There is something to that, as you have said. However, we live in the new dispensation, right?
Acts Chapter 10
9 On the morrow, as they went on their journey, and drew nigh unto the city, Peter went up upon the housetop to pray about the sixth hour:
10 And he became very hungry, and would have eaten: but while they made ready, he fell into a trance,
11 And saw heaven opened, and a certain vessel descending unto him, as it had been a great sheet knit at the four corners, and let down to the earth:
12 Wherein were all manner of fourfooted beasts of the earth, and wild beasts, and creeping things, and fowls of the air.
13 And there came a voice to him, Rise, Peter; kill, and eat.
14 But Peter said, Not so, Lord; for I have never eaten any thing that is common or unclean.
15 And the voice spake unto him again the second time, What God hath cleansed, that call not thou common.
16 This was done thrice: and the vessel was received up again into heaven.
For personal health reasons, there were reasons I could not eat certain meats. But since the Lord has provided some healing for me, I have been able to eat them again and have enjoyed them, grass-fed, free range only, ect. . ., with my family and the Lord has blessed it for our bodies.
I think what I am trying to say here is that you must follow your convictions from the Holy Spirit on your diet. Some things, obviously, are not good to eat, like grain-fed beef can be toxic because cattle are made to eat grass, as an example. But, we live at liberty in Christ, and as long as we do not sin by going against our convictions or being gluttons, we are at liberty to eat.