I have been going through old papers and this one from 2018 is a banger, and highly relevant to the current tariff wars. The paper examined how international food trade influences the global distribution of nutrients. Instead of focusing only on food quantity, we assessed whether trade helps countries meet macro- and micronutrient needs, and what happens under a no-trade scenario. Our central question was to determine whether trade improves nutritional equity across countries and what risks protectionist trade policies pose to food security.

Three Key Findings:

1. Global adequacy exists—but is unevenly distributed.

If nutrients were equitably distributed, current global food supply could meet average dietary needs for all major nutrients, with huge surpluses for protein and vitamin B12. However losses due to waste, conversion, and unequal distribution mean that many countries fall short, especially for micronutrients like folate and iron.

2. Trade improves nutrient equity, especially for poorer countries.

International trade reduces inequality in nutrient distribution. Without trade, disparities would be much higher, and between 146–934 million fewer people could be potentially nourished, depending on the nutrient. Low-income countries generally obtain access to nutrients through trade, except for iron and folate. The map below shows the change in the number of people who could be nourished without trade. For each country, the number of people (in millions) who could be nourished under current (average of 2007–2011) scenarios was subtracted from the number of people who could be potentially nourished under a no-trade scenario. Map breaks correspond to minimum, first quantile, medium, third quantile, and maximum for each nutrient.

3. Protectionist policies threaten nutrition security.

While trade is not perfect—since traded foods are often low in micronutrient content and not equally accessible to the poor—it still plays a critical role in helping countries meet nutrient needs. For some critical micronutrients—like iron and folate—trade does not consistently improve availability, and in some cases makes it worse. This highlights both the benefits and vulnerabilities of relying on global markets for nutrition but also, restricting trade would likely worsen global undernutrition and inequality in access to key nutrients.

Check out the paper here.