The angel of the Lord came back a second time and touched him and said, “Get up and eat, for the journey is too much for you.” So he got up and ate and drank. Strengthened by that food, he traveled forty days and forty nights until he reached Horeb, the mountain of God.(1 Kings 19:7-8)
And while the day was coming on, Paul besought them all to take meat, saying, This day is the fourteenth day that ye have tarried and continued fasting, having taken nothing.Wherefore I pray you to take some meat: for this is for your health: for there shall not an hair fall from the head of any of you.And when he had thus spoken, he took bread, and gave thanks to God in presence of them all: and when he had broken it, he began to eat. Then were they all of good cheer, and they also took some meat.(Acts 27:33-36)
The body also requires a range of chemicals to keep certain organs alive and to keep the correct balance in the body. These chemical are taken from the food we eat. This is why people have organ failure if they are not eating properly.