Evidence
Every important statement on this site is a claim with a record: what it says, how strong the evidence is and why, what its limits are, and which sources support or challenge it.
How we rate evidenceYes. Animal foods produce most of food's emissions, and beef and lamb produce the most per gram of protein. Eating less of them lowers a diet's footprint substantially.
Beef is in a different league from plant proteins on emissions. Chicken and eggs sit in between.
Most farmland feeds animals, not people directly. That land delivers a relatively small share of our food.
Soy grown for tofu and soy milk is a small slice of the total. Most soy feeds chickens, pigs and cows.
Better, in some ways, but not low-impact. Soil carbon gains are real, limited, and temporary.
About ten land animals per person per year, most of them chickens. Fish are not counted individually, but likely add far more.
The animals we farm can feel pain. For fish the evidence is strong; for crabs and lobsters it is now considered substantial.
People eating plant-based diets have fewer heart attacks on average. Trials show these diets lower cholesterol, which supports a causal link.
It can be, if it is built on whole foods and covers a few nutrients. 'Vegan' on its own is not a health claim.
Yes. This is the one nutrient a vegan diet cannot supply on its own. A cheap supplement solves it.
Yes for most people. Beans, lentils, tofu, grains and nuts add up. Athletes and older adults should plan a little more deliberately.
Each record summarises what a source found, its limitations, funding, and which claims it supports or complicates, with a link to the original. Why we do this.
Joseph Poore, Thomas Nemecek (2018). Science.
Xiaoming Xu, Prateek Sharma, Shijie Shu et al. (2021). Nature Food.
Food and Agriculture Organization of the United Nations (2024). FAOSTAT database.
Hannah Ritchie (2021). Our World in Data.
Jonathan Birch, Charlotte Burn, Alexandra Schnell et al. (2021). Report commissioned by the UK Government (Defra).
Lynne Sneddon, Robert Elwood, Shelley Adamo et al. (2014). Animal Behaviour.
Monica Dinu, Rosanna Abbate, Gian Franco Gensini et al. (2017). Critical Reviews in Food Science and Nutrition.
Fenglei Wang, Jusheng Zheng, Bo Yang et al. (2015). Journal of the American Heart Association.
Roman Pawlak, Scott Parrott, Sudha Raj et al. (2013). Nutrition Reviews.
François Mariotti, Christopher Gardner (2019). Nutrients.
Daniela Cusack, et al. (2021). Global Change Biology.
Tara Garnett, Cécile Godde, et al. (2017). Food Climate Research Network, University of Oxford.
Samantha Kuzma, Marlena Chertock Bierkens, Liz Saccoccia et al. (2023). WRI Technical Note.
Various national LCA studies (2024). Compiled by The Balance of Health.
FAO Food Balance Sheets, UK National Diet and Nutrition Survey, USDA Economic Research Service et al. (2024). Compiled by The Balance of Health.
UK Eatwell Guide, Dietary Guidelines for Americans 2020–2025, German Nutrition Society (DGE) et al. (2024). Compiled by The Balance of Health.
World Animal Protection Animal Protection Index, EU Directive 98/58/EC and species directives, UK Animal Welfare Act 2006 et al. (2024). Compiled by The Balance of Health.
US Department of Agriculture, Agricultural Research Service (2024). USDA.