Why is grass-fed beef healthier than grain-fed beef?

Beef: On average, grass-fed beef tends to have slightly lower levels of MUFA and slightly higher levels of PUFA than grain-fed, but these differences are at most five percentage points, depending on the breed of cattle and the study in question. Another reason grass-fed meat surpasses grain-fed is that it contains considerably more antioxidants, vitamins, and minerals. Carotenoids, such as beta-carotene