Children aged less than five years face almost three times the risk of illness from unsafe food than older children and adults, according to new estimates released today by the World Health Organization (WHO).
Despite being just 9% of the global population, young children suffer from nearly one third of all cases of foodborne diseases, particularly diarrhoeal diseases which can be deadly for this vulnerable age group. In addition, exposure to chemical hazards such as methylmercury and lead in food can harm the developing brain and cause lifelong neurological and developmental problems in children.
WHO estimates that unsafe food causes around 866 million illnesses and 1.5 million deaths annually, many of which could be prevented with measures including improved water, sanitation and hygiene, food safety practices such as pasteurization and access to health care for vulnerable populations. Although the total foodborne disease burden has declined since 2000, major regional inequalities persist, with the greatest burden in Africa and South-East Asia.
Exposure to biological hazards, including foodborne bacteria and viruses as well as parasitic infections, caused the majority of foodborne illnesses (approximately 860 million in 2021), while chemical exposures drove a disproportionate share of deaths. In 2021, chemical hazards accounted for a striking 73% of deaths due to contaminated food. Most of these chemical-related deaths were linked to inorganic arsenic (42%) and lead (31%), largely because these exposures increase the risk of heart disease and cancers.
Beyond health impacts, the study estimates that in 2021 foodborne disease led to about US$ 310 billion in lost productivity (time away from work due to illness). When the economic impact was adjusted for cost-of-living differences between countries, the estimate increased to US$ 647 billion in lost productivity.
“Food safety is not an abstract issue – 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.” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General. “For the first time, countries have their own data to see where the burden is highest. With that knowledge, governments can prioritize the actions needed to protect people’s health.”
Expanded scope, sharper picture
WHO’s new analysis significantly expands the evidence base by assessing 42 major foodborne hazards, including bacteria, viruses, parasites and chemicals, from 194 countries from 2000 to 2021. The estimates now include new hazards including metals, rotavirus, and Trypanosoma cruzi (the parasite that causes Chagas disease).
Food can be contaminated with chemicals such as inorganic arsenic, lead and methylmercury from natural sources and human activities. Once these substances have entered the food chain, they are often difficult or impossible to remove. WHO calls on governments to prevent contamination at the source – through better agricultural practices, stricter industrial controls and stronger environmental regulations.
While the presence of some metals in food has been decreasing over time, these estimates reveal for the first time the burden of cardiovascular diseases, cancers, and intellectual disability resulting from dietary exposure to metals. Inorganic arsenic and lead are linked to more than 1 million deaths in one year; methylmercury can harm the developing brain and cause lifelong neurological and developmental problems in children.
A crisis of equity
Evolving diets, environmental pressures, globalization and inequalities in food systems continue to shape who is most exposed to unsafe food. Children and people living in low-resource communities experience the greatest health burden, particularly in low- and middle-income countries. The African and South-East Asian regions together account for nearly three-quarters of all foodborne illnesses and 60% of global deaths. “This report is a wake up call – but also a roadmap. 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,” said Yuki Minato, WHO technical officer for food safety and senior author of The Lancet Global Health paper. “A One Health approach – integrating human, animal, plant, and environmental health – is essential. Countries must act urgently, using these estimates to target interventions, invest in surveillance, and break down the silos between health, agriculture and environment sectors. Delay costs lives.”
