“Grass fed” and “grass finished” are different claims on a US beef label. Grass-fed cattle eat only forage after weaning and are never confined to a feedlot. Grass-finished cattle can be fed grain before the end. A 2010 review of the research found that a grass-based diet changes the fat in the meat, mostly in its omega-3 and CLA content. Here is what each label word means, and what the studies found.
What “grass fed” means on a label
The USDA’s Food Safety and Inspection Service treats “Grass Fed,” “Grassfed,” “Grass-Fed” and “100% Grass-Fed” as one claim. It applies to beef from cattle that were “only (100%) fed forage (e.g., grass) after being weaned from their mother’s milk”, which “means such animals are never confined to a feedlot.”
The animals “cannot be fed grain or grain by-products and must have continuous access to pasture during the growing season until slaughter.” Hay, haylage and silage count as forage. Routine mineral and vitamin supplements are allowed.
What “grass finished” means
The same guideline says “Grass Finished” is not the same claim as “Grass Fed”. A grass-finished animal can be fed grain, and FSIS gives “Grain Fed, Grass Finished” as a label that would be truthful for it.
When an animal’s diet after weaning was not 100 percent forage, the label “must accurately reflect the circumstances of raising”. FSIS’s own example is “Made from cattle fed grass and corn”.
So if you want beef from cattle that never ate grain, the words to look for are “grass fed” or “100% grass-fed”, not “grass finished”. FSIS notes that its guideline does not carry the force of law; it describes the documents FSIS expects before it approves a label claim.
What changes in the meat
In 2010, Cynthia Daley and colleagues reviewed three decades of research comparing grass-fed and grain-fed beef. They found that grass-based diets “can significantly improve the fatty acid (FA) composition and antioxidant content of beef, albeit with variable impacts on overall palatability.”
- More omega-3 fatty acids and more conjugated linoleic acid (CLA), measured per gram of fat.
- The same total saturated fat, but more of it is stearic acid and less is myristic and palmitic acid.
- Higher levels of the precursors for vitamins A and E.
- Less fat overall.
The review adds a fair caveat: people who eat grain-fed beef “may achieve similar intakes of both n-3 and CLA through the consumption of higher fat grain-fed portions.” Leaner grass-fed meat carries more of these per gram of fat, and fattier grain-fed cuts carry more fat.
What changes in the kitchen
The same review notes that grass-fed beef has “a distinct grass flavor and unique cooking qualities”, and that its fat “may have a yellowish appearance from the elevated carotenoid content”. With less fat, a grass-fed steak cooks differently from a grain-fed one, and the yellow tint in the fat is normal.
Sources
- USDA Food Safety and Inspection Service. FSIS Guideline on Substantiating Animal-Raising or Environment-Related Labeling Claims. August 2024. FSIS-GD-2024-0006. fsis.usda.gov
- Daley CA, Abbott A, Doyle PS, Nader GA, Larson S. A review of fatty acid profiles and antioxidant content in grass-fed and grain-fed beef. Nutrition Journal. 2010;9:10. PMC2846864
One Response
Thank you for the article! Very useful knowledge to have for sure!
– Lina