Currently, roughly a third of cereal crop production is fed to animals, and about a quarter of captured fish aren’t used to feed people.
A researcher dedicated to global water and food issues has devised a simple way to increase the global food supply to feed about 1 billion more people without increasing natural resource use or implanting major dietary changes.
Aalto University’s Matti Kummu and his team recently published a study in Nature Food that shows how adjustment to the feeding of livestock and fish could maintain production while providing calories for up to 13% more people.
Previous research from Kummu’s group on reducing food loss throughout the supply chain—from production, transport and storage to consumer waste—showed an increase in food supply by about 12%.
“Combined with using by-products as feed [in the current study], that would be about one-quarter more food,” said the associate professor, who is part of the university’s water and development research group.
The study focuses on the inefficiency of the current structure of the global food system that sees up to 40% of all arable land and more than 30% of cereal crop production used for animal feeds only. Additionally, approximately 23% of all captured fish are destined for non-food uses, mainly fish and livestock feeds, as well.
First, the researchers gathered data on both feed material flows and the availability of food system by-products and residues at a level of detail that did not previously exist. They then analyzed the potential of replacing food-competing feedstuff—including cereals, whole fish, vegetable oils and pulses that account for 15% of total feed use—with food system by-products and residues.
The team found that reducing the feed use of cereals presents the highest potential for increasing the global food supply. However, the increased supply of whole fish, pulses and oilseed oils can also contribute substantially to human nutrition, especially in terms of protein and fat.
According to the study results, with these changes implemented, 10 to 26% of total cereal production and 17 million tons of fish (~11% of the current seafood supply) could be redirected from animal feed to human use. Depending on the precise scenario, the gains in food supply would be 6 to 13% in terms of caloric content, and 9 to 15% in terms of protein content.
“That may not sound like a lot, but that’s food for up to about 1 billion people,” said first author Vilma Sandström, a postdoctoral researcher in the water and development research group at Aalto.
Better utilizing food by-products and residues affects more than just food output. It has been shown to reduce environmental pressure on arable land and freshwater ecosystems, as well as reduce greenhouse gas emissions and fertilizer application. It can also be more cost-effective since many by-products and crop residues as widely available, low-cost materials.
Although the authors say these changes are simple, society has experienced much backlash when it comes to food for human consumption. That could be a problem as the human-edible food currently used in livestock production and aquaculture is different from the food consumers are familiar with. For example, a different variety of corn is used in feed industries and some of the grains are lower quality, while the fish used in fishmeal production tend to be small, bony fish that aren’t popular with consumers.
Sandström and Kummu acknowledge that overcoming these hurdles would require adjustments in the supply chain, but says the benefits far outweigh the costs.
“I don't think there’s any serious problem with doing this,” said Jummu. “What we’re suggesting is already being done on a certain scale and in some areas, so it’s not something that would have to be developed from scratch. We just need to adjust the current system and increase the scale of those practices.”