Climate change on household food security in Sub-Saharan Africa: a systematic review

Related Studies

Research on climate change and household food security in Sub-Saharan Africa has expanded considerably over the past decade, reflecting growing concerns about the region's vulnerability to environmental change. Previous studies consistently report that rising temperatures, irregular rainfall patterns, droughts, and floods negatively affect agricultural productivity, particularly among smallholder farmers. Several scholars have highlighted the resulting impacts on food availability, access, utilization, and stability, which are the four pillars of food security. Recent evidence also suggests that climate-related shocks disproportionately affect women, children, and low-income rural households due to limited adaptive capacity. While adaptation strategies such as climate-smart agriculture, crop diversification, and livelihood diversification have shown promise, their effectiveness varies across different contexts. Therefore, a systematic synthesis of recent studies is necessary to provide a comprehensive understanding of the current evidence and emerging trends in the region.

Climate Change and Agricultural Productivity in Sub-Saharan Africa

Climate change has increasingly undermined agricultural productivity in Sub-Saharan Africa (SSA), where rain-fed smallholder farming dominates food production. Evidence shows that rising temperatures, shifting rainfall patterns, and increased climate variability are reducing yields of staple crops and threatening long-term food security. Abebaw (2025) projects yield declines of 10–20% by 2050 across SSA under current climate trajectories, with maize yields in Ethiopia potentially falling by 15% due to heat stress and irregular rainfall. Omotoso et al. (2023) similarly report consistent declines in sorghum, millet, and cassava production linked to drought and temperature extremes. Stuch et al. (2021) highlight increasing inter-annual yield variability, which destabilizes food supply even when average production is maintained. The economic implications are substantial, with Annan and Schlenker (2023) estimating losses of $0.65–$1.8 billion in Cameroon under 2.5°C–5°C warming scenarios. Ngongolo and Gayo (2024) further note that the COVID-19 pandemic compounded these pressures by disrupting input supply chains and agricultural labor. In response, Beday et al. (2022) emphasize sustainable practices such as intercropping, crop rotation, and conservation tillage as effective mitigation strategies, although adoption remains constrained by poverty and weak extension systems. Overall, the literature consistently demonstrates that climate change is reducing both the quantity and stability of agricultural output in SSA, with severe implications for rural livelihoods and household food security.

Extreme Weather Events, Household Food Access, and Livelihoods

Extreme weather events are major drivers of acute food insecurity across Sub-Saharan Africa (SSA), directly affecting household food access and livelihood stability. Increasing frequency and intensity of droughts, floods, and cyclones disrupt agricultural production, food distribution systems, and rural incomes. Naicker et al. (2025) show that climate shocks in South Africa affect the entire food system, with smallholder vegetable farmers particularly vulnerable due to limited income diversification. Maviza et al. (2025) document severe impacts of Cyclones Idai, Gombe, and Freddy in Mozambique and Zimbabwe, including crop destruction, water insecurity, and heightened household vulnerability. Mosalagae and Moremong (2025) report long-term increases in floods, heatwaves, and droughts in South Africa between 1920 and 2023, each event contributing to rising rural poverty. Oyelaran et al. (2024) find that a 1°C temperature increase significantly reduces crop yields, worsening food availability and price instability. Otieno et al. (2026) estimate that about 65% of cultivated land in SSA is rain-fed, making agriculture highly sensitive to climatic variability. Kofi-Mensah et al. (2025) project worsening food deficits by 2050 due to desertification in the Sahel and Horn of Africa. Osei et al. (2023) further highlight that global shocks, such as the Russia-Ukraine conflict, compound climate impacts by increasing food prices. Collectively, these studies show that extreme weather events significantly reduce household food access and deepen food insecurity across SSA.

Climate Change, Nutrition Security, and Vulnerable Populations

Climate change disproportionately affects nutrition security in Sub-Saharan Africa (SSA), particularly among children, women, and low-income households. Evidence shows that climate variability reduces dietary diversity and increases the risk of undernutrition. Tschakert et al. (2020) find that temperature and rainfall anomalies significantly increase child wasting across 16 SSA countries, linking climate stress directly to poor child growth outcomes. Belay et al. (2022) report persistent inadequate dietary diversity among children aged 6–23 months across 33 countries, driven by poverty, maternal education, and limited market access. Aboagye et al. (2021) further show that adequate dietary diversity reduces risks of stunting, underweight, and wasting by 12–17%, underscoring its protective role. Samman et al. (2024) highlight rising food costs, noting that the average cost of a healthy diet reached 3.57 PPP dollars per person per day in 2021, making nutritious diets unaffordable for many households. Ngidi et al. (2024) emphasize that climate-smart agriculture can improve nutrition outcomes, although evidence remains fragmented. Eyasu et al. (2024) link climate-induced food system changes to rising non-communicable diseases, adding a dual burden of malnutrition. Anand et al. (2024) report that Eastern and Western Africa experience undernourishment rates of about 20%, significantly above global averages. Overall, climate change intensifies nutritional vulnerability by reducing food availability, affordability, and dietary quality across SSA.

Climate Change Adaptation Strategies and Policy Responses for Household Food Security

Adaptation strategies play a critical role in mitigating the impacts of climate change on household food security in Sub-Saharan Africa (SSA). Evidence shows that climate-smart agriculture (CSA), livelihood diversification, and improved farming practices can enhance resilience and food access. Belay et al. (2023) demonstrate that CSA adoption in southern Ethiopia significantly improves household income and food security through increased productivity and reduced climate vulnerability. Gebre et al. (2023) similarly report that farmers using drought-tolerant crops, early planting, and income diversification experience better food security outcomes. Mwiti et al. (2025) find that practices such as home gardening, tree management, and crop diversification improve dietary diversity across SSA, even under climatic stress. Tabe-Ojong et al. (2023) show that CSA adoption in West Africa, including improved seed varieties and organic fertilizers, enhances farm performance and food availability. However, Kone et al. (2024) note that policy integration of adaptation strategies remains weak due to institutional fragmentation and limited funding. Mwangi et al. (2025) further emphasize that gender-inclusive approaches and strong extension services are essential for ensuring equitable access to adaptation technologies. Despite demonstrated benefits, uptake of adaptation strategies remains uneven, particularly among the poorest households. The literature indicates that while adaptation measures significantly improve resilience, their effectiveness depends on supportive policy environments, adequate financing, and inclusive implementation frameworks that prioritize vulnerable rural populations across SSA.

Research Design

A systematic review design guided by PRISMA 2020 was adopted. This approach was appropriate for synthesizing heterogeneous evidence on climate change and household food security across SSA (Mwangi et al., 2025). Unlike narrative reviews, it follows a pre-defined protocol that enhances transparency and reproducibility. The study adopted a realist synthesis perspective to explore not only whether climate change affects food security, but also how and under what conditions these effects occur (Naicker et al., 2025). This was necessary due to the diverse agro-ecological and socioeconomic contexts across SSA. The design allowed inclusion of quantitative, qualitative, and mixed-method studies to provide a comprehensive understanding of the climate–food security nexus.

Search Strategy and Databases

A systematic search was conducted in Web of Science, Scopus, PubMed, ScienceDirect, and Google Scholar due to their wide disciplinary coverage and relevance to climate and food security research (Otieno et al., 2026; Kofi-Mensah et al., 2025). The search covered studies published from January 2020 to December 2024 to capture recent and policy-relevant evidence. Boolean operators (AND, OR) were used across three domains: climate-related terms (e.g., drought, temperature, extreme weather), food security outcomes (e.g., food insecurity, dietary diversity), and geographic scope (Sub-Saharan Africa and its regions). No initial language restrictions were applied, but only English-language studies were included. Reference lists of included studies were also hand-searched to identify additional relevant sources (Ngidi et al., 2025).

Inclusion and Exclusion Criteria

Eligibility was guided by the PICOS framework (Page et al., 2021).

Inclusion Criteria:

Peer-reviewed studies (2020–2024)

Focus on SSA countries

Climate change or variability as exposure

Household-level food security outcomes

Quantitative, qualitative, mixed-method, or systematic reviews

English-language publications

Exclusion Criteria:

Studies outside SSA or before 2020

Grey literature, abstracts, theses, and non-peer-reviewed work

Studies without household-level food security data

Studies not linking food insecurity to climate factors

Duplicates or methodologically unclear studies

Two independent reviewers conducted screening at all stages, with disagreements resolved through discussion or a third reviewer (Otieno et al., 2026).

Data Extraction

A standardized and pilot-tested extraction form was used to ensure consistency. Extracted information included authorship, year, country, study design, sample characteristics, climate variables, food security outcomes, key findings, adaptation strategies, and limitations. Data extraction was performed independently by two reviewers and verified through cross-checking. Discrepancies were resolved by re-examining original studies. Data were organized in spreadsheets and structured around the four pillars of food security: availability, access, utilization, and stability, alongside cross-cutting themes such as gender and adaptation (Otieno et al., 2026).

Quality Assessment

Study quality was assessed using the Newcastle-Ottawa Scale (NOS) for quantitative studies and the Mixed Methods Appraisal Tool (MMAT 2018) for qualitative and mixed-method studies (Mwangi et al., 2025; Otieno et al., 2026). Studies were rated as high, moderate, or low quality based on standardized scoring criteria. Two reviewers conducted assessments independently, with inter-rater agreement evaluated using Cohen’s kappa. Low-quality studies were not excluded but were subjected to sensitivity analysis. Greater weight was given to higher-quality evidence during synthesis.

Data Synthesis

Due to heterogeneity in study designs, settings, and outcome measures, meta-analysis was not performed. Instead, a narrative synthesis approach was used, following established best practices (Ngidi et al., 2025; Naicker et al., 2025). The synthesis involved four stages: initial study summaries, thematic grouping, analysis of patterns and differences across contexts, and assessment of robustness across study quality. Emphasis was placed on contextual factors such as socioeconomic status, gender, agro-ecological variation, and institutional capacity, recognizing their role in shaping climate impacts on household food security across SSA.

Climate Change and Agricultural Productivity: A Deepening Crisis in Food Availability

The review confirms that climate change is significantly undermining agricultural productivity across Sub-Saharan Africa (SSA), reinforcing earlier projections and empirical findings. Omokpariola et al. (2025) estimated cereal yield declines of up to 24% in West Africa by 2090, while Abebaw (2025) projected maize yield reductions of about 15% in Ethiopia. These findings align with IPCC (2022) reports showing a one-third decline in African crop productivity growth since 1961. Similarly, Baptista et al. (2022) found that each 1°C increase reduces agricultural output by about 3 percentage points in developing regions, directly affecting subsistence-dependent households. This review adds finer spatial and crop-specific evidence. Affoh et al. (2022) demonstrated that rainfall positively influences food availability while temperature has a persistent negative effect, highlighting a dual stressor of heat and rainfall variability. Stuch et al. (2021) further emphasized increased yield volatility in smallholder systems, threatening production stability. Diatta et al. (2025) illustrated immediate impacts through El Niño-induced crop failures in West Africa, while Omotoso et al. (2023) confirmed widespread declines across sorghum, millet, and cassava systems. Importantly, Beltran-Peña et al. (2022) contextualised these losses within global climate injustice, showing SSA bears a disproportionate burden despite minimal emissions, reinforcing the need for global policy accountability.

Climate-Induced Erosion of Household Food Access and the Food Price–Poverty Trap

While productivity losses are significant, findings show that climate change most severely affects household food security through reduced food access, primarily driven by price inflation and income loss. Baptista et al. (2022) found that low-income households in SSA spend up to 60% of income on food, making them highly vulnerable to price shocks. This dynamic is intensified in SSA due to weak social protection systems and high climate exposure. Osei et al. (2023) reported that agricultural food prices rose by 34% in 2022 due to overlapping climate shocks, pandemics, and geopolitical disruptions. Gebre and Rahut (2021) confirmed a structural poverty trap where climate shocks simultaneously reduce income and increase food costs, deepening household vulnerability. Maviza et al. (2025) further showed that extreme events such as cyclones not only reduce production but destroy assets, infrastructure, and informal support systems, compounding food access challenges. Naicker et al. (2025) extended this to supply chains, demonstrating that climate shocks affect food availability and affordability even in urban markets. This highlights a shift in the literature from production-centred explanations to system-wide disruptions affecting distribution and market access.

Climate Change, Dietary Diversity, and Nutrition Security of Vulnerable Groups

The review highlights severe nutritional consequences of climate change, particularly among children, women, and resource-poor households. Baker and Anttila-Hughes (2020) projected significant increases in child wasting under continued warming, while Tschakert et al. (2020) confirmed direct links between climate anomalies and malnutrition across SSA. These findings align with broader evidence linking climate stress to reduced dietary quality and micronutrient availability. Belay et al. (2022) showed persistent inadequate dietary diversity among young children, driven by poverty and structural inequalities. Aboagye et al. (2021) quantified the protective role of dietary diversity in reducing stunting, underweight, and wasting. This confirms a clear pathway from climate variability to reduced food variety and subsequent malnutrition. Asibuo and Nchanji (2023) highlighted gendered vulnerabilities, noting women’s dominant role in agriculture but limited access to productive resources. Tapkigen et al. (2024) further extended the discussion to emerging diet-related non-communicable diseases, indicating a growing double burden of malnutrition. These findings suggest that food utilisation is increasingly climate-sensitive and must be treated as a dynamic outcome rather than a static condition in SSA food security frameworks.

Adaptation Strategies and Policy Responses: Evidence, Gaps, and the Last-Mile Problem

The evidence on adaptation strategies demonstrates that interventions such as climate-smart agriculture (CSA), diversification, and improved seed systems can significantly improve food security outcomes. Belay et al. (2023) and Gebre et al. (2023) confirmed that CSA practices enhance income and resilience among Ethiopian households. Similarly, Tabe-Ojong et al. (2023) found positive impacts of improved seeds and fertiliser use across West Africa, while Yiridomoh et al. (2025) reported consistent benefits of CSA technologies across multiple SSA countries. However, the key challenge lies in implementation and accessibility. Kone et al. (2024) identified weak policy integration, financing constraints, and institutional fragmentation as major barriers. Otieno et al. (2026) further noted the exclusion of indigenous knowledge systems, reducing local relevance of adaptation strategies. Akinsemolu (2024) highlighted persistent barriers such as limited awareness and resource constraints among smallholders. Importantly, these constraints disproportionately affect the most vulnerable populations. Ngidi et al. (2025) emphasized that gender-inclusive policies and extension services are essential but underfunded. Mwiti et al. (2024) provided evidence that informal household-level adaptation strategies can improve dietary diversity, suggesting that scalable solutions may already exist within communities. While adaptation evidence is strong, the main gap lies in governance, financing, and equitable delivery to the last mile.

Recommendations

Governments in Sub-Saharan Africa should integrate climate adaptation into agricultural policy with strong institutional coordination and adequate financing. Climate-smart agriculture, including drought-resistant crops, irrigation systems, and soil management, should be scaled up and made affordable for smallholder farmers through subsidies and rural credit access. Gender-responsive extension services are essential to ensure women farmers receive equitable support. Early warning systems should be linked with social protection programmes to enable timely responses to climate shocks. International climate finance must be increased and directed toward vulnerable food systems in SSA. Research should also prioritise improving measurement of food security stability to better capture year-to-year climate impacts on households.

Contribution to Knowledge

This review provides an up-to-date synthesis of evidence (2020–2024) on climate change and household food security in Sub-Saharan Africa using PRISMA 2020 guidelines. It integrates all four pillars of food security, showing how climate impacts are interconnected rather than isolated. It advances understanding of compounding mechanisms linking temperature rise, rainfall variability, price shocks, income loss, and nutrition outcomes. The study consolidates scattered evidence on dietary diversity, child malnutrition, and intergenerational impacts, highlighting underexplored nutrition dimensions. Methodologically, it offers a structured thematic framework for future reviews. Importantly, it identifies a persistent last-mile adaptation gap, showing that effective interventions often fail to reach vulnerable households due to structural and institutional barriers.