In the most comprehensive analysis to date on the subject, a new study by Oxford University has shown that eating a vegan diet massively reduces the damage to the environment caused by food production compared with all the other available diets. It concludes that vegan diets result in 75% less climate-heating emissions, water pollution and land use than diets in which more than 100g of meat a day was eaten. Vegan diets also cut the destruction of wildlife by 66% and water use by 54%.
Interestingly, the study, titled “Vegans, vegetarians, fish-eaters and meat-eaters in the UK show discrepant environmental impacts”, also shows that low-meat diets (less than 50g a day) had half the impact of high-meat diets on greenhouse gas emissions, water pollution, and land use, but the differences between low-meat, pescatarian, and vegetarian diets were relatively small. The biggest difference seen in the study was for emissions of methane, a greenhouse gas produced by ruminants such as cows and sheeps, which were 93% lower for vegan diets compared with high-meat diets (and it would be even lower for ethical vegans, as the avoidance of wearing wool would contribute to lower their carbon footprint).
Previous studies have used model diets and average values for the impact of each food type, but this study, published in the journal Nature Food, is the first one where real diets of 55,000 people in the UK, as well as data from 38,000 farms in 119 countries, were analysed.
Prof Peter Scarborough, who led the research at Oxford University, said to the Guardian: “Our dietary choices have a big impact on the planet. Cutting down the amount of meat and dairy in your diet can make a big difference to your dietary footprint.”
Prof Richard Tiffin at the University of Reading said, “This study represents the most comprehensive attempt to link food consumption data to the data on the environmental impacts of food production. Encouraging high-meat-eaters to reduce meat consumption and encouraging vegetarians to become vegans should result in lower emissions. However, it’s hard to justify changes to the diets of moderate omnivores on the basis of these results, other than to switch to a completely vegan diet.” This goes to show that choosing reducetarian, vegetarian, flexitarian or pescatarian diets is not enough and veganism is the only logical ethical choice.