What Is a Sustainable Diet?
Sustainable diets take into account the environmental impact of the meal from different perspectives, including land use, energy or water footprint. This means that everything from vegan to vegetarian or flexitarian menus can constitute a sustainable plant-based diet.
Why Are Sustainable Diets Important?
Sustainability is one of humanity’s most important goals for the 21st century. Here are the headlines:
The Human Population is Expanding Fast
- By 2050, the earth will have 9.1 billion people–almost 20 percent more than the 7.6 billion people who live here today.1
- About 6.4 billion people will be urban compared to 3.7 billion today.
- City dwellers have larger incomes and eat more meat on average.
- Our current food system uses over 30% of all ice-free land, 70% of all fresh water and 20% of all energy.2
- To feed this larger, wealthier, urban population, food production needs to increase by 70% through 2050.
- There are currently 55 billion livestock consuming food grown on nearly ¾ of the arable land.
- There is simply not enough land to feed 9 billion the current diet.
Shifting Toward a More Plant-Based Diet
- Beef protein requires about 100 times more water than the same amount of plant protein.3
- 1 acre of farmland is enough to produce 9 kg of protein from beef and 161 kg of protein from soy.
- Soy contains 35-40% protein and includes all essential amino acids. However, 75% of soy is fed to livestock.2
Pollution from Plants
Even as we strive for a more sustainable plant-based diet, crop production still requires a nitrogen source. This is most commonly provided through nitrogen fertilizer, which requires tremendous energy, and as a pollutant, is considered among the top three threats to global biodiversity. More sustainable farming methods like crop rotation will need to be explored.4
If you want to find out more about plant-based diets, our quick guide will help you understand what’s the difference between the various types.
- How to Feed the World in 2050. www.FAO.org.
- The Hidden World of Soy. World Wildlife Foundation.
- Sustainability of meat-based and plant-based diets and the environment. Pimentel and Pimentel 2003
- Aiking, Harry. Future Protein Supply. Institute for Environmental Studies, 2011.
8. Kaldy, M.S. Econ Bot 1972. 26: 142. https://doi.org/10.1007/BF02860775