The Epidemiology of the Global Syndemic in Africa: New Evidence and Key Insights

Over the past decade, Sub-Saharan Africa has entered a new phase in the evolution of the global syndemic of undernutrition, obesity, and climate change. Earlier reviews, largely based on evidence before 2018, documented the emergence of overlapping nutritional and environmental vulnerabilities. This review provides an updated synthesis of epidemiological evidence published between 2019 and 2025 to capture recent shifts in magnitude, distribution, and interactions of the syndemic components across Africa. Recent data indicate that adult obesity prevalence in the African region reached 12% in 2022, rising from 9% in 2010, with marked sex differences of approximately 17% among women and 7% among men. Overweight and obesity among children and adolescents remain lower but are increasing, with an estimated three million children affected in 2022. At the same time, undernutrition remains highly prevalent. Between 2019 and 2025, child stunting ranged from 9% to 46%, wasting from 4% to 43%, and anaemia from 19% to 61% across countries in the African region. Food insecurity increased from 17% in 2019 to 20% in 2025, affecting approximately 282 million people. During the same period, climate-related shocks intensified. Extreme weather events affected 34 million people in Africa in 2023 alone, further disrupting food systems, reducing dietary diversity, and reinforcing reliance on energy-dense, nutrient-poor diets. Evidence now more clearly demonstrates that undernutrition, obesity, and climate stressors co-occur within the same populations and households, rather than representing sequential transitions. This update highlights advances in surveillance, analytical methods, and early warning systems since 2019, while identifying persistent gaps in longitudinal data, integration of nutrition and climate information, and policy implementation. Addressing the contemporary global syndemic in Africa requires context-specific, multisectoral strategies that prioritise double- and triple-duty actions to simultaneously reduce nutritional and climate vulnerability.