What the Latest Research on an Environmentally Sustainable and Nutritious Diet Means for Us
“Food is the single strongest lever to optimize human health and environmental sustainability on earth” (EAT-Lancet commission). The 2019 EAT-Lancet report goes on to explain how to change our food system to ensure we meet the UN’s Sustainable Development Goals and the Paris climate change agreement. Current agricultural practices have been noted to degrade land and water ecosystems, deplete water resources and significantly contribute to climate change. The UN Food and Agriculture Organization (FAO) says food yields need to increase by about 60% from 2006 to feed the 9 to 10 billion people present in 2050. To meet this challenge while not degrading our natural environment the EAT-Lancet report says a move towards a nutritious plant-based diet is required. Here is why.
Livestock Agriculture’s Contribution to Land Use Change – Why a Plant-Based Diet
A 2018 Science journal article stated that meat, aquaculture, eggs, and dairy use approximately 83% of the world’s farmland despite providing only 37% of our protein and 18% of our calories. A significant amount of this land is used to produce feed for farm animals with the EAT-Lancet report indicating that two thirds of all soybeans, maize and barley grown are used as farm animal food. Wealthy countries typically have significantly higher per capita meat consumption resulting in land use which could otherwise be used to feed poorer parts of the world and a growing global middle-class.
Livestock Agriculture’s Contribution to Climate Change – Why a Plant-Based Diet
Livestock agriculture is a significant contributor to climate change. Between 15% (a 2013 FAO report) and 51% (a 2009 World Watch Institute report) of total emissions have been attributed to livestock with the variation being due to differing data and methods. Reasons for livestock emissions include methane production from livestock digestion, fertilizer production for feed crops and loss of CO2 absorbing trees cleared for livestock. As an example consider research showing that production of legumes (beans, peas, etc.) releases one-fortieth the amount of climate change emissions as beef despite delivering more calories and protein pound for pound. The EAT-Lancet report states that a plant-based diet has the potential to reduce agricultural emissions by up to 80%.
Livestock Agriculture’s Contribution to Fresh Water Use – Why a Plant-Based Diet
The world is running out of freshwater. Researchers have predicted future conflicts due to depletion of this precious resource. Agriculture is the world’s largest consumer of freshwater responsible for about 70% of freshwater withdrawals. A study published by UNESCO-IHE Institute for Water Education studied agriculture water consumption and found the following when comparing water use for producing vegetables versus bovine meat:
| Litres of water | Litres of water for a kilocalorie | Litres of water for a gram of protein | |
| Vegetables (1 kg) | 322 | 1.34 | 26 |
| Bovine Meat (1kg) | 15,415 | 10.19 | 112 |
With one third of agriculture freshwater consumption being due to animal agriculture a shift to a plant-based diet can help free freshwater resources to feed an increasing global population.
Conclusion
Adopting a primarily plant-based diet with less meat will reduce your environmental footprint and if done prudently can also be a nutritious choice. As citizens, you can also support regulations and taxation to encourage plant-based foods. Will you be part of this shift towards sustainable agriculture?
