All Butter comes from cows that is just really milk fat but grass fed butter which is butter that comes from the milk fat of grass fed cows in healthier than regular butter that is made from cows milk fat that are grain fed.
Grass Fed Butter which is butter made from milk fat from grass fed cows contains 5 times more CLA than regular butter and also is higher in Omega-3 fatty acids and vitamin K2 than regular butter from grain fed cows.
Still any butter is not good for your health if you eat too much of it but the grass fed butter is the healthier choice when it comes to choosing butter.