Claim
Reducing meat and dairy consumption, especially beef and lamb, is one of the largest ways an individual's diet can reduce greenhouse gas emissions.
Yes. 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.
- Last reviewed
- Reviewer
- Editorial placeholder
- Status
- sample
Sample data. The figures and sources on this page are demonstration records showing how evidence will be presented. They are approximate and have not yet been through our review process. Read about how we will verify evidence.
Why this rating: Multiple independent global analyses using different methods reach the same ranking of foods, and the size of the gap is large enough that methodological choices do not change the conclusion.
Supported by multiple systematic reviews or large, consistent studies using different methods, with few plausible alternative explanations.
Explanation
Food is responsible for roughly a quarter of global greenhouse gas emissions. Within that, animal-based foods account for more than half, even though they supply a minority of calories.
The difference comes from biology and land. Cattle and sheep digest grass by fermentation, which releases methane. Raising animals also needs land for grazing and feed, and clearing that land releases stored carbon.
Limitations
- Emissions per food are averages; a low-impact beef producer and a high-impact one can differ several-fold.
- Individual diet change matters most when it is widespread; a single person's change is small in absolute terms.
Methodology
- Life-cycle assessments trace emissions from land clearing through farming, processing, transport and retail.
- Results are expressed in CO₂-equivalents so that methane and nitrous oxide can be compared with carbon dioxide.
Sources for this claim
Each source links to our record of what it found, its limitations and what we used it for, with a link to the original.
- 1Reducing food's environmental impacts through producers and consumers
Joseph Poore, Thomas Nemecek (2018). Science.
- 2Global greenhouse gas emissions from animal-based foods are twice those of plant-based foods
Xiaoming Xu, Prateek Sharma, Shijie Shu et al. (2021). Nature Food.