Food is conducive to gratitude. Perhaps gratitude is, in its own right, a type of nourishment. This idea goes back at least as far as the Bible, where eating and giving thanks are often closely linked. When food is paired with the word blessing, the implication is often gratitude. The Greek verb translated "to bless" in the New Testament can easily be rendered "to celebrate with thanks."
On countless occasions, Jesus blessed—or gave thanks for—everything from his food to his friends to his enemies. Most would agree that he did this without any expectation of reciprocity from God, but that it was simply his nature to be thankful. He gave thanks even when those around him might have wondered whether there was anything to be grateful for. And he did, on a couple of occasions, use food almost as a type of instructional tool from which his followers could learn how to be grateful in as sincere a way as he was.
This results of his giving thanks in particular situations tended to turn circumstances upside down. There's the feeding of the five thousand, when a large crowd approaches Jesus at the time of the Passover feast. See John 6:4–13 . Jesus and his disciples can't turn their backs on them. But all they have is five loaves of barley bread and a couple of fish. Jesus, apparently unfazed, has everyone sit down to prepare to be fed. The Gospel records that Jesus does only one thing before distributing the food. He gives thanks.
