Although it may come as a shock and surprise to most Christians, Christ did not declare all foods clean.

Some may point to various translations of Mark 7:19 and claim that He did.

But before coming to any conclusion, we should consider these points:

Yeshua explicitly tells us that we should not think that He abolished or removed "the smallest letter or stroke" of the Law (Matthew 5:17-19). If He "declared all foods clean," then He would have nullified the instruction of two entire chapters of the Law (Leviticus 11 and Deuteronomy 14).
Peter never thought that Yeshua declared all foods clean. On the contrary, he rejected unclean food even after Messiah's death, burial, and resurrection (Acts 10:10-18).
His opponents never thought that Yeshua declared all foods clean. If they had, they would have had ample reason to kill Him, according to Deuteronomy 13:4-5. They would not have had to make up false charges against Him.

Scripture tells us that the laws G-d gave regarding food were not for health reasons but for the purpose of holiness (Leviticus 11:44-47).

For a detailed examination of this issue, see my article on What Scripture Says About Food.

Jesus Did Not Declare All Foods Clean