Beef, chicken, or plants: what your food does to the climate
Food is about a quarter of global greenhouse gas emissions, and within food the differences between choices are enormous. The clearest dataset we have — Poore & Nemecek’s 2018 study in Science, covering ~38,000 farms — lets us put rough numbers on a plate.
Kilograms of CO₂e per kilogram of food
| Food | kg CO₂e per kg |
|---|---|
| Beef (beef herd) | ~60 |
| Lamb & mutton | ~24 |
| Cheese | ~21 |
| Pork | ~7 |
| Chicken | ~6 |
| Tofu | ~3 |
| Beans / lentils | ~1–2 |
| Most vegetables | ~0.4–2 |
Beef sits roughly ten times higher than chicken and twenty to fifty times higher than most plants. Lamb and cheese are close behind beef. This is the single biggest lever in the food category, and it’s not subtle.
Why “eat local” matters less than people think
Transport is a surprisingly small slice of most foods’ footprint — usually under 10%. For beef, how the animal was raised dwarfs how far the meat travelled. A plant flown in from another continent is still, in most cases, lower-carbon than local beef. “What you eat” beats “where it came from” by a wide margin, with the narrow exception of foods air-freighted because they’re highly perishable.
What a realistic shift looks like
You don’t need to go fully vegan to move the number. Per Our World in Data, the gap between a high-meat diet and a vegetarian or vegan one is on the order of a tonne of CO₂e per year for one person. Even cutting beef and lamb to occasional rather than routine captures most of the available reduction, because they’re such outliers.
- Biggest win: less beef, lamb, and cheese.
- Solid win: swap some red meat for chicken, fish, or legumes — even your coffee follows the same rule (it’s the dairy).
- Marginal: worrying about food miles, packaging, or “organic” labels — real, but small next to the above.
The honest framing
Diet is personal, and this isn’t a sermon. But if you want the food part of your footprint to fall, the data points almost entirely at ruminant animals — beef, lamb, dairy. CO2Mate logs meals against published emission factors so you can see your own food number move as your choices do, instead of guessing.
Sources: Poore & Nemecek (2018), Science, via Our World in Data, “Environmental impacts of food production”; Our World in Data, “You want to reduce the carbon footprint of your food?”