Our global food system is failing to meet nutritional needs and concerns are growing about health related to under- and over-consumption as well as severe nutrient deficiency. The United Nation’s second sustainable development goal (SDG2) targets the end of malnutrition in all forms by 2030. Now, new research has shown that, to meet this target, we would need a different approach to assessing nutrient sufficiency of the global food system.
This study, published in Frontiers in Sustainable Food Systems, is the first to quantitatively map the flow of energy, protein, fat, essential amino acids and micro-nutrients from ‘field-to-fork’, at a global level. This has allowed for the evaluation of sufficiency of nutrient supply and identification of key hotspots within the global food supply chain which could be targeted for improved efficiency. The research brings to light the complexities that arise in delivering a balanced food system which can only be handled by a holistic approach.
“There are two main issues with how we currently talk about food systems,” says Hannah Ritchie, a research assistant from the University of Edinburgh, who led the study. “The first is that we focus our measure of food security in terms of calories (energy), when micro-nutrient malnutrition (‘hidden hunger’) affects more than 2 billion people across the world.”
She further adds, “The second issue is that aspects of our food system are reported in tonnes or kilograms, and it’s very hard to put these numbers in the context of how many people this could feed. We wanted, for the first time, to assess the full food system in useful metrics - average nutrients per person - across all the nutrients that are essential to good health.”
Using food balance and nutrient composition datasheets from the UN Food and Agriculture Organization (FAO), the researchers were able to quantify digestible protein, fat, calories, amino acids and micro-nutrients across the supply chain—from crop production to food delivered to households. FAO’s regional waste data was used to calculate food and nutrient losses and all metrics were normalised to an average per person per day (pppd). Nutrient supply values were compared to average nutritional requirements to assess whether they would be sufficient by the time food arrives at the household level. Surprisingly, the researchers found that all nutrients, not just calories, exceed average requirements.
“Previous studies have shown that we produce much more than we need in terms of calories (5,500—6,000 kCal pppd), but I was not expecting this for protein and essential micro-nutrients. Some nutrients were up to five times the average requirement,” explains Ms Ritchie. The research shows that even though all nutrients exceed requirements, food wastage and nutrient losses in the supply chain mean that by the time some nutrients reach households, they barely scrape by. “This would be okay in a perfectly equitable food system,” Ms Ritchie explains, “but with large inequalities in food availability, we know that many people will be deficient in several essential nutrients.”
The problem is further complicated as not all stages of loss are the same for every nutrient. For instance, the data shows that the largest losses of many micro-nutrients (vitamin A, vitamin C, folate and calcium) occur in post-harvest waste of fruits and vegetables, while the largest losses of energy and protein occur in allocation of crops to animal feed and bio-fuel. “This is important information to understand,” says Ms Ritchie “Knowing that the highest-impact interventions for maintaining micro-nutrients may not be the same as for calories, which may not be the same as for protein, will help to focus our efforts for food security and nutrition.”
The study further points out complicated trade-offs in the production of meat and dairy. Ms Ritchie explains, “When you consider that more that 80% of farmland is used for grazing or animal feed production, livestock are clearly an inefficient way of producing food. But, while livestock are an inefficient converter of feed, they remain the only natural dietary source of vitamin B12 and an important source of high-quality protein and lysine (an amino acid) for many people.”
Overall, this new study has provided a high-level framework that can inform policy decisions on global food security and show where to target efforts for improved sufficiency and possible trade-offs that may arise. Although the framework is limited by the resolution of data used, i.e., its inability to capture regional or local dynamics, the researchers still advocate its usefulness.
Praising the framework, Professor David Reay, a supporting researcher from the University of Edinburgh, said, “This study is just the start. In the future, this replicable framework can be used to map food pathways for specific regions and countries. Our hope is that governments and development agencies can use it to assess food security risks and develop locally specific solutions.”
This study has started the process of first understanding the complexity of ensuring a balanced food system and then implementing a better approach to meet future food targets. “With population growth, intensifying climate change impacts and rapidly changing diets, the need for evidence-based, holistic assessments of our food system have never been more urgent,” advises Professor Reay.
