Recent studies have clearly shown health benefits of grassfed beef over grainfed. The optimum ratio of omega-6:omega-3 is 1:1 to 4:1; grassfed is 1.53:1 and grainfed is 7.65:1. Favorable association with cardiac and cancer issues has been shown. Grass feed beef has more conjugated linoleic acid (CLA) than grain fed beef. CLA is a powerful polyunsaturated fatty acid that has been shown to help fight cancer, help with weight loss and build muscle.
A recent study has shown 18 % of conventional beef has measurable multi-drug resistant bacteria compared to only 6% for grassfed. As we use no antibiotics in our grassfed cattle, and never have since we started the herd back in 1974, we would imagine we should approach zero in such studies.