Daniel 1:14

Then Daniel said to the steward whom the prince of the eunuchs had appointed over Daniel, Hananiah, Mishael, and Azariah:

“Test your servants, I beg you, ten days; and let them give us vegetables to eat and water to drink.

Then let our faces be examined before you, and the face of the youths who eat of the king’s delicacies; and as you see, deal with your servants.”

At the end of ten days, their faces appeared fairer and they were fatter in flesh than all the youths who ate of the king’s delicacies.

So the steward took away their delicacies and the wine that they were given to drink, and gave them vegetables.

Now as for these four youths, God gave them knowledge and skill in all learning and wisdom; and Daniel had understanding in all visions and dreams.