Nationwide shift to grass-fed beef requires larger cattle population
Level 5 - mechanism / opinion, no new human data
Level 5 by design analogy (computational demographic simulation model).
OpenAlex W2884990483 · doi:10.1088/1748-9326/aad401
What was done
The authors modeled a nationwide transition in the United States from grain-finishing feedlot systems to exclusively pasture- and forage-finishing systems using present-day beef cattle demographic parameters. The model evaluated the cattle herd size and land resources required to match current US beef production volume under pasture-only and cropland-forage scenarios.
What was found
Maintaining current beef output purely on grass requires increasing the national cattle herd by 30%, from 77 to 100 million head. Existing US pastureland grass can support only 27% of current beef supply (27 million cattle), which is 30% below prior estimates. Adding cropland-raised forage supports an additional 34 million cattle, reaching up to 61% of current beef supply.
Why it matters
This analysis shows that transitioning entirely to grass-fed beef cannot meet present domestic demand without expanding cattle populations, increasing land-use competition, or raising methane emissions, indicating that reducing beef consumption is necessary to lower environmental impacts.
Limits
The findings derive from a demographic simulation model rather than empirical field measurements. The abstract does not provide exact data sources, confidence bounds, economic elasticity estimates, or direct measurements of soil carbon fluxes across varying grazing practices.
Cited by
- supports Grass-fed cattle require more land and water and live longer before slaughter compared to conventionally raised feedlot cattle.