Q: Does The Urantia Book explain the kind of nutrition that we humans should have for a healthier body?
A: The Urantia Book states that
So, healthy habits are most important to spiritual development.
It is to the mind of perfect poise, housed in a body of clean habits, stabilized neural energies, and balanced chemical function--when the physical, mental, and spiritual powers are in triune harmony of development--that a maximum of truth can be imparted with a minimum of danger or risk. (110:6.4)
Jesus also told us that it is not that which enters the mouth that creates our spiritual challenges but what comes out of our mouths and hearts that defiles us. (153:3.5).
Nutrition is a personal matter. Each person's chemical makeup and metabolism varies to some degree. What's good for you and makes you feel happy and healthy may not be the same at all for your neighbor. The important thing in all of life is to strive for balance.
The book does say that Adam and Eve were vegitarians eating mainly fruits, nuts and grains. It also says that Jesus established the first "bloodless" Passover.