Food is either the major, or one of the major drivers, of climate change, water stress, land use, biodiversity loss, soil erosion, deforestation and depletion of fish stocks. (11), (12), (13)
Environmental impact of the food system (11), (12), (13)
- accounts for 20-30% of global greenhouse gas emissions (GHGe)
- 80% of agricultural land is used for livestock
- major deforestation
- loss of biodiversity
- change in land use
- 70% of all human water use
- water pollution
A growing global population, which is estimated to reach over nine billion by 2050, and a trend towards a more ‘Western’ style of eating, will require more food to be produced, in particular meat and animal products. (14)
If we carry on as we are, experts suggest we will need to double food production by 2050 compared to 2010.(15) This will require 120% more water, 42% more cropland and a loss of 14% more forest, resulting in enough carbon dioxide to create 2 degrees of global warming, as well losing much of the world’s biodiversity. (16) Scientists say that if this 2oC limit is exceeded, we will see widespread extinction of animal and plant species, droughts, a rise in sea level and an increased risk of flooding in certain areas.
How do we meet the growing food demands, particularly animal foods, and prevent further damage to the planet? One answer is to eat a plant-based diet. Research has shown plant foods to be more environmentally friendly than animal foods as they require less land, water, energy and produce fewer GHGe. (11), (17), (18), (19), (20). Studies examining dietary patterns, differing in their animal food intake, have also found that those diets with fewer animal products, and based on plant foods, have a lower environmental impact. The greater the animal food restriction, the smaller the environmental footprint. (21)
One review of 60 studies found by switching to a sustainable dietary pattern, reductions as high as 70–80% of GHGe and land use, and 50% of water use could be achieved. Examples of these sustainable diets included vegetarian, vegan, pescatarian, replacing ruminant with monogastric meat (chicken, pork), balanced energy intake, following healthy guidelines, Mediterranean diet, New Nordic diet, etc. The largest environmental benefits were seen in those diets which most reduced the amount of animal-based foods.(13)
Issues to consider when defining a sustainable diet
Adapted from Food Climate Research Network (2)
The Food and Agriculture Organisation (FAO) said in 2010:
“Sustainable diets imply a change in dietary preferences to reduce overconsumption and a shift to nutritious diets with lower environmental footprints. They also mean a reduction of losses and waste throughout the food system. Ultimately, the aim of a successful transition to healthier and sustainable diets is for people and the ecosystem to be healthier” (1).
Greenhouse Gas Emissions:
The food system contributes to global greenhouse gas (GHG) emissions and accounts for approximately 30% of the European Union´s total GHGe (4, 5). Comparisons between different types of food show vegetables to be responsible for the lowest emissions, with the exception of air-freighted vegetables. Animal products are associated with higher emissions where ruminants (cattle and sheep) are responsible for the greatest proportion of GHGe (6).
A German study compared greenhouse gas emissions from four different diets:
- Typical current diet
- Diet consistent with recommendations
- Lacto-ovo vegetarian diet
- Vegan diets
The typical current diet gave rise to emissions of 2.1 tonnes of carbon dioxide equivalents per person per annum. The diet consistent with recommendations gave rise to 1.8 tonnes, The lacto-ovo vegetarian diet 1.6 tonnes and the vegan diet 1.0 tonne.
A major portion of the climate impact from Lacto-ovo vegetarian diets is caused by dairy products and the amount of milk in the diet is higher than in other diets (7).
Today numerous strategies and recommendations advise a reduction in both dairy and meat consumption in favour of plant foods (8). A healthy diet, consisting of two thirds plant food and one third animal products, is consistent with dietary recommendations and offers benefits for both health and the environment (9).
‘Climate Smart’ or environmentally friendly diet:
Adapted from ”Hur liten kan livsmedelskonsumtionens klimatpåverkan vara år 2050? Naturvårdsverket, Jordbruksverket, Livsmedelsverket”
Oatly’s Guide to Saving the Environment:
Step 1: Reduce food waste. Around one third of all food we buy is thrown away.
Step 2: Recommend choosing seasonal, local food and then eat according to dietary recommendations.
Step 3: Advise a change from dairy products to oat drinks. According to life cycle analyses (LCA), greenhouse gas emissions from oat drinks are just one third of those generated in the production of cows’ milk (10).
There are huge impacts on the environment from the diet we eat. Plant-based eating is beneficial for both health and planet.
9. Swedish National Food Administration. 2014. http://www.slv.se/sv/grupp1/Mat-och-naring/kostrad/Rad-om-vegetarisk-mat
10. Swedish National Food Administration. 2014. http://www.slv.se/sv/grupp1/Mat-och-naring/Maltider-i-vard-skola-omsorg/Skolmaltider/Vegetariska-skolmaltider/Vegankost-i-skolan/
11. Vermeulen SJ, Campbell BM, Ingram JIS. (2012) Climate change and food systems. Annu Rev Environ Resour; 37:195–222.
12. Garnett T. (2014) What is a Sustainable Healthy Diet? A Discussion Paper. Oxford: Food Climate Research Network.
13. Steinfeld H, et al. (2006) Livestock Long Shadow: Environmental Issues and Options. Rome: FAO
14. United Nations Department of Economic and Social Affairs Population Division (2015) World Population Prospects: The 2015 Revision, Key Findings and Advance Tables. Working Paper No. ESA/P/WP.241
15. Food and Agriculture Organization (2010) International Scientific Symposium. Biodiversity and Sustainable Diets - United against Hunger
16. Bajzelj B, et al. (2014). Importance of Food-Demand Management for Climate Mitigation. Nature Climate Change; 4: 924-29
17. Ranganathan, J. et al. (2016). Shifting Diets for a Sustainable Food Future. Working Paper, Instalment 11 of Creating a Sustainable Food Future. Washington, DC: World Resources Institute.
18. Audsley et al. (2009) How low can we go? an assessment of greenhouse gas emissions from the UK food system and the scope to reduce them by 2050. Food Climate Research Network & WWF, London, UK
19. Carlsson-Kanyama A, Gonzalez A (2009) Potential contributions of food consumption patterns to climate change. Am J Clin Nutr; 89: 1S–6S
20. Committee on Climate Change (2010) The fourth carbon budget. Reducing emissions through the 2020s. Committee on Climate Change, London, UK
21. Aleksandrowicz L, et al. (2016) The Impacts of Dietary Change on Greenhouse Gas Emissions, Land Use, Water Use, and Health: A Systematic Review. PLoS ONE; 11(11): e0165797
22. Food and Agriculture Organization (2010) International Scientific Symposium. Biodiversity and Sustainable Diets - United against Hunger