LOS ANGELES – June 2, 2026 – A new global study has found that people without access to clean drinking water are significantly more likely to experience food insecurity and food safety threats, underscoring the urgent need for coordinated global action to address these issues together.
The study was published in Nature Food by a team of researchers from the University of Southern California (USC) and the International Water Management Institute (IWMI) with expertise in water, food, and public policy. They analyzed survey data from the Lloyd’s Register Foundation World Risk Poll , which included 124,003 respondents from 121 countries across all country-income levels.
The data revealed that, around the world, people who lack clean drinking water also tend to have difficulties with food access and food safety.
“Even if you live in a wealthy country, if you lack access to clean drinking water, you are more likely to lack access to food,” said Wändi Bruine de Bruin , lead author of the study. Bruine de Bruin is Provost Professor of Public Policy, Psychology, and Behavioral Science at the USC Price School of Public Policy, and Director, Behavioral Science and Policy Initiative, at the USC Schaeffer Institute for Public Policy & Government Service.
Coordinated Action Required
Researchers say the results demonstrate why governments, humanitarian organizations, and public health leaders should address water and food insecurity together rather than as separate issues.
"Water insecurity, food insecurity, and food safety are too often siloed as distinct challenges — and mistakenly presumed to be burdens borne only by low- and middle-income nations,” said Rachael McDonnell, Deputy Director General, International Water Management Institute, and one of the study’s co-authors. “Addressing this interconnected crisis demands that global, national, and local institutions transcend the structural and political barriers that have long fragmented coordinated action across the water-food nexus.”
The researchers suggest several reasons why people who lack clean drinking water also experience problems with accessing safe and sufficient food:
Problems with water and food might be caused by environmental factors, such as poor infrastructure, climate change, poverty, homelessness, and war;
Without clean drinking water, it is difficult to prepare food safely, if at all; and
Spending more money and time on getting food means spending less money and time on getting clean water.
Proposed Solutions
The study calls for expanded investments in clean water infrastructure, sanitation systems, and community-based public health programs, particularly in vulnerable and underserved regions. Researchers also encouraged policymakers to strengthen collaboration across water, food and other sectors to better address overlapping challenges.
Public health experts warn that climate change, population growth, and increasing pressure on water resources could intensify these risks in the coming decades. Drought, extreme weather, and declining freshwater supplies may make both water insecurity and food insecurity more common, particularly in low-resource communities.
The findings add to a growing body of evidence showing that access to clean drinking water is fundamental not only for health and sanitation but for nutrition, food safety, and economic stability.
Researchers hope the study will encourage policymakers and international organizations to prioritize comprehensive strategies that protect both water and food systems.
“Access to clean drinking water is a basic human necessity,” the study concluded. “Ensuring safe water access is critical to improving food security, reducing health risks, and supporting healthier communities worldwide.”
The other researchers were:
Joshua Inwald, Dornsife College Department of Psychology at the University of Southern California;
Sera Young, Center for Water, Northwestern University; Professor, Department of Anthropology and Program in Global Health Studies, Weinberg College of Arts and Sciences; Co-Director, Center for Water; and Morton O. Schapiro Faculty Fellow, Institute for Policy Research, Northwestern University
Kayla de la Haye, Fielding School of Public Health, University of California, Los Angeles.
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Nature Food
Survey
People
A lack of clean drinking water is associated with lacking food and experiencing food safety threats in 121 countries across the globe
1-Jun-2026
We acknowledge funding from the Lloyd’s Register Foundation as part of the World Risk Poll into Action funding call (grant no. TWRP\100007; principal investigator: W.B.d.B.), the National Science Foundation (2125616; principal investigator: K.d.l.H.), as well as the Leverhulme Trust Foundation, the Reckitt Global Hygiene Institute and the Innovative Methods and Metrics for Agriculture and Nutrition Action (IMMANA) program, which is led by the London School of Hygiene & Tropical Medicine, in partnership with Tufts University and the University of Sheffield, and which is co-funded with UK International Development from the UK government and by the Gates Foundation (INV-002962/OPP1211308; principal investigator: S.L.Y.). The World Risk Poll was launched by the Lloyd’s Register Foundation, in collaboration with Gallup. The funders had no role in our conceptualization, data analysis, decision to publish, or preparation of the manuscript. We thank C. Monder at the University of Southern California’s Public Exchange for project management.