ABSTRACT
Since at least 1989, the United States (U.S.) livestock industry knew of its role in global warming (Gibbs et al. 1989), and a newly uncovered industry document makes clear that the industry planned to obstruct efforts to shift U.S. diets to reduce emissions (NCA 1989). These internal industry plans add to publicly available evidence that shows that the U.S. livestock industry has, from 1989 to the present, worked to obstruct efforts to encourage meat reduction for the sake of climate change, including recent, modest efforts such as Meatless Mondays, as well as a more ambitious campaign in the 1990s to cut U.S. beef consumption in half (Loy and Jacquet 2025). We recognize that a reduction of per capita beef consumption by 50% would have likely faced obstacles beyond those directly imposed by industry, but also see value in exploring what halving U.S. consumption of beef, the most greenhouse gas (GHG) intensive food (Poore and Nemecek 2018; Pierrehumbert and Eshel 2015), might have meant for U.S. GHG emissions reductions. Using a model that reduced annual per capita beef and veal consumption by 50% over 32 years spanning 1992-2023 (and substituted in other foods, including non-beef animal-based products), estimated cumulative averted emissions could have been somewhere between 4 and 13 gigatonne (Gt) CO2eq (estimated U.S. emissions in 2022 were 6.2 Gt CO2). The low-tech and immediately available option of halving U.S. beef and veal consumption, resulting in a savings of 125-410 megatonnes (Mt) CO2eq per year over the 32-year period, could have been 24-80 times more effective in reducing GHG emissions in a single year than what was achieved cumulatively by reducing methane emissions (mainly in the oil and gas industries) over a similar timespan (1990-2022).