Cows graze on a grass field at a farm in Schaghticoke, N.Y. The grass-fed movement is based on the idea of regenerative agriculture. John Greim/LightRocket via Getty Images hide caption toggle caption John Greim/LightRocket via Getty Images The Salt Is Grass-Fed Beef Really Better For The Planet? Here's The Science August 13, 2019 There are many elements to consider: climate, animal welfare, greenhouse gas emissions, land use. And with so many factors at play, sometimes the answer gets complicated.