Frequently Asked Question
Environment & Climate“Plant-based is more efficient (thermodynamics / trophic levels)”
Last reviewed: January 9, 2026
Summary
Converting crops into animal products loses energy and protein at each trophic step, so producing animal calories/protein generally requires more land and inputs than producing plant foods directly. Empirical analyses show that reallocating crops currently fed to animals could feed many more people.
Supported by 3 cited sources
Evidence Summary
- Opportunity-cost studies quantify large calorie/protein losses from feeding edible crops to livestock.
- Land and resource use per unit food is typically higher for animal products. Evidence quality: High Limitations / nuance: Some grazing uses non-arable land; but overall land-use and opportunity-cost results remain substantial. Bottom line: Efficiency is not a “debate”; it’s basic ecology + measured food-system data.
Supporting Evidence
This is basic ecological thermodynamics: energy is lost at each transfer between trophic levels.
Sources & Evidence
3 sources cited across 2 claims
1
Feed-to-meat conversion loses energy at each trophic level
Systematic ReviewThe carbon opportunity cost of animal-sourced food production on land. — Hayek MN, et al. (2021)
Opportunity cost of animal-based diets exceeds all food losses. — Shepon A, et al. (2018)
Redefining agricultural yields… — Cassidy ES, et al. (2013)
2
Feed crops could feed more people if eaten directly
ModelingThe carbon opportunity cost of animal-sourced food production on land. — Hayek MN, et al. (2021)
Opportunity cost of animal-based diets exceeds all food losses. — Shepon A, et al. (2018)
Redefining agricultural yields… — Cassidy ES, et al. (2013)