The World Health Organisation says contaminated food causes 1.5 million deaths and 866 million illnesses every year, a staggering toll that disproportionately strikes the world's poorest people.
The WHO released these figures on Wednesday ahead of next week's World Food Safety Day on June 7. The data reveal what health officials have long suspected but never fully quantified: that foodborne diseases rival major killers in their impact on global health and economies.
Children under five bear the heaviest burden. Although they make up just nine per cent of the world's population, they account for nearly one-third of all foodborne illnesses, often severe diarrhoeal diseases that prove fatal. Exposure to chemicals like lead and methylmercury through contaminated food can also damage developing brains and cause lifelong neurological problems.
Unsafe food contains biological hazards like bacteria and parasites, chemical contaminants like heavy metals, or physical objects like glass and metal. What causes most illnesses differs sharply from what causes most deaths. Foodborne bacteria, viruses, and parasites accounted for about 860 million cases in 2021, yet chemical contamination was responsible for most deaths. Inorganic arsenic and lead alone were linked to more than one million deaths in a single year, largely because prolonged exposure increases the risk of heart disease and cancer.
WHO Director-General Tedros Ghebreyesus said the new estimates fundamentally change how the world must respond. "Food safety is not an abstract issue," he said. "It touches every meal, every family, every day. Unsafe food has always been a major public health concern, but until now, we lacked the bigger picture of its staggering human and economic toll. These new estimates change that."
Africa and Southeast Asia bear the brunt. The two regions account for nearly three-quarters of all foodborne illnesses and 60 per cent of global deaths from contaminated food. Children and people living in low-resource communities face the greatest risks, reflecting persistent inequalities in food systems, healthcare access, and sanitation.
Food becomes contaminated through unsafe water, improperly handled products, or toxins entering the food chain through environmental pollution and industrial activities. Once chemicals like arsenic, lead, or methylmercury contaminate the food supply, they are often difficult or impossible to remove. Climate change is worsening the problem by increasing contamination risks, while antimicrobial resistance makes infections harder to treat.
The economic cost is staggering. The WHO estimates foodborne diseases resulted in around 310 billion dollars in lost productivity in 2021 due to time away from work. Adjusted for differences in the cost of living between countries, the economic losses rise to an estimated 647 billion dollars, roughly equivalent to 240 trillion naira at current exchange rates.
Yuki Minato, a WHO technical officer for food safety and senior author of the study published in The Lancet Global Health, called the findings both a warning and a guide. "This report is a wake-up call, but also a roadmap," he said. "The data show that foodborne diseases are not only persistent but are being made worse by climate change, which increases contamination risks, and by antimicrobial resistance, which makes infections harder to treat. We cannot tackle these threats alone. Delay costs lives."
The WHO said countries must use these findings to target interventions, strengthen surveillance systems, and improve cooperation across health, agriculture, and environmental sectors. The organisation will push for coordinated global action during World Food Safety Day celebrations next week.
