Daniel 1:11-16

But Daniel appealed to a steward who had been assigned by the head of the palace staff to be in charge of Daniel, Hananiah, Mishael, and Azariah: “Try us out for ten days on a simple diet of vegetables and water. Then compare us with the young men who eat from the royal menu. Make your decision on the basis of what you see.” The steward agreed to do it and fed them vegetables and water for ten days. At the end of the ten days they looked better and more robust than all the others who had been eating from the royal menu. So the steward continued to exempt them from the royal menu of food and drink and served them only vegetables.