Unsafe food causes an estimated 866 million illnesses and 1.5 million deaths annually worldwide, according to new data from the World Health Organization (WHO).
This underscores the often-overlooked toll of contaminated food on health, development, and fragile economies.
The new insights, released on Wednesday ahead of next week’s World Food Safety Day (WFSD) on June 7, show that children under five are particularly vulnerable.
Unsafe food is any food that may cause illness, injury, or harm when consumed. It is typically contaminated by biological (bacteria, parasites), chemical (toxins, heavy metals), or physical (glass, metal) agents.
These hazards can cause conditions ranging from mild diarrhea to severe, life-threatening illnesses. Although children under five make up only nine percent of the global population, they suffer nearly one-third of all foodborne diseases, many of which are severe diarrheal illnesses that can be fatal, according to the WHO.
Exposure to chemicals like lead and methylmercury through food can also damage developing brains and cause lifelong neurological and developmental problems in children.
“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 full picture of its staggering human and economic toll. These new estimates change that,” WHO Director-General Tedros Ghebreyesus said.
The study found that foodborne bacteria, viruses, and parasites caused most illnesses—about 860 million cases in 2021 alone. However, chemical contamination was responsible for the majority of deaths linked to unsafe food.
According to the WHO, chemical hazards accounted for 73 percent of food-related deaths in 2021. Inorganic arsenic and lead were the leading contributors, as prolonged exposure increases risks of heart disease and cancer. Together, these substances were linked to over one million deaths in a single year.
Food can become contaminated through unsafe water, improperly handled products, or toxins entering the food chain via environmental pollution and industrial activities. Once chemicals like arsenic, lead, or methylmercury enter the food supply, they are often difficult or impossible to remove.
WHO states that Africa and Southeast Asia account for nearly three-quarters of all foodborne illnesses and 60 percent of global deaths. Children and those in low-resource communities face the greatest risks, highlighting ongoing inequalities in food systems, healthcare, and sanitation.
WHO estimates that foodborne diseases caused around $310 billion in lost productivity in 2021 due to time off work. Adjusted for cost of living differences, economic losses rise to about $647 billion.
“This report is a wake-up call – but also a roadmap,” said Yuki Minato, a WHO technical officer for food safety and senior author of the study published in The Lancet Global Health. “The data show that foodborne diseases are not only persistent but are worsened by climate change, which increases contamination risks, and by antimicrobial resistance, which makes infections harder to treat. We cannot tackle these threats alone.”
WHO emphasizes that the findings should help countries target interventions, strengthen surveillance, and improve cooperation across health, agriculture, and environmental sectors.
“Delay costs lives,” Minato warned.
