According to an article published by the European energy company Vattenfall on their website referring to the German Environment Agency, “A vegan diet produces around 40 percent less CO₂ emissions […] compared to someone who eats meat and dairy products.” The claim turns out to be mostly true.
The Vattenfall article mentions neither a date of publication nor a source for the information, which refers to the German Environment Agency (UBA). Vattenfall did not answer our research team’s request for information about their publication. Therefore, our team contacted the UBA to verify whether the figures did actually stem from them. Unfortunately, we were unable to obtain any further information about the context or the origin of this statement.
Germany: Is a mainly plant-based nutrition better for the environment?
In an official report from May 2024, the German Environment Agency states that for some years now, scientific analyses have shown that food systems can be a factor that influences whether the planetary limits can be met. In their report, they claim that it is scientifically undisputed that a key factor for the compatibility of diets with the planetary limits is the quantity of animal-based foods.
According to this report, it has been calculated that in Germany, around two thirds of food-related greenhouse gas emissions, around two thirds to three quarters of the land required for food and three quarters of the food-related biodiversity footprint can be attributed to the proportion of animal-based foods.
In 2024, the German Nutrition Society (DGE) made changes in their dietary recommendations for citizens in Germany. What is new is that – in addition to focusing on health – the DGE also takes aspects such as sustainability and environmental impact into account. The organisation states: “A healthy and ecologically sustainable diet consists of more than three quarters plant-based foods and just under one quarter animal-based foods.”
In the same year, the DGE also updated their position statement on a vegan diet.
This statement evaluates new data on a vegan diet’s health effect. It further sheds light on the environmental dimension of this diet, among other aspects, looking into the reduction effect of a vegan diet in terms of greenhouse gas emissions compared to a diet with a high meat consumption. The DGE does so by carrying out an umbrella review, which allows the society to summarise “the evidence on a specific research question from several previously published systematic reviews into a clearly structured study”. A systematic review in order to identify and summarise studies relevant for the society’s position statement was added as well.
The different studies the update of the DGE position statement on a vegan diet takes into account vary with regard to the size of the reduction potential of greenhouse gas emissions. In this respect, the studies indicate that compared to omnivorous diets, a vegan diet has the potential to reduce 69 to 81 percent of greenhouse gas emissions. Therefore, a vegan diet “can be expected to have a lower environmental impact than current omnivorous diets”. According to the DGE, generally speaking, one could say that “the lower the proportion of animal products in the diet, the lower the environmental impact”.
Limitations the research faces
Calculating the environmental impact of different diets comes with certain challenges:
The climate impact of greenhouse gases such as methane (CH₄) and nitrous oxide (N₂O) often needs to be converted into carbon dioxide (CO₂) equivalents. This makes it possible to specify total national greenhouse gas emissions on which, for example, reduction targets and obligations are based and which make the data from different countries comparable.
However, research often focuses on greenhouse gas emissions as a bigger concept, rather than specifically examining CO₂ emissions.
Furthermore, when looking at environmental effects, it is important to take into account that such data can only be deduced from model calculations.
The DGE stresses that it’s important to cautiously interpret quantitative data on reduction potentials, as they often work with so-called life cycle assessments. Those are based on “relatively rigid assumptions regarding product and region-specific emission parameters or land-use coefficients”. Life cycle assessments often multiply the consumption quantities by the characterisation factors mentioned in the research.
Such studies can “reflect the environmental impacts of specific foods”, but they can only map “linear relationships”, often without “dynamic adjustments in the agricultural and food system”.
In general, “model simulations can […] only describe food groups and not individual foods”.
Additionally, research on reduction potentials does not always take aspects into account that would be relevant “if large sections of the population were to switch to a vegan diet”.Furthermore, there is an increasing relevance for research to consider innovative foods that are consumed as alternatives to animal-based products.
Germany: a scientific outlook on the effects of a potential mainly plant-based diet
According to an analysis of the environmental effects and policy implications of dietary change in Germany published by the German Environment Agency (UBA) in 2023, there’s a large potential for diet-related reductions in environmental pollution. The report analysing and projecting the potential environmental effects of dietary change in Germany found that in 2050, the production of animal products is estimated to generate the majority of food-related greenhouse gas emissions (60-63 percent of total agricultural emissions in 2010; 59-61 percent estimated for 2050). The UBA’s publication associates changes from current diets to predominantly plant-based dietary patterns with reduced food-related greenhouse gas emissions of Germany of 40-52 million (mega) tonnes of carbon dioxide equivalents. This represents a reduction of 63-81 percent in overall food-related greenhouse gas emissions.
Global comparisons
A 2014 UK-based study published in “Climatic Change” found out that individuals following a vegan diet emit on average 1,000.1 kilograms less CO₂ per year than meat eaters, which corresponds to a 48.7 percent reduction. Although the study is not the most recent, it still serves as a valuable point of comparison due to its detailed methodology and large sample size.
In the US, research published in 2023 in “The American Journal of Clinical Nutrition” showed that vegans emit 504 kilograms of CO₂ per year, while omnivores emit 1,629 kilograms, resulting in a difference of 1,125 kilograms and a reduction of 69.1 percent.
Our team didn’t find authoritative studies claiming that a vegan diet doesn’t contribute to carbon emission reduction, so there seems to be a scientific consensus supporting the essence of the claim published in Vattenfall’s article.
Explanation for different amounts of carbon footprints
One key reason for the significantly higher carbon footprint of a meat-based diet lies in the resource-intensive production of animal-based foods. According to the German Environment Agency, livestock farming not only directly produces large amounts of greenhouse gases – primarily methane (CH₄) and nitrous oxide (N₂O) – but also significantly contributes to other serious environmental problems. For example, in Germany, around 60 percent of agricultural land is used to grow animal feed. This land could instead be used to cultivate food for direct human consumption, which would be more efficient.
Conclusion
In short, the statement “a vegan diet produces around 40 percent less CO₂ emissions […] compared to someone who eats meat and dairy products” is mostly true. The general statement that a vegan diet is better for the environment and produces less carbon dioxide emissions is correct. However, research shows that the results of these calculations vary. Specific numbers must therefore be treated with caution.
RESEARCH | ARTICLE © Alice Kärcher and Kim Romagnoli | Hochschule der Medien Stuttgart, Germany | Lea Manger and Annalena Meyer | Jade Hochschule Wilhelmshaven, Germany | Kosmos Khoroshavin | Thomas More University of Applied Sciences, Belgium | Jochem Verhoeven | Utrecht University of Applied Sciences, the Netherlands
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