Coarse grains are good, eating healthy, etc. It is because the level of crude fiber in coarse grains is higher than that in flour and rice, and it is known that the human body cannot directly digest and absorb most of the crude fiber. But food needs to be further ground in the human body, and crude fiber can help, so there is a saying that it promotes digestion.
If you eat too much, you will easily get indigestion. Everyone who eats steamed bread knows.