Withdrawing GET from U.S. beef production reduced productivity (growth rate and slaughter weight) and increased the population size required to produce 454 × 106 kg beef by 385 × 103 animals. Feedstuff and land use were increased by 2,830 × 103 t and 265 × 103 ha, respectively, by GET withdrawal, with 20,139 × 106 more liters of water being required to maintain beef production. Manure output increased by 1,799 × 103 t as a result of GET withdrawal, with an increase in carbon emissions of 714,515 t/454 × 106 kg beef