Scientists To EU: Grow More Legumes For Sustainable & Nutritious Food System

Producing more beans, peas and lentils offers a far more sustainable and nutritious approach to European agriculture, scientists say in a new study. According to the research, adding legumes to traditional crop rotations can significantly reduce the use of pesticides and fertilisers, slashing emissions in line with the European Green Deal, while promoting a transition to healthier diets. 

Scientists are calling for more legumes to be grown in Europe in order to build a healthier and climate-friendly food system. The study, published in Frontiers in Sustainable Food Systems, represents one of the first investigations into the potential benefits to be reaped from adding beans, peas and lentils to traditional crop rotations that typically includes wheat and barley. 

“This strategy can contribute significantly to the specific European Union Green Deal Farm to Fork objectives to reduce greenhouse gas emissions, chemical pesticide use and synthetic fertiliser use,” says lead author Marcela Porto Costa of Bangor University in Wales. 

When the researchers introduced legumes into the typical rotation in Scottish farms, Costa said that it “reduced external nitrogen requirements by almost half whilst maintaining the same output of food measured in terms of potential human nutrition.” 

This strategy can contribute significantly to the specific European Union Green Deal Farm to Fork objectives to reduce greenhouse gas emissions, chemical pesticide use and synthetic fertiliser use.

Marcela Porto Costa, Bangor University

This is because growing legume crops does not require fertilisers, and simply draws nitrogen from the air via natural bacteria. Fertiliser use has been on the rise, but they are depleting finite resources and causing huge amounts of greenhouse gas emissions – especially nitrous oxide, a gas that is 300-times more potent than carbon dioxide. 

Previous studies have warned that the increasing use of nitrogen fertilisers in food production and cultivating feed for animal agriculture has led to a 20% growth in pre-industrial levels of nitrous oxide, putting our climate targets at risk.

The European Green Deal’s Farm to Fork strategy therefore aims to cut synthetic fertiliser use by 20% by the end of the decade, as well as pesticide use by 50%. 

At the same time, legume crops enrich the soil with more nitrogen, reducing the need for the use of fertilisers for other non-legume crops that would typically rely on additional nitrogen.

“From a nutritional perspective, legumes are also one of the most nutrient-rich crops, providing protein, fiber, folate, iron, potassium, magnesium and vitamins,” wrote the researchers. 

The latest study is one of the most comprehensive to date because unlike previous research, it directly compares 10 different crop sequences using 16 different impact categories over the span of three to five years in a range of different European climates. 

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Legumes provide a healthier balance of carbohydrates, protein and fibre compared with cereal crops, and could improve the nutritional profile of the food we eat.

Dr. David Styles, University of Limerick

“Our innovative approach goes beyond simple food footprints by looking at the footprint of delivering a specific quantity of human, or livestock, nutrition from all crops produced within representative crop rotations,” explained co-author Dr. David Styles from the University of Limerick in Ireland. 

“Our results strengthen evidence on the positive role that healthy diet transitions could make to environmental sustainability,” Styles continued. “Legumes provide a healthier balance of carbohydrates, protein and fibre compared with cereal crops, and could improve the nutritional profile of the food we eat.”

Similar recommendations have been made by the non-profit European Alliance for Plant-based Foods (EAPF) with the view to boost the sustainability of European agriculture. Members of the organisation have called on European leaders to place plant-based foods, such as legume crops and plant-based alternative products, at the centre of its plans to reduce food production emissions while promoting better health. 

The group also asked lawmakers to provide more choices for consumers to diversify their diets with environmentally-friendly and healthy foods, increase investment into novel alternative proteins, and to encourage farmers to transition to climate-friendly crop production. 

“Plant-based foods have a central role to play,” said the EAPF, at the time of the organisation’s launch in September last year. “They concretely contribute to reaching the environmental goals of the EU Green Deal and the agri-food transition set forth in the Farm to Fork Strategy along the whole food value chain.”

Lead image courtesy of iStock.