'Young' in the Bible

young men without any physical defect, good-looking, suitable for instruction in all wisdom, knowledgeable, perceptive, and capable of serving in the king’s palace—and to teach them the Chaldean language and literature.

yet he said to Daniel, “My lord the king assigned your food and drink. I’m afraid of what would happen if he saw your faces looking thinner than those of the other young men your age. You would endanger my life with the king.”

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.”

At the end of 10 days they looked better and healthier than all the young men who were eating the king’s food.

God gave these four young men knowledge and understanding in every kind of literature and wisdom. Daniel also understood visions and dreams of every kind.