More than 866 million people fell ill and 1.52 million died from foodborne diseases in 2021, according to updated World Health Organisation estimates that paint a stark picture of the global toll of contaminated food.
The assessment, which examined 42 infectious and chemical foodborne hazards across countries and regions, found that unsafe food was responsible for 57.1 million disability-adjusted life years (DALYs), a measure that combines years lost due to illness, disability and premature death. The burden was found to be greatest in Africa and South-East Asia.
The findings show that foodborne disease remain one of the world’s major public health challenges despite an overall decline in burden since 2000. Researchers said the scale of the problem is comparable to that of tuberculosis, HIV/AIDS and malaria, underscoring the continuing health and economic costs of unsafe food.
The study found that while foodborne illnesses are often associated with infections, chemical contaminants accounted for a disproportionate share of deaths. Inorganic arsenic and lead emerged as the leading contributors to the overall burden, alongside non-typhoidal Salmonella. Chemical hazards were linked to nearly three-quarters of all deaths caused by contaminated food, despite accounting for only a small fraction of total foodborne illnesses.
Children bore a particularly heavy burden. The incidence of foodborne illness among children under five was 2.7 times higher than among older age groups, while their rate of health loss measured through DALYs was 4.3 times greater. The findings highlight the continued vulnerability of young children to contaminated food and its long-term consequences.
Researchers estimated that the 42 hazards studied caused 866 million foodborne illnesses worldwide in 2021. Of these, diarrhoeal diseases accounted for the largest share, followed by invasive enteric and parasitic diseases. The study also found major inequalities between regions, with the highest rates of illness and disease burden concentrated in parts of sub-Saharan Africa, the Horn of Africa and South-East Asia.
Beyond its health impact, unsafe food was found to carry a substantial economic cost. Productivity losses linked to foodborne disease were estimated at US$310 billion in nominal terms in 2021, rising to $647 billion after adjusting for purchasing power parity.
Although the overall burden has declined over the past two decades, researchers said significant disparities remain across regions and populations. The findings point to the continuing challenge of ensuring safe food supplies and reducing exposure to both infectious and chemical hazards worldwide.
