Daniel 1:10-13

yet he said to Daniel, “I fear my lord the king, who assigned your food and drink. What if he sees your faces looking thinner than the other young men your age? You would endanger my life with the king.” So Daniel said to the guard whom the chief eunuch had assigned to Daniel, Hananiah, Mishael, and Azariah, “Please test your servants for ten days. Let us be given vegetables to eat and water to drink. Then examine our appearance and the appearance of the young men who are eating the king’s food, and deal with your servants based on what you see.”