In the Bible (Book of Daniel), Daniel has the opportunity to eat the finest meats and wines in the world, but chooses "pulse" and water. Some say pulse is like spinach, others say it was a legume. You gotta love the source!
Daniel purposed in his heart that he would not defile himself by eating the food and drinking the wine of the royal court. He asked Ashpenaz to help him so he would not be defiled, and God made Ashpenaz sympathetic to Daniel. However, Aspenaz was afraid of the king, so he said to Daniel: "The king has decided what you are to eat and drink, and if you don't look as fit as the other young men, he may kill me."
So Daniel went to the guard Melzar whom Ashpenaz had placed in charge of him and his three friends, saying:. "Test us for ten days. Give us pulse to eat and water to drink. Then compare us with the young men who are eating the food of the royal court, and base your decision of how we look."
He agreed to let them try it for ten days. At the end of ten days, they looked healthier and stronger than all those who had been eating the royal food. So from then on the guard let them continue to eat pulse and drink water.