If you read on in John's Gospels, Jesus then says that He is the Bread of Life. I would interpret this as Jesus is able to give us all we need (We pray - Give us this day our daily bread). God fed the Israelites in the wilderness and provided them with manna but Jesus provides more. He does not just feed us but He provides in abundance as there were 12 baskets filled with leftovers! For food to do any good it needs to be digested. Jesus therefore needs to be taken in also - hence the references to what we now know as the Eucharist. (John's gospel does not mention the Last Supper as the other gospels do but Jesus mentions about His body and blood after He says I AM the bread of life.) There is lots to unpick from this but my understanding would be that He provides all we need in abundance if we believe and trust in Him (digest Him).