Skip to content

Study: Lack of clean drinking water linked to increased food insecurity

Close-up of a hand held under a brass outdoor water tap as a small stream of water drips into the palm, with a blurred green background.

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. (Photo: iStock)

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.” 

Bar chart titled “Lack of Clean Water Tied to Food Insecurity Around the World.” The chart compares the share of respondents lacking food who either lacked clean drinking water (red bars) or did not lack clean drinking water (blue bars). Globally, 38% of those who lacked food also lacked clean water, compared with 8% who did not lack clean water. By income level, food insecurity is highest among people lacking clean water in low-income countries (61%), followed by lower-middle-income countries (50%), while rates are lower in upper-middle-income (22%) and high-income countries (18%). By region, the highest rates among those lacking clean water are in Eastern Africa (64%), Central/Western Africa (55%), and South Asia (54%). The lowest rates are in Eastern Europe (6%), East Asia (9%), and Northern/Western Europe (9%). Across all regions and income levels, food insecurity is consistently more common among people who lack access to clean drinking water. Source: World Risk Poll of 121 countries.

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.