International food trade, accounting for approximately a quarter of all food produced for human consumption, is generally viewed as enhancing food availability, access, and diversity. While potential benefits like increased food security and efficient resource use are acknowledged, concerns exist regarding the environmental consequences (outsourcing pollution) and health implications (altered dietary patterns, rising obesity). Existing research often correlates general health markers with trade liberalization or specific trade agreements, or describes the impact of trade on calorie and nutrient distribution. However, few studies directly link food trade to dietary risks and associated diseases. This study addresses this gap by quantifying the proportion of dietary risks and diet-related mortality attributable to international food trade, focusing on key dietary risks: insufficient consumption of fruits, vegetables, legumes, and nuts, and excessive red meat consumption. These risks are major contributors to non-communicable diseases (NCDs) like heart disease, stroke, cancer, and diabetes, collectively responsible for a substantial global disease burden. By linking dietary risks to international food trade, the study aims to identify the role of food imports in the dietary health of importing countries and assign responsibility to exporting countries. This demand-driven attributional perspective informs the development of health-sensitive food, trade, and agricultural policies, particularly relevant given potential trade disruptions from various factors (Brexit, climate change-related disasters, armed conflicts).

The research acknowledges existing studies that have examined the relationship between trade and health, highlighting two main approaches. The first approach focuses on correlations between general health markers (life expectancy, BMI) and trade liberalization or specific trade agreements using statistical or economic models. The second approach describes the contribution of international trade to the distribution of calorie and nutrient availability. However, a significant gap identified by the authors is the lack of research directly connecting food trade to dietary risks and related diseases. This study differentiates itself by directly quantifying the contribution of food trade to these risks and the resulting mortality.

The study utilizes detailed bilateral trade data from the Food and Agriculture Organization of the United Nations (FAO) for 2019. This data is based on the International Merchandise Trade Statistics methodology, incorporating data from various national authorities and employing statistical models to address data gaps and non-reporting countries. A balancing algorithm, based on input-output accounting and incorporating production data of primary and secondary food products, is used to link food consumption to primary production and track the contribution of food exports from one country to national consumption in another. Established risk-disease relationships from meta-analyses of epidemiological cohort studies are used, along with mortality rates and population numbers, to estimate the proportion of diet-related diseases and mortality attributable to traded foods. The algorithm accounts for food waste at the household level. The study's attributional approach, similar to input-output assessments of embodied environmental impacts in trade, quantifies the proportion of dietary risk increases or decreases in each country attributable to imported foods, identifying the countries of origin and extending the attribution of positive or negative dietary-health impacts to those countries. The analysis differs from economic analyses of trade scenarios that include economic feedbacks and scenario analyses focusing on comparing trade versus no-trade scenarios or quantifying market changes to trade interventions. Instead, the focus is on attributing the proportion of dietary risk and disease burden to imported foods.

The analysis reveals that over 190 million tonnes of foods related to dietary risks (3–12% of production) were exported internationally in 2019. This included significant quantities of fruits, vegetables, legumes, nuts, and red meat. Most fruits, legumes, and nuts originated from the Americas, vegetables from Asia, and red meat from Europe. Food imports contributed considerably to national food availability (3–31 grams per person per day, 5–21% of demand), varying significantly across regions. Europe showed the highest reliance on imports. Importantly, the trade-related contributions to food intake, after adjusting for food waste, resulted in a net reduction of 1.2 million diet-related deaths globally (95% CI: 0.8–1.7 million). Fruits contributed to the largest reduction in mortality, followed by vegetables, nuts, and legumes. In contrast, red meat imports were associated with an increase of 147,000 deaths. Over half of the avoided deaths were due to reduced coronary heart disease, with stroke and cancer also significantly affected. Europe was the largest net beneficiary of this trade, primarily through imports of fruits and vegetables, followed by Asia and the Americas. The Americas were the largest contributors to global reductions in diet-related mortality through exports. At the country level, most importing countries (152 out of 153) experienced net health benefits, with the United States, Russia, Germany, China, and the United Kingdom among the largest beneficiaries. Papua New Guinea was the only country with a net increase in mortality due to trade. Among exporting countries, most (90%) contributed to mortality reductions, primarily China, the United States, Brazil, Spain, and Turkey. However, some countries, like Germany and Denmark, contributed to mortality increases through red meat exports. The net change in mortality attributable to food trade represents approximately 19% of the total diet-related health burden.

This study significantly advances research on health and trade by directly linking food trade to final health outcomes (mortality), resolving trade patterns instead of relying on trade openness indices, and providing country-level analysis for all participating countries. The methodology offers advantages over existing regression analyses in terms of time and context dependency, and flexibility for future applications. The findings highlight both positive and negative roles of food trade in health. While trade in health-promoting foods generally contributes positively, especially for regions with substantial imports, exceptions exist, particularly with red meat exports. The study acknowledges limitations, including a focus on major dietary risks (excluding the impact on overweight/obesity and ultra-processed foods), and acknowledges that the risk-disease relationships used are based on assumptions (causal associations, residual confounding). The study's findings provide a valuable health perspective to the existing literature on the environmental and social impacts embodied in trade flows. Unlike the existing literature, which typically shows that environmental and social impacts affect exporting countries, this study finds that health impacts predominantly affect importing countries, with developed countries disproportionately benefiting from importing health-promoting foods from less developed countries. Similar to previous work, however, the study found that the embodied impacts are not preserved between exporting and importing regions due to differences in mortality rates and baseline consumption. The authors propose this highlights the need for further research concerning ultra-processed foods and their relationship to trade.

This study demonstrates the substantial contribution of international food trade to dietary risks and mortality, with both positive and negative effects depending on the type of food. The findings underscore the need for health-sensitive policies that promote trade in health-promoting foods while mitigating the negative impacts of unhealthy food trade. Future research should investigate the broader impacts of food trade on health, including obesity and ultra-processed food consumption, and explore the long-term implications of trade disruptions.

The study focused primarily on major dietary risks and did not fully consider other health aspects such as the impact of food trade on overweight and obesity, or the consumption of ultra-processed foods. The analysis is also subject to limitations inherent in comparative risk assessments and nutritional epidemiology, primarily concerning the assumptions made about the causal nature of the risk-disease relationships used. Residual confounding with unaccounted risk factors cannot be entirely ruled out. Finally, while the data and methods presented are comprehensive, additional research focusing on other aspects related to food trade is recommended to broaden understanding and improve policy guidance.