Eating insects could help tackle climate change by reducing greenhouse gas (GHG) emissions linked to livestock production, research from the University of Edinburgh suggests.
Replacing half of the meat eaten worldwide with crickets and mealworms would cut farmland use by a third, substantially reducing GHG emissions, the researchers said.
While consumers' reluctance to eat insects may limit insect consumption, even a small increase would bring benefits, the team said. This potentially could be achieved by using insects as ingredients in some prepackaged foods.
Using data collected primarily by the U.N. Food & Agriculture Organization, scientists have compared the environmental impacts of conventional meat production with those of alternative sources of food. It is one of the first studies to do so.
Researchers at the University of Edinburgh and Scotland's Rural College considered a scenario in which half of the current mix of animal products is replaced by insects, lab-grown meat or imitation meat.
They found that insects and imitation meat — such as soybean-based foods like tofu — are the most sustainable as they require the least land and energy to produce. Beef is by far the least sustainable, the team said.
In contrast to previous studies, lab-grown meat was found to be no more sustainable than chicken or eggs, requiring an equivalent area of land but using more energy in production.
The team said halving global consumption of animal products by eating more insects or imitation meat would free up 1.680 billion hectares of land — 70 times the size of the U.K.
Similar land savings could also be made by switching from the current mix of animal products to diets higher in chicken and eggs, the team said. They found that the land required to produce poultry was only marginally greater than for insects and imitation meat.
Lead author Dr. Peter Alexander with the University of Edinburgh's School of GeoSciences and Scotland's Rural College said, "A mix of small changes in consumer behavior, such as replacing beef with chicken, reducing food waste and potentially introducing insects more commonly into diets, would help achieve land savings and a more sustainable food system."
Professor Dominic Moran of the University of York and Scotland's Rural College said, "The environmental challenges facing the global agricultural industry are increasing, and this paper has studied some of the alternative foods that we can introduce into our diets to alleviate some of this pressure."
The research, published in the journal Global Food Security, was supported by the U.K.'s Global Food Security Program and the European Union's Seventh Framework Program. It was carried out in collaboration with Scotland's Rural College, the University of York, the Karlsruhe Institute of Technology and the Centre for Australian Weather & Climate Research.