Quantifying the impact of diet quality on hunger and undernutrition

Food and nutrition security has been a persistent major challenge to human societies and this challenge continues into the 21st century, especially taking into consideration the targets set by the UN Sustainable Development Goals, which call for eradicating hunger (goal 2), ending poverty (goal 1), sustainably managing and using natural resources and ecosystems (goal 15), and combating climate change (goal 13). The way food is consumed and produced affects the human well-being as well as the environment. Avoiding food losses and adopting a balanced healthy diet is also an important step towards sustainability. Promoting dietary standards and monitoring their adoption is a potentially important policy tool for mitigating environmental impacts of food production as well as monitoring food security and nutrition. There is relatively little research to measure nutritional adequacy of food intake according to dietary standards, and to explore the relationship with health outcomes. In this study we choose the well-established WHO global level dietary recommendations as a reference to quantify nutritional adequacy by developing an energy and macronutrient intake index (ENI), and to assess its relation to indicators of hunger and undernutrition. We find strong negative association between nutritional adequacy of dietary intake and prevalence of undernutrition at the national level, and we illustrate that ENI could be an effective tool to inform national food security strategies. Under different future socioeconomic development scenarios, almost all sub-Saharan African countries achieve an adequate per capita energy intake level but their nutritional status varies with many countries deviating from recommended levels because of the unbalanced development of macronutrient intake levels; more improvement exists in fat and energy intake levels and less agreement in fruit vegetable and animal protein intake levels. Scenario application proves that the relationship between ENI and undernutrition could readily be applied in future scenarios generated by integrated assessment models to provide insights into the impacts of various climate change scenarios, socioeconomic development pathways and alternative global trade policies on global hunger and undernutrition status