Different foods for different spiritual periods
Genesis 1:29
And God said, “See, I have given you every herb that yields seed which is on the face of all the earth, and every tree whose fruit yields seed; to you it shall be for food.
Genesis 9:3
Every moving thing that lives shall be food for you. I have given you all things, even as the green herbs. 4 But you shall not eat flesh with its life, that is, its blood.
Leviticus 11 (whole chapter)
From everything that moves restricted down to meat only good for sacrifices to God to show separated unto God.
Leviticus 20:25-26 (unclean foods equated to Gentiles)
25 You shall therefore distinguish between clean animals and unclean, between unclean birds and clean, and you shall not make yourselves abominable by beast or by bird, or by any kind of living thing that creeps on the ground, which I have separated from you as unclean. 26 And you shall be holy to Me, for I the Lord am holy, and have separated you from the peoples, that you should be Mine.
Acts 10:15 (with the spiritual cleansing of the Gentiles, all foods are now acceptable, going back to edict to Noah above, Genesis 9:3)
15 And a voice spoke to him again the second time, “What God has cleansed you must not call common.”
1 Corinthians 6:12-13 (no longer a sin to eat unclean meats, but not everything is healthy)
12 All things are lawful for me, but all things are not helpful. All things are lawful for me, but I will not be brought under the power of any. 13 Foods for the stomach and the stomach for foods, but God will destroy both it and them.
1 Timothy 4:1-5 (confirmation that food laws have gone back to the edict to Noah)
Now the Spirit expressly says that in latter times some will depart from the faith, giving heed to deceiving spirits and doctrines of demons, 2 speaking lies in hypocrisy, having their own conscience seared with a hot iron, 3 forbidding to marry, and commanding to abstain from food created to be received with thanksgiving by those who believe and know the truth. 4 For every creature of God is good, and nothing is to be refused if it is received with thanksgiving; 5 for it is sanctified by the word of God and prayer.
Conclusion, the original vegetarian diet is healthiest, but it is no longer a sin to eat meat of any kind if sanctified by the word of God and prayer.