Grass Finished has no legal meaning and is a marketing claim.
Naturally Raised is an USDA term with legal standing. This includes that the animal has never been fed animal byproducts, growth hormones, antibiotics, but it can be fed grains or grass and could be raised in a CAFO.
Natural applies only to a finished product – it must contain no artificial ingredients or added color and is minimally processed, the product has not been fundamentally altered. It has nothing to do with how the animal was raised or what it was fed.
Organic requires USDA certification, raised without antibiotics or synthetic hormones, on feed that is vegetarian, pesticide- and herbicide-free, and contains no GMOs. It does not mean that the animal has been grass fed. Therefore, the animal can be fed grass, organic grains, and grain by products during periods of confinement.
I would highly encourage purchasing as much of your red meat from local farms; get to know the farmer, ask many questions, and even ask to visit the farm. There are many wonderful farms that are caring for the land and the animals they raise in a sustainable and healthy way.
I would highly suggest that if you choose to eat pork, find a farmer that you can get to know. Pigs should be pasture raised but that term can be vague. This is why it is important to know your farmer and the standards they practice.
I hope this information has been helpful for you, and you are able to make quality decisions when purchasing your red meat.
Be blessed and be a blessing,
Heather