A Meta-Analysis of Maize Productivity Trends and Their Relationship to Food Security Outcomes in Kenya

Abstract

Maize is Kenya’s principal staple food, consumed by over 85% of the population, with an annual per capita intake of 98 and100 kg. It provides about 35% of total caloric intake and occupies 48.5% of the nation’s cultivable land, making it central to food security and agricultural development. Despite an average annual production of three million metric tonnes, productivity remains uneven across regions due to semi-arid conditions, climate variability, soil degradation, and limited access to quality inputs. These challenges have led to recurrent food shortages and increased dependence on imports. This study primarily employed a meta-analytic approach, complemented by secondary quantitative time-series analysis within a mixed-methods framework, to evaluate the impact of maize productivity on food security in Kenya. The objectives were to examine trends in maize productivity and consumption, identify key determinants of productivity, assess the relationship between productivity and food security, and review government strategies aimed at improving food security. The study was guided by Malthusian Theory, the Food Availability Decline (FAD) Theory, and Sen’s Entitlement Theory. These frameworks provide a conceptual basis for understanding the linkages between maize production and the four pillars of food security in Kenya. Situated within the pragmatic paradigm, the study adopted Mixed Methods Design. Data were synthesized through meta-analysis and meta-regression of sixteen independent studies and complemented by time-series analysis of national datasets. Qualitative evidence from twenty-eight studies was thematically analyzed using Braun and Clarke’s (2006) framework to contextualize policy and institutional dynamics. Time-series analysis from 2000 to 2024 revealed that maize productivity has remained largely stagnant at an average of 1,629 kg/ha, with production growth driven mainly by land expansion rather than yield gains. The meta-analysis from 2014 to 2024 produced a pooled mean maize yield of 3.07 t/ha (95% CI: 2.27–3.86 t/ha), substantially higher than the national smallholder average but marked by high heterogeneity (I² = 99.94%). Meta-regression identified fertilizer use (β = 834.18, p < 0.01) and farm size (β = 1,191.52, p < 0.001) as significant predictors of yield, while rainfall had no significant effect. A weak negative correlation between maize productivity and undernourishment (r = –0.035) suggested a marginal reduction in food insecurity with higher productivity. Thematic analysis highlighted that the National Fertilizer Subsidy Program (NFSP) improved input access but faced challenges of poor targeting, logistical inefficiencies, and elite capture, while digital e-voucher systems improved transparency but had limited reach. The study concludes that maize productivity remains a pivotal driver of food security in Kenya but is constrained by structural, institutional, and ecological barriers. It recommends enhancing fertilizer subsidy targeting, scaling up digital input distribution systems, strengthening agricultural extension, and investing in post-harvest infrastructure. Future research should assess the sustainability of fertilizer use, and explore gender and youth participation, as well as regional comparative analyses to identify scalable pathways for improving maize-based food security in East Africa.