food system determinants of seasonal child malnutrition in SSA. Results will inform the development of integrated system-based approaches to address seasonal malnutrition in children under five in SSA. The full study protocol, datasets and supplementary forms will be published in an open-access repository in compliance with the Findability, Accessibility, Interoperability and Reuse principles.